Carinatae sensu Gauthier and de Queiroz, 2001
Definition- (keeled sternum homologous with Vultur gryphus)
Ornithothoraces Chiappe and Calvo, 1994
Definition- (Iberomesornis romerali + Passer domesticus)
(Turner, Makovicky and Norell, 2012; modified from Chiappe, 1995)
Other Definitions- (Sinornis santensis + Passer domesticus)
(Sereno, online 2005; modified from Sereno, 1998)
= Ornithopectae Chiappe, 1991
Definition- (Iberomesornis romerali + Passer domesticus) (modified
from Chiappe, 1991)
= Euornithes sensu Sanz and Buscalioni, 1992
Definition- (Iberomesornis romerali + Passer domesticus) (modified)
= Ornithothoraces sensu Sereno, 1998
Definition- (Sinornis santensis + Passer domesticus) (modified)
= Ornithuromorpha sensu Chiappe, 2001
Definition- (Vorona berivotrensis + Patagopteryx deferrariisi
+ Passer domesticus) (modified)
Diagnosis- dentary teeth present (also in many non-avialans; absent
in Alethoalaornis, Gobipteryx, "Gobipipus", Archaeorhynchus,
Apsaravis and Aves); dentary not strongly forked posteriorly (also in
many non-euavialans; absent in Dapingfangornis, "Gobipipus",
Yixianornis + Songlingornis, Apsaravis and Palaeognathae);
external mandiblar fenestra absent (also in Juravenator, Compsognathidae,
Shenzhouraptor and Omnivoropterygidae; absent in Hebeiornis, Dapingfangornis,
Yixianornis and many Aves); less than thirteen dorsal vertebrae (also
in Harpymimus+Ornithomimus and Oviraptoriformes); scapulocoracoid
mobily jointed (also in Rahonavis, Shenzhouraptor and Jixiangornis;
absent in Ratites); distal end of posterodistal sternal process fused to sternum
(absent in Liaoningornithidae, Cuspirostrisornis, Hesperornis
and Ichthyornis); posterolateral sternal process extends posteriorly
past median posterior edge of sternum (also in Yandangornis; absent in
Jibeinia, Hebeiornis, Eoenantiornis and "Cathayornis"
chabuensis); projected carina on sternum (also in Parvicursorinae; absent
in Jibeinia, Longchengornis, Rapaxavis, Eoalulavis, Patagopteryx,
Hesperornis and Ratites); interclavicular angle <68 degrees (also
in Jixiangornis and Dalianraptor; absent in Hesperornis);
capital groove developed on proximal humerus (also in Gallimimus, Neimongosaurus,
Therizinosauridae, Mononykus, Deinonychus and Bambiraptor;
absent in Elsornis, Apsaravis and Ambiortus); dorsal condyle
of distal ulna developed as semilunate ridge (also in Heyuannia, Rahonavis,
Anchiornis, Zhongjianornis and Confuciusornis zhengi; absent in Eocathayornis);
less than four phalanges on manual digit III (also in Tyrannosauridae, Caudipteryx,
Jinfengopteryx and Omnivoropterygidae); alula present (also somewhat
developed in Microraptor).
References- Sanz and Buscalioni, 1992. A new bird from the Early Cretaceous of Las Hoyas,
Spain, and the early radiation of birds. Palaeontology. 35, 829-845.
Sereno, online 2005. Stem Archosauria - TaxonSearch. http://www.taxonsearch.org/dev/file_home.php
[version 1.0, 2005 November 7]
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and
paravian phylogeny. Bulletin of the American Museum of Natural History. 371,
1-206.
Aberratiodontuiformes Gong, Hou and Wang,
2004
Aberratiodontuidae Gong, Hou and Wang, 2004
Aberratiodontus Gong, Hou and Wang, 2004
A. wui Gong, Hou and Wang, 2004
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (LHV0001a/b) skull (58.7 mm), mandibles, hyoid, eleven cervical
vertebrae (88 mm), dorsal vertebrae, dorsal ribs, sacrum, caudal vertebrae?,
pygostyle (24.5 mm), scapula (53 mm), coracoid (31 mm), furcula, sternum (55
mm), sternal ribs?, humeri (69 mm), radii (70 mm), ulnae (71 mm), two carpals,
partial digit I?, partial metacarpal II, phalanx II-1, phalanx II-2, manual
ungual II, partial digit III?, ilium (46 mm), pubes (43 mm), ischium?, femur
(55 mm), tibiotarsi (66.7 mm), fibula, metatarsal I, pedal phalanx I-1 (8.7
mm), pedal ungual I, metatarsal II, phalanx II-1 (12.6 mm), phalanx II-2 (10.2
mm), pedal ungual II, metatarsal III (33 mm), phalanx III-1 (13.4 mm), rest
of digit III, metatarsal IV (31 mm), phalanx IV-1 (8.4 mm), phalanx IV-2, phalanx
IV-3, phalanx IV-4, pedal ungual IV (5.9 mm), feathers
Diagnosis- anterior four maxillary teeth much smaller than premaxillary
or posterior maxillary teeth; elongate postorbital region; about twenty-four
dentary teeth; scapula dorsoventrally curved; scapular acromion process short;
sternum elongate; broad posterolateral sternal process with weakly expanded
distal ends; manus shorter than humerus; postacetabular process broad; pubic
boot absent.
Comments- This may be an enantiornithine less derived than Protopteryx
or a euornithine outside Ornithuromorpha.
It has been suggested to be a songlingornithid (Cau and Arduini, 2008), and
a possible/probable junior synonym of Yanornis (Zhou et al., 2008/O'Connor,
2009).
References- Gong, Hou and Wang, 2004. Enantiornithine bird with diapsidian
skull and its dental development in the Early Cretaceous in Liaoning, China.
Acta Geologica Sinica. 78(1), 1-7.
Cau and Arduini, 2008. Enantiophoenix electrophyla gen. et sp. nov. (Aves,
Enantiornithes) from the Upper Cretaceous (Cenomanian) of Lebanon and its phylogenetic
relationships. Atti Societa italiana di Scienze naturali e del Museo civico
di Storia naturale in Milano. 149(II), 293-324.
Zhou, Clarke and Zhang, 2008. Insight into diversity, body size and morphological
evolution from the largest Early Cretaceous enantiornithine bird. Journal of
Anatomy. 212, 565-577.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD Thesis. University of Southern California. 586 pp.
Hollandiformes Zelenkov in Zelenkov and Kurochkin, 2015
Hollandidae Zelenkov in Zelenkov and Kurochkin, 2015
Comments- These monotypic
groups were created by Zelenkov in a book chapter by Zelenkov and
Kurochkin (2015) in Zelenkov's new parvclass Vorones that also included
monotypic orders and families for Vorona, Mystiornis and Patagopteryx.
Reference- Zelenkov and Kurochkin, 2015. Class Aves. In Kurochkin, Lopatin and
Zelenkov (eds.). Fossil vertebrates of Russia and adjacent countries.
Part 3. Fossil Reptiles and Birds. GEOS. 86-290.
Hollanda Bell, Chiappe, Erickson,
Suzuki, Watabe, Barsbold and Tsogtbaatar, 2010
= "Hollanda" Bell, Chiappe, Erickson, Suzuki, Watabe, Barsbold and
Tsogtbaatar, 2009 online
H. luceria Bell, Chiappe, Erickson, Suzuki, Watabe, Barsbold and
Tsogtbaatar, 2010
= "Hollanda luceria" Bell, Chiappe, Erickson, Suzuki, Watabe, Barsbold
and Tsogtbaatar, 2009 online
Late Campanian, Late Cretaceous
Barun Goyot Formation, Mongolia
Holotype- (MPC-b100/202) distal tibiotarsus, tarsometatarsus, proximal phalanx
II-1, phalanx III-1, phalanx III-2, proximal phalanx III-3
Paratypes- ....(MPC-b100/203) distal femur
....(MPC-b100/204) proximal tibiotarsus
....(MPC-b100/205) proximal tibiotarsus
....(MPC-b100/206) fibula
....(MPC-b100/207) fibula
Comments- The type material was discovered in 1997 and first announced
by Bell et al. (2008) as "a new taxon of primitive ornithuromorph bird."
Bell et al. (2010) later described and named the material Hollanda luceria, though their Table 1 lists it as Hollandornis birdus, clearly a typo. The authors recovered it as a
basal ornithuromorph, either intermediate between Patagopteryx and songlingornithids
or sister to Ornithurae. However, when included in a larger analysis
with a greater variety of taxa, Hollanda emerges as a non-ornithuromorph
ornithothoracine. Characters more primitive than ornithuromorphs include a lack
of distal metatarsal fusion and proximal tarsometatarsal foramina absent, while
characters shared with some enantiornithines include the posteriorly projected
laterodistal femoral margin, and metatarsal IV reduced in width.
References- Bell, Chiappe, Suzuki and Watabe, 2008. Phylogenetic and
morphometric analysis of a new ornithuromorph from the Barun Goyot Formation,
Southern Mongolia. Abstracts of the 7th International Meeting of the Society
of Avian Paleontology and Evolution.1.
Bell, Chiappe, Erickson, Suzuki, Watabe, Barsbold and Tsogtbaatar, 2010. Description
and ecologic analysis of Hollanda luceria, a Late Cretaceous bird from
the Gobi Desert (Mongolia). Cretaceous Research. 31(1), 16-26.
Kaririavis Carvalho, Agnolin, Rozadilla, Novas, Ferreira Gomes Andrade and Xavier-Neto, 2021 online
K. mater Carvalho, Agnolin, Rozadilla, Novas, Ferreira Gomes Andrade and Xavier-Neto, 2021 online
Aptian, Early Cretaceous
Pedra Branca Mine, Crato Formation, Brazil
Holotype- (UFRJ-DG 116 Av)
incomplete tarsometatarsus (mtII 17.5, mtIII 19.6, mtIV 18.3 mm),
phalanx II-1, phalanx II-2, pedal ungual II (6.6 mm), phalanx III-1,
phalanx III-2, phalanx III-3, phalanx IV-1, distal phalanx IV-2,
fragments, pedal claw sheath, ten contour feathers
Diagnosis- (after Carvalho et
al., 2022) metatarsal fusion restricted to proximal end; very shallow
proximal intercotylar eminence; proximal end of metatarsal II not
expanded and overlapped plantarly by metatarsal III; shaft of
metatarsal II thinner than metatarsal IV; hypotarsus distally extended
and forming mediolaterally thick crest that extends distally beyond
mid-length of metatarsal III; trochlea of metatarsal III with prominent
lateral condyle; distal metatarsal III with small lateral flange
defining vascular opening with metatarsal IV; distally open vascular
foramen between metatarsals III and IV; proportionally large pedal
ungual II, 1/3 of tarsometatarsal length.
Comments- The holotype was
discovered on February 25 2019 (Carvalho, pers. comm. 3-7-2022).
The description was published online on November 11 2021 but not placed
into volume 41(4) until 2022 despite volume 41(4) being catalogued as
2021.
Carvalho et al.
(2022) added this to O'Connor's bird analysis and stated it emerged in
a large ornithuromorph polytomy with Piscivoravis, Yanornis, Yixianornis, Songlingornis, Iteravis, Gansus,
hongshanornithids, Apsaravis, Ichthyornis, hesperornithines and
neognaths in a reported 15 MPTs of 1247 steps. Oddly, their
supplementary info shows "the 15 Most Parsimonious Trees (MPTs)
resulted in present phylogenetic analysis", but in all of these
Kaririavis is the sister taxon to Ichthyornis. Running the matrix
actually results in 1104 shorter trees of 1246 steps where Kaririavis
can go anywhere in Ornithothoraces except Hesperornithes+Aves and Schizoouridae sensu Wang et al.,
including trees where it is an enantiornithine. However, Carvalho et
al. claim that "35 characters [were] treated as ordered" when their
included NEXUS file leaves all characters unordered by default, and
when those characters (identified from the Mengciusornis analysis this was taken from) are ordered, 720 MPTs of 1274 steps are found where Kaririavis is the basalmost euornithine in each one. When added to Hartman et al.'s maniraptoromorph analysis, Kaririavis
can equally easily fall out as an enantiornithine or a neognath, and
with a single extra step can be sister to all other euornithines with a
plantarily displaced third metatarsal. Because of this it is
placed as Ornithothoraces incertae sedis here.
Reference- Carvalho, Agnolin,
Rozadilla, Novas, Ferreira Gomes Andrade and Xavier-Neto, 2022 (as 2021; 2021 online).
A new ornithuromorph bird from the Lower Cretaceous of South America.
Journal of Vertebrate Paleontology. 41(4), e1988623.
Lectavis Chiappe, 1993
L. bretincola Chiappe, 1993
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4021) (~575 mm) tibiotarsus (156 mm), incomplete tarsometatarsus
Diagnosis- (after Chiappe, 1993) tibiotarsus transversely wider than
deep in proximal view; distal tibiotarsal condyles strongly projected anteriorly;
slender tarsometatarsus (also in Hollanda and Neuquenornis); m.
tibialis cranialis tubercle on metatarsal II circular; proximoplantar surface
of metatarsal II forming prominent, thick edge (also in Hollanda); hypotarsus
present and mostly developed on metatarsal II.
(proposed) plantar surface of tarsometatarsus excavated (also in Confuciusornis
and Hollanda); m. tibialis cranialis tubercle on metatarsal II proximally
placed (distance from proximal edge of tubercle to proximal edge of tarsometatarsus
<60% transverse width of proximal tarsometatarsus).
Comments- Lectavis was originally identified as an enantiornithine
(Walker, 1981; Chiappe, 1991) and was labeled Type-B by Chiappe (1992) before
being named and described in 1993. It was illustrated in more detail by Chiappe
and Walker (2002). Chiappe (1992) included Lectavis in a small phylogenetic
analysis where it emerged as a non-avisaurid enantiornithine. Yet the three
characters which placed it in Enantiornithes are now known in more basal taxa
as well- plantar surface of tarsometatarsus excavated (Confuciusornis,
Patagopteryx); m. tibialis cranialis tubercle on metatarsal II (Confuciusornis,
Longicrusavis and many other euornithines); metatarsal IV reduced
in width (Zhongjianornis). Kurochkin (1996) included Lectavis
in his Alexornithiformes incertae sedis based on its enlarged medial tibiotarsal
condyle, m. tibialis cranialis tubercle on metatarsal II, and tarsometatarsal
trochlea which differ in size. Yet Kurochkin's taxonomic scheme is flawed, as
his euornithiforms Boluochia, Sinornis and Concornis have
enlarged medial condyles as well, none of his euornithiforms are known to lack
the metatarsal II tubercle, and his euornithiforms Iberomesornis, Boluochia,
Sinornis and Concornis have enlarged metatarsal II trochlea. In Hartman et al.'s (2019) maniraptoromorph analysis, it falls out sister to Hollanda within Enantiornithes, which it is likely from since all other bird remains at El Brete belong to that clade. Walker et al.
(2007) incorrectly (mistakenly) assigned the holotype to Avisaurus, while
Walker and Dyke (2009) indicate size and associations indicate it is probably
a junior synonym of Enantiornis.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe, 1991. Cretaceous birds of Latin-America. Cretaceous Research. 12, 55-63.
Chiappe, 1992. Enantiornithine (Aves) tarsometatarsi and the avian affinities
of the Late Cretaceous Avisauridae. Journal of Vertebrate Paleontology. 12(3),
344-350.
Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho
Formation of Northwestern Argentina. American Museum Novitates. 3083, 39 pp.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Hartman, Mortimer, Wahl, Lomax, Lippincott and Lovelace, 2019. A new
paravian dinosaur from the Late Jurassic of North America supports a
late acquisition of avian flight. PeerJ. 7:e7247.
Lenesornis Kurochkin, 1996
L. maltshevskyi (Nessov, 1986) Kurochkin, 1996
= Ichthyornis maltshevskyi Nessov, 1986
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 3434) (~330 mm) anterior synsacrum (~39 mm)
Comments- Kurochkin (1996) removed maltshevskyi from Ichthyornis
and placed it in a new genus, which seems correct as Lenesornis differs
in having broader anterior sacral centra which are ventrally grooved, a lower
anterior articular surface, and a fourth sacral transverse process which is
not short and dorsally directed. The latter character excludes it from Carinatae
sensu Cracraft. Kurochkin noted Lenesornis is very similar to Gobipteryx,
only differing in being less concave ventrally and having a broader anterior
articular surface (height 73% of width instead of ~82%). Gargantuavis
shares broad and low centra with a ventral groove and transverse processes which
are similar where known, but differs in that it is very decurved anteriorly,
lacks pleurocoels, has a smaller neural canal, and has a ventral keel on the
first several vertebrae. Noguerornis differs in having amphiplatyan centra,
while Iberomesornis has broader anterior sacral centra with a ventral
median prominence. Hebeiornis' sacrum is poorly preserved, but shares
the ventral groove with Gobipteryx, Pengornis, Enantiornis
and Lenesornis. The sacra of Zhyraornis and the Lecho enantiornithine
PVL-4041-4 differ in having narrower anterior sacral centra without ventral
grooves. Patagopteryx is similar in having a ventral sulcus, broad anterior
surface and slight ventral concavity, though the centra appear broader compared
to their length. Archaeorhynchus and Apsaravis also have broadly
similar sacra in relative centrum width and at least Archaeorhynchus
seems to have a ventral sulcus, though further details in either genus are unknown.
Hesperornithines and neornithines differ in having a heterocoelous anterior
articulation, while hesperornithines also differ in being non-pneumatic. Both
Gansus and Guildavis have narrower centra without a ventral sulcus.
Confuciusornis lacks a ventral sulcus anteriorly, though confuciusornithids
do share a relatively broad sacrum with concave anterior articulation with Lenesornis.
The third sacral rib is larger than in Sapeornis or Shenzhouraptor,
though sacra of those taxa are only available in dorsal view, limiting comparisons.
Non-avialans have less extensively fused sacra, especially
at such small sizes. An exception is Avimimus, which is similar in having
a lateral fossa in the first centrum and a ventral sulcus starting on the second
centrum.
In conclusion, Lenesornis is most similar to some enantiornithines and
basal euornithine, but is not an ornithurine, and is probably closer
to Passer than to Archaeopteryx. However, comparisons with non-ornithothoracine
birds are limited and the possibility Lenesornis is a very small and
highly fused non-bird maniraptoriform like Avimimus cannot be excluded.
Though it is distinguishable from other well described theropod sacra (contra
O'Connor, 2009), most are too poorly preserved or described.
References- Nessov, 1986. The first record of the Late Cretaceous bird
Ichthyornis in the Old World and some other bird bones from the Cretaceous
and Paleogene of Soviet Middle Asia. Proc. Zool. Inst. USSR Acad. Sci.. 147,
31-38.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Platanavis Nessov, 1992
P. nana Nessov, 1992
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4601) (~150 mm) mid synsacrum (~18 mm)
Diagnosis- sacral pleurocoels present in midsacral vertebrae; sacral
pleurocoels directed strongly ventrally; sacral pleurocoels very dorsoventrally
compressed; extremely deep median ventral sulcus on mid sacrum (also in Gobipteryx).
Comments- Nessov (1992) included two additional characters in his diagnosis,
but dorsoventrally compressed sacral centra are common in birds as are large
neural canals.
Mourer-Chauvire (1989) first announced the discovery of this specimen in 1989
as "part of the strange flat sacrum of a small new bird." This taxon
is based only on the mid portion of a synsacrum, containing two complete and
two partial vertebrae. It was small, as the complete vertebrae are 2.9 and 2.5
mm long each. The vertebrae are dorsoventrally compressed (~64% as tall as wide)
and elongate (1.18-1.4 times longer than maximum height). The preserved sequence
is only very slightly concave ventrally, and each centrum has a straight ventral
margin. The ventral surface features a narrow median sulcus, giving the appearance
to paired ridges. There is a low and deep pleurocoel in each complete centrum
which opens lateroventrally due to the especially broad dorsal area. The neural
canal is very wide, at least as broad as the centra.
Both Nessov (1992) and Kurochkin (2000) have assigned it to Aves incertae
sedis without comment. Indeed, the fused sacral vertebrae are too small
to derive from adult non-avialan theropods. Even tiny Caenagnathasia
and Ceratonykus would have had sacra three times larger, while Microraptor
and Jinfengopteryx were twice as large. The large neural canal, dorsoventral
compression and ventral groove are common in maniraptoriforms, including many
basal birds. Unfortunately, most Mesozoic birds have poorly preserved sacra,
and are often undescribed or only visible in dorsal view. Those of Confuciusornis
are similar in having lateral fossae and a ventral groove, but the fossae are
limited anteriorly while the groove is limited posteriorly. Zhyraornis'
sacrum is more concave ventrally, has narrower centra and lacks a groove. It
does have pleurocoels anteriorly, but these differ in being laterally directed.
The Lecho Formation enantiornithine PVL-4041-4 and Guildavis are also
more slender ventrally with no groove, and if they have pleurocoels, they are
not directed lateroventrally. Apatornis' sacrum is narrower, especially
anteriorly, and lacks pleurocoels. Gansus' sacrum is narrower and not
grooved ventrally though it does seem to have somewhat ventrally angled central
fossae on the anterior centra. Ichthyornis' sacrum has anterior centra
which are too narrow, without a ventral groove, and only the first sacral has
a slight central fossa, which is directed laterally. The posterior centra are
broader with a slight ventral groove, but lack pleurocoels. Apsaravis
has a broad sacrum, but lacks a ventral groove and pleurocoels. Gargantuavis
has a broad sacrum with a ventral keel on the posterior half, but lacks pleurocoels.
Gobipteryx's and Patagopteryx's sacra are similarly low and broad
ventrally with a median groove, but they don't seem to have pleurocoels. Lenesornis'
sacrum is similar in being broad and only slightly concave ventrally with a
ventral sulcus, but the pleurocoels are limited anteriorly and laterally directed.
The ventral grooves of Gargantuavis, Lenesornis and Patagopteryx
seem far more shallow than that of Platanavis, while Gobipteryx's
is comparably deep. Thus the closest similarity is with various ornithothoracines,
though its relationships cannot be determined further given the fragmentary
material and lack of many comparable taxa. It may end up being synonymous with
one of the Bissekty's numerous enantiornithines, such as the comparably sized
Explorornis nessovi or Incolornis silvae.
References- Mourer-Chauvire, 1989. Society of Avian Paleontology and
Evolution Information Newsletter. 3.
Nessov, 1992. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Kurochkin, 2000. Mesozoic birds of Mongolia and the former USSR. in Benton,
Shishkin, Unwin and Kurochkin, eds. The Age of Dinosaurs in Russia and Mongolia.
533-559.
"Smallornis" Zhang, 2007
"S. liaoningica" Zhang, 2007
Barremian-Albian, Early Cretaceous
Yixian, Jehol Group?, Liaoning, China
Material- skull, mandible, cervical series, coracoid, humeri,
radii, ulnae, proximal manus, ilium, pubis, incomplete femora, incomplete tibia, metatarsus,
pedal digits I-IV, body feathers, remiges
Comments- Zhang (2007) provided
this brief description (translated) - "The parietal bones are well
developed, the posterior edge of the orbit is concave, the eye holes
are large, the beak is long, and the fingers and claws are particularly
curved. The forelimbs are covered with very delicate feathers, and the
down feathers on the head are more beautifully decorated. Smallornis liaoningica is a very small arboreal bird."
The available image quality means that it can't be determined whether
this is an enantiornithine or euornithine, although the coracoid
structure shows it is ornithothoracine. None of the listed
characters are diagnostic past Pennaraptora, but I expect enough is
preserved to make it valid compared to named Jehol taxa. Until we
have a better scan of its skeleton, I'd say leave it as Ornithurothoraces
incertae sedis. It is a nomen nudum as there is no "explicit
fixation of a holotype, or syntypes" (ICZN Article 16.4.1).
Reference- Zhang, 2007. The Fossils of China. China University of Geosciences Press. 502 pp.
Wyleyia Harrison and Walker, 1973
W. valdensis Harrison and Walker, 1973
Late Berriasian-Valanginian, Early Cretaceous
Hastings Beds, England
Holotype- (NHMUK A3658) incomplete humerus (42.4 mm)
Comments- Harrison and Walker (1973) initially described Wyleyia
as a bird, noting similarities to both Archaeopteryx and Ichthyornis.
Glut (1982) notes Brett-Surman proposed this was a non-avian dinosaur
at the 1978 Society of Vertebrate Paleontology meeting, "an opinion
supported by Dr. Storrs Olson and Dr. R. T. Bakker." Harrison
(1991) referred it to Enantiornithes, while Kurochkin (1995) referred
it to Palaeognathae. Naish (2002) believed Wyleyia was a non-enantiornithine
bird, and later (2011) classified it as Maniraptora indet.. Inclusion of Wyleyia
in a TWG based matrix suggests it is most likely an ornithothoracine.
References- Harrison and Walker, 1973. Wyleyia: A new bird humerus
from the Lower Cretaceous of England. Palaeontology. 16(4), 721-728.
Glut, 1982. The New Dinosaur Dictionary. Citadel Press. 288 pp.
Norman, 1990. Problematic Theropoda: 'Coelurosauria'. In Weishampel, Dodson
and Osmolska, eds. The Dinosauria. University of California Press, Berkeley.
280–305.
Harrison, 1991. Fossil birds. In Brooke and Birkhead, eds. The Cambridge Encyclopedia
of Ornithology. Cambridge University Press, Cambridge. 69–76.
Kurochkin, 1995. Synopsis of Mesozoic birds and early evolution of Class Aves.
Archaeopteryx. 13, 47–66.
Naish, 2002. The historical taxonomy of the Lower Cretaceous theropods (Dinosauria)
Calamospondylus and Aristosuchus from the Isle of Wight. Proceedings
of the Geologists' Association. n. 113, p. 153-163.
Naish, 2011. Theropod dinosaurs. In Batten (ed.). English Wealden Fossils. The
Palaeontological Association. 526-559.
undescribed probable Ornithothoraces (MOR online)
Late Campanian, Late Cretaceous
Judith River Group, Montana, US
Material- (MOR 023) vertebra
?(MOR 1044) partial skeleton
Comments- MOR 023 was listed as "bird", while MOR 1044 was
listed as "theropod, bird?".
undescribed probable Ornithothoraces (MOR online)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, US
Material- (MOR 978) distal humerus, femur
(MOR 1086) distal humerus
(MOR 2716) distal metatarsal
(MOR 2917) distal femur
(MOR 2918) coracoid
Comments- These were listed as bird remains on MOR's online specimen
catalog, so are probably ornithothoracines based on their age.
unnamed probable ornithothoracine (Nesov, 1984)
Early Cenomanian, Late Cretaceous
Khodzhakul Formation, Uzbekistan
Material- (TsNIGRI 52/11915) dorsal vertebra (9 mm) (Nesov, 1984)
? fragments (Nessov, 1992)
Comments- Discovered in 1975, Nesov (1984) noted this specimen was amphicoelous
with a shallower lateral fossa than "Zhyraornis kashkarovi" TsNIGRI
43/11915. It is from an avebrevicaudan due to its large lateral central fossae,
probably an ornithothoracine based on its age. Nessov (1992) noted unidentified
fragments of small bird bones were found in the same locality.
References- Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
Nessov, 1992a. Mesozoic and Paleogene birds of the USSR and their
paleoenvironments. In Campbell (ed.). Papers in Avian Paleontology
Honoring Pierce Brodkorb. Natural History Museum of Los Angeles County
Science Series. 36, 465-478.
unnamed Ornithothoraces (Nesov, 1984)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (TsNIGRI 52/11915) pedal phalanx (21.3 mm) (Nesov, 1984)
(ZIN PH 9/109) posterior synsacrum (Zelenkov and Averianov, 2011)
(ZIN PO 3434c) distal humerus (Novas, 1992a)
(ZIN PO 3434f) braincase fragment, atlas, axis (Nessov, 1986)
(ZIN PO 4608) partial dentary (Nessov, 1992a,b)
(ZIN PO 4610) tooth (3.2 mm) (Nessov, 1992a,b)
(ZIN PO 4613) distal humerus (Nessov, 1992a,b)
(ZIN PO 4621) posterior mandible (Nessov, 1992a,b)
(ZIN PO 4821) partial coracoid (Nessov and Panteleev, 1993)
posterior synsacrum (Mourer-Chauvire, 1989)
Comments- TsNIGRI 52/11915 is far more elongate than any non-bird theropod, so may
belong to a euornithine or specialized enantiornithine.
Zelenkov and Averianov (2011) determined ZIN PH 9/109 was different
than Kuszholia, Zhyraornis, Platanavis, and unnamed posterior
synsacrum ZIN PO 4826. They referred it to Ornithothoraces.
Nessov (1992a) illustrated distal humerus ZIN PO 3434c he questionably
referred to Alexornithiformes. The humerus does resemble enantiornithines in
having a strongly distally projected ventral condyle, but this is seen in Apsaravis
as well, leaving the specimen referred to Ornithothoraces incertae sedis.
ZIN PO 3434f was listed as Aves indet. by Nessov (1992a),
but could conceivably derive from a small non-avian coelurosaur as well.
Nessov (1992a) noted a possibly ichthyornithiform mandible
discovered in 1989, which seems to be the partial dentary ZIN PO 4608 ascribed by him later
(1992b) to Ichthyornithiformes. The preserved portion differs from Ichthyornis
in being more slender and upcurved. It is not troodontid because it lacks a
lateral groove, and differs from that family, Dromaeosauridae and Alvarezsauridae
in having distinct alveoli. It is here placed in Ornithothoraces incertae sedis
(but is not part of Aves), as no more basal toothed avialans are
known to exist by the Turonian.
Nessov (1992a) noted teeth of small birds discovered in 1989,
one of which (ZIN PO 4610) was later illustrated by him (1992b) as possibly being ichthyornithiform.
Yet the tooth differs from Ichthyornis is being straight, more slender,
and having a basally expanded crown, and being uncompressed labiolingually.
Those features are more closely approached by Dinosaur Park Formation teeth
like RTMP 96.62.51, but it is more compressed as well. Perhaps it is an anterior
tooth. If it is indeed a bird and not a mammal or crocodilian, it seems distinct
from other well described examples.
Nessov (1992a) noted "part of a humerus of a medium-sized
bird with strange morphology (possibly a new group of Aves" discovered
in 1989. This is probably the distal humerus ZIN PO 4613 later (1992b) figured
by him as possibly enantiornithine. Indeed, the humerus resembles enantiornithines
in having a strongly distally projected ventral condyle and transversely oriented
dorsal condyle. Yet these are present in Apsaravis as well, leaving the
specimen referred to Ornithothoraces incertae sedis.
Nessov (1992a) noted a posterior bird mandible discovered in
1989, which seems to be the one later figured by him as ZIN PO 4621 (Nessov,
1992b). It seems to be ornithothoracine based on the concave dorsal surangular
edge, but further comparison is necessary to determine its precise relationships.
ZIN PO 4821 was referred to Enantiornithes by Nessov and Panteleev
(1993), then later specifically to Alexornithiformes by Panteleyev (1998). While
the deep dorsal fossa is found in enantiornithines, it is also present in Apsaravis,
limiting identication of this element to Ornithothoraces incertae sedis.
Mourer-Chauvire (1989) noted an ichthyornithiform sacrum, and
Nessov (1992) mentioned a posterior synsacrum discovered in 1989, "possibly
with affinities to ichthyornithiformes." Besides the size, said to be similar
to a recent coromorant, no further details are known. It may indeed by an ichthyornithine,
but could also be a more basal euornithine, an enantiornithine, or even a
non-bird theropod.
References- Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
Nessov, 1986. The first record of the Late Cretaceous bird
Ichthyornis in the Old World and some other bird bones from the Cretaceous
and Paleogene of Soviet Middle Asia. Proceedings of the Zoological Institute,
Leningrad. 147, 31-38.
Mourer-Chauvire, 1989. Society of Avian Paleontology and Evolution
Information Newsletter. 3.
Nessov, 1992a. Mesozoic and Paleogene birds of the USSR and their
paleoenvironments. In Campbell (ed.). Papers in Avian Paleontology
Honoring Pierce Brodkorb. Natural History Museum of Los Angeles County
Science Series. 36, 465-478.
Nessov, 1992b. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Nessov and Panteleev, 1993. On the similarity of the Late
Cretaceous ornithofauna of South America and Central Asia. Trudy Zoologicheskogo
Instituta, RAN. 252, 84-94.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Zelenkov and Averianov, 2011. Synsacrum of a primitive bird from
the Upper Cretaceous of Uzbekistan. Paleontological Journal. 45(3), 314-319.
undescribed possible Ornithothoraces (Nessov, 1992)
Early Santonian, Late Cretaceous
Yalovach Formation, Tajikistan
Material- fragments
Comments- Nessov (1992) notes rare fragments of birds are present in
this locality (spelled Jalovatsh in his paper).
Reference- Nessov, 1992. Mesozoic and Paleogene birds of the USSR and
their paleoenvironments. in Campbell (ed). Papers in Avian Paleontology Honoring
Pierce Brodkorb. Natural History Museum of Los Angeles County Science Series.
36, 465-478.
unnamed probable ornithothoracine (Malakhov and Ustinov, 1998)
Maastrichtian, Late Cretaceous
Zhuravlovskaya Svita (not Eginsaiskaya Svita), Kazakhstan
Material- (IZASK 4/KM 97) incomplete dentary (?(IZASK 4/KM 97) incomplete dentary
Comments- IZASK 4/KM 97 was referred to Asiahesperornis bazhanovi by Malakhov and Ustinov (1998), but Bell and Chiappe (2020) stated it "shows clear
alveoli for the teeth. As this is not the case among other
hesperornithiforms, and the Asiahesperornis
material consists entirely of unassociated elements, it is unlikely
this specimen belongs to a hesperornithiform bird" and reassigned it to
Aves incertae sedis. It is here provisionally placed in Ornithothoaces based on its late age.
References-
Malakhov and Ustinov, 1998. New findings of Upper Cretaceous toothed birds (Aves;
Hesperornithiformes) in northern Kazakhstan. Kazakh State University Yearbook,
Biological Series. 1998, 162-167 (in Russian).
Bell and Chiappe, 2020. Anatomy of Parahesperornis: Evolutionary mosaicism in the Cretaceous Hesperornithiformes (Aves). Life. 10(5), 62.
undescribed possible Ornithothoraces (Nessov, 1992)
Late Maastrichtian, Late Cretaceous
Kakanaut Formation, Russia
Comments- Nessov (1992) merely says there are "bones of presumably
medium-sized birds" in this locality.
Reference- Nessov, 1992. Mesozoic and Paleogene birds of the USSR and
their paleoenvironments. in Campbell (ed). Papers in Avian Paleontology Honoring
Pierce Brodkorb. Natural History Museum of Los Angeles County Science Series.
36, 465-478.
unnamed Ornithothoraces (Forster and O'Connor, 2000; described by O'Connor
and Forster, 2010)
Middle Maastrichtian, Late Cretaceous
Anembalemba Member of Maevarano Formation, Madagascar
Material- (FMNH PA 742) partial furcula
(UA 9603) partial furcula
Comments- The furculae differ from each other, so are from different
taxa.
Reference- Forster and O'Connor, 2000. The avifauna of the Upper Cretaceous
Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 20(3),
41A-42A.
O'Connor and Forster, 2010. A Late Cretaceous (Maastrichtian) avifauna from
the Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 30(4),
1178-1201.
unnamed probable Ornithothoraces (Agnolin and Martinelli, 2009)
Campanian-Maastrichtian, Late Cretaceous
Los Alamitos Formation, Rio Negro, Argentina
Material- (MACN PV RN 1103) distal pedal phalanx
(MACN PV RN 1104) distal pedal phalanx (?)II-2
(MACN PV RN 1105) pedal ungual I
(MACN PV RN 1106) manual ungual I
(MACN PV RN 1107) distal phalanx II-1
Reference- Agnolin and Martinelli, 2009. Fossil birds from the Late Cretaceous
Los Alamitos Formation, R�o Negro province, Argentina. Journal of South
American Earth Sciences. 27, 42-49.
unnamed probable ornithothoracine (Alves, Bergqvist and Brito, 2016)
Turonian-Santonian, Late Cretaceous
Adamantina Formation of the Bauru Group, Brazil
Material- (UFRJ-DG 06-Av) distal distal pedal phalanx
References- Alves, Bergqvist and Brito, 2016. New occurrences of microvertebrate
fossil accumulations in Bauru Group, Late Cretaceous of western S�o Paulo
state, Brazil. Journal of South American Earth Sciences. doi: 10.1016/j.jsames.2016.03.003
unnamed probable Ornithothoraces (Candeiro, Agnolin, Martinelli and
Buckup, 2012)
Maastrichtian, Late Cretaceous
Serra da Galga Formation of the Bauru Group, Brazil
Material- (CPP 470) pedal phalanx II-1
(CPP 481) incomplete pedal ungual
Comments- In 2021 the Serra da
Galga and Ponte Alta Members of the Marilia Formation were recognized
as the Serra da Galga Formation.
Reference- Candeiro, Agnolin, Martinelli and Buckup, 2012. First bird
remains from the Upper Cretaceous of the Peir�polis site, Minas Gerais
state, Brazil. Geodiversitas. 34(3), 617-624.
Enantiornithes Walker, 1981
Definition- (Enantiornis leali <- Passer domesticus)
(modified from Longrich, 2009)
Other definitions- (Cathayornis yandica <- Passer domesticus)
(Turner et al., 2012)
(Sinornis santensis <- Passer domesticus) (Sereno, in press;
modified from Sereno, 1998)
= Euornithiformes Kurochkin, 1996
= Enantiornithes sensu Sereno, 1998
Definition- (Sinornis santensis <- Passer domesticus) (modified)
= Enantiornithomorpha Chiappe, Ji, Ji and Norell, 1999
= Enantiornithes sensu Turner et al., 2012
Definition- (Cathayornis yandica <- Passer domesticus)
= Pengornithidae Wang et al., 2014
Definition- (Pengornis houi + Eopengornis martini) (Wang et al.,
2014)
= Voronidae Zelenkov in Zelenkov and Kurochkin, 2015
Definition- (Vorona berivotrensis <- Patagopteryx deferrariisi) (Zelenkov and Kurochkin, 2015)
Diagnosis- laterally compressed proximal coracoid (also in many Neognathae;
absent in Catenoleimus, Explorornis nessovi and Elsornis);
m. tibialis cranialis tubercle on tarsometatarsus confined to metatarsal II
(also in Velociraptor and Longicrusavis; absent in Vorona,
Rapaxavis and Yungavolucris); metatarsal II trochlea transversely
expanded (also in Falcarius, some paravians and Zhongjianornis;
absent in Alethoalaornis, Longipterygidae and Liaoningornithidae); metatarsal
IV reduced in width (also in Archaeopteryx and Zhongjianornis;
absent in Iberomesornis, Shanweiniao and Liaoningornithidae).
Comments- Wang et al. (2014) erected Pengornithidae to include Pengornis,
Eopengornis and IVPP V18632, as the most basal enantiornithines, even
moreso than Protopteryx. Yet their analysis was limited by irrationally
only including Jehol enantiornithines. Of their listed characters for Pengornithidae,
at least some are obviously primitive (numerous small teeth in upper and lower
jaws; no posteromedial sternal processes; posteromedian process broad; fibula
almost reaches proximal tarsals), and Cau (online, 2014) found that when the
non-Jehol enantiornithines were re-included Pengornithidae was no longer such
an exclusive clade.
Voronidae was named by Zelenkov in a Russian book chapter by Zelenkov
and Kurochkin (2015) as a family in his parvclass Vorones, also
including Mystiornis, Hollanda and Patagopteryx,
each given their own order and family. While no internal
phylogenetic resolution was suggested for the parvclass, a phylogenetic
definition was given for Voronidae as being (translated) "more related to Vorona berivotrensis Forster et al., 1996 than Patagopteryx deferrariisi Alvarenga et Bonaparte, 1992." In this site's topology, this covers all of Enantiornithes.
References- Chiappe, O'Connor and Zhou, 2005. Evolutionary history of
the Cretaceous Enantiornithes. Journal of Vertebrate Paleontology. 25(3), 44A.
O'Connor and Chiappe, 2008. Skull morphology of Enantiornithes (Aves: Ornithothoraces).
Journal of Vertebrate Paleontology. 28(3), 97A.
Chamero, Marugan-Lobon, Buscalioni and Sanz, 2009. The Mesozoic avian fossils
of the Iberian Peninsula. Journal of Vertebrate Paleontology. 29(3), 76A.
Dyke, Osi and Buffetaut, 2009. Large European Cretaceous enantiornithines: Morphometrics,
phylogenetics and implications for the biogeography of early birds. Journal
of Vertebrate Paleontology. 29(3), 90A.
Martin, 2009. Cyril Walker and the other half of avian evolution. Journal of
Vertebrate Paleontology. 29(3), 143A.
Cau, online 2014. http://theropoda.blogspot.com/2014/10/eopengornis-e-la-risoluzione-di.html
Wang, O'Connor, Zheng, Wang, Hu and Zhou, 2014. Insights into the evolution
of rachis dominated tail feathers from a new basal enantiornithine (Aves: Ornithothoraces).
Biological Journal of the Linnean Society. 113, 805-819.
Zelenkov and Kurochkin, 2015. Class Aves. In Kurochkin, Lopatin and
Zelenkov (eds.). Fossil vertebrates of Russia and adjacent countries.
Part 3. Fossil Reptiles and Birds. GEOS. 86-290.
Abavornis Panteleyev, 1998
A. bonaparti Panteleyev, 1998
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (TsNIGRI 56/11915) (~280 mm) coracoid shaft (~32 mm)
Diagnosis- (after Panteleyev, 1998) significant medial expansion of distal
coracoid; deep dorsal coracoid fossa (also in Neuquenornis and Enantiornis);
longitudinal groove along ventromedial edge of shaft.
(proposed) laterodistal edge angles medially.
Comments- Originally identified as Aves by Nessov and Borkin (1983) and
Nesov (1984), then as Enantiornithes by Nessov and Panteleev (1993). Elzanowski
(1995) believed the specimen was nearly identical to Gobipipus (which
he referred to juvenile Gobipteryx) and referred it to Gobipterygidae
and perhaps Gobipteryx itself. However, it differs from Gobipipus
in having the lateral edge angle distomedially, a longer shaft between the dorsal
fossa and head, the supracoracoid foramen placed completely proximal to the
dorsal fossa, and a rounded proximal edge of the dorsal fossa. In addition to
these characters, it differs from adult Gobipteryx in having a wider
shaft, deeper dorsal fossa, more distomedial expansion and a ventromedial groove.
Kurochkin (1996) referred the coracoid to Enantiornithidae indet., based on
the deep and proximally extensive dorsal fossa and convex lateral margin. The
former is also found in his alexornithid Neuquenornis however, while
the latter is found in his concornithids Concornis and Cathayornis.
Panteleyev (1998) described the specimen as the holotype of his new genus Abavornis,
which he placed in the Alexornithidae and Alexornithiformes without comment.
O'Connor (2009) declared all Bissekty enantiornithines based on coracoids to
be nomina dubia, though without detailed comparison.
References- Nessov and Borkin, 1983. [New Records of Bird Bones from
Cretaceous of Mongolia and Middle Asia]. Trudy Zoologicheskogo Instituta Akademii
Nauk SSSR. 116, 108-110.
Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
Nessov and Panteleev, 1993. On the similarity of the Late Cretaceous ornithofauna
of South America and Central Asia. Trudy Zoologicheskogo Instituta, RAN. 252,
84-94.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut Senckenberg. 181, 37-53.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
A? sp. nov. (Panteleyev, 1998)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (ZIN PO 4605) (~180 mm) coracoid shaft (~21 mm)
Comments- Originally identified as Aves by Nessov (1992), then Enantiornithes
by Nessov (1997). This is based off the distal part of a coracoid, missing the
distolateral corner. It closely resembles Avabornis bonaparti, but the
lateral edge is straight, not angled inward distally. Perhaps the edge of A.
bonaparti is broken.
References-
Nessov, 1992. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Nessov, 1997. [Cretaceous nonmarine vertebrates of northern Eurasia]. Saint
Petersburg, Institute of Earth Crust. 1-218.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Castignovolucris Buffetaut, Angst and Tong, 2023
C. sebei Buffetaut, Angst and Tong, 2023
Late Campanian, Late Cretaceous
Castigno, Gr�s � Reptiles Formation, Herault, France
Holotype- (MC-VCZ2-6) incomplete coracoid (~82 mm)
Diagnosis- (after Buffetaut et
al., 2023) coracoid head wide, with a broadly pointed acrocoracoid
process bearing a proximally-placed tubercle; very deep and narrow
groove between the triangular scapular articular facet and the
acrocoracoid process; shaft broad and relatively short, with a D-shaped
cross-section and parallel longitudinal grooves on its ventral surface;
supracoracoid foramen slit-like, lying in a medial position on the
shaft and ending distally at the level of the apex of the dorsal fossa;
dorsal fossa deeply concave; well-marked distolateral convexity; medial
wall of dorsal fossa thickened proximally.
Comments- This was first
published by Buffetaut et al. (2021), as "Enantiornithes: represented
by a large coracoid found in 2019, indicating a new taxon" and figured
as "right enantiornithe coracoid, dorsal view - Mus�e de Cruzy,
VC-Z2-6" (translated). Buffetaut et al. (2023) stated "it seems
to show similarities with some large forms from North America, such as
specimen RAM 14306 from the Campanian Kaiparowits Formation of
Utah."
References- Buffetaut, Angst,
Claude, Tong, Amoros, Boschetto, Chenet, Clavel, Maggia, Roques and
S�be, 2021. Les niveaux � vert�br�s fossiles du Cr�tac� sup�rieur de
Castigno et Combebelle (Villespassans, H�rault): historique et
nouvelles d�couvertes. Carnets natures. 8, 33-47.
Buffetaut, Angst and Tong, 2023. A new enantiornithine bird from Upper
Cretaceous non-marine deposits at Villespassans (H�rault, southern
France). Annales de Pal�ontologie. 109(1), 102585.
Catenoleimus Panteleyev,
1998
C. anachoretus Panteleyev, 1998
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4606) (~220 mm) coracoid shaft (~25 mm)
Comments- Originally identified as Enantiornithes in Nessov (1992). O'Connor
(2009) declared all Bissekty enantiornithines based on coracoids to be nomina
dubia, though without detailed comparison.
References-
Nessov, 1992b. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Cuspirostrisornithidae Hou, 1997
Cuspirostrisornis Hou,
1997
C. houi Hou, 1997
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V10897) (~140 mm, 70 g) incomplete skull (~27 mm), dentaries,
four or five cervical vertebrae, five or six dorsal vertebrae, sacrum, several
caudal vertebrae, pygostyle, partial coracoid, sternum (~23 mm), humeri (29
mm), radii (29.5 mm), ulnae (32 mm), carpometacarpus (14 mm), manual ungual,
ilium, pubis, ischium, femora (27.3 mm), tibiotarsi (32.5 mm), fibulae (~8.5
mm), tarsometatarsi (19 mm), pedal phalanges, pedal ungual I (8 mm), pedal ungual
II (8 mm), pedal ungual III (9 mm), pedal ungual IV (6 mm)
Diagnosis- distal portion of posterolateral sternal processes not fused
to sternum.
Reference- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Enantiophoenix Cau and
Arduini, 2008
E. electrophyla Cau and Arduini, 2008
Middle Cenomanian, Late Cretaceous
Ouadi al Gabour, Lebanon
Holotype- (MSNM V3882) rib fragments, synsacrum, scapula (21.3 mm), coracoids
(one partial; 19.4 mm), partial furcula, partial sternum, ilial fragment, incomplete
pubis, ischial fragments, incomplete tarsometatarsi (~28 mm), four pedal phalanges,
four pedal unguals, long bone shafts, two distal phalanges, two unguals, feathers
Comments- This specimen was briefly described as an enantiornithine but
unnamed by Dalla Vecchia and Chiappe (2002), then described in detail and named
by Cau and Arduini (2008). Cau and Arduini assigned Enantiophoenix to
the Avisauridae based on their phylogenetic analysis.
References- Dalla Vecchia and Chiappe, 2002. First avian skeleton from
the Mesozoic of Northern Gondwana. Journal of Vertebrate Paleontology. 22(4),
856-860.
Cau and Arduini, 2008. Enantiophoenix electrophyla gen. et sp. nov. (Aves,
Enantiornithes) from the Upper Cretaceous (Cenomanian) of Lebanon and its phylogenetic
relationships. Atti Soc. it. Sci. nat. Museo civ. Stor. nat. Milano. 149(II),
293-324.
"Enantiornis" walkeri
Nessov and Panteleev, 1993
= Explorornis walkeri (Nessov and Panteleev, 1993) Panteleyev, 1998
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4825) (~300 mm) proximal coracoid (~35 mm)
Diagnosis- (proposed) acrocoracoid process dorsoventrally deep (>50%
as deep at level of junction between scapular facet and acrocoracoid as the
coracoid head is long); coracoid lateral convexity begins on shaft proximal
to dorsal fossa.
Other diagnoses- Nessov and Panteleev (1993) distinguished walkeri
from Enantiornis leali based on several characters. The coracoid process
is not narrower however. The acrocoracoid process is not actually shorter than
in Enantiornis, but appears so due to its depth. The proximal shaft is
transversely wider, but this is plesiomorphic. The elongate supracoracoid foramen
seems to be the medial exit, which is also elongate in Enantiornis.
Kurochkin (2000) listed two features in his diagnosis to separate walkeri
from leali. The coracoid process is even more stout in Explorornis,
and equally so in Incolornis, Neuquenornis and Catenoleimus.
The proximal shaft is more gracile dorsoventrally, but this is also true of
Gurilynia, Gobipteryx and Explorornis.
Comments- This specimen was discovered in 1991 and named "Enantiornis"
walkeri by Nessov and Panteleev (1993). While the quotation marks suggest
they did not believe the species to actually be Enantiornis, they did
place it within the Enantiornithiformes. Kurochkin (1996) removed the quotation
marks, as he believed it was referrable to Enantiornis based on the obtuse
acrocoracoid tip, stout coracoid process and proximally (dorsoventrally?) thick
shaft. However, the acrocoracoid tip is no more obtuse than Explorornis,
Incolornis martini and Alexornis, the coracoid process is less
stout in Enantiornis than in Explorornis, Incolornis, Catenoleimus,
Otogornis or Neuquenornis, and the shaft isn't thick as in Enantiornis
and is much thinner than in Incolornis. Kurochkin (2000) later kept the
species in Enantiornis and added a couple coracoid features to his diagnosis
of the genus- short coracoid shaft; stout acrocoracoid process. The former is
plesiomorphic, while the latter is also present in Otogornis and Incolornis.
Panteleyev (1998) transferred walkeri to his new genus Explorornis
(within Alexornithidae and Alexornithiformes) without justification, though
it does share that genus' primitive dorsoventrally compressed coracoid shaft
and shallow dorsal fossa. Yet it lacks the apomorphic dorsolateral ridge of
Explorornis. walkeri does not seem to be definitively referrable
to either genus. O'Connor (2009) declared all Bissekty enantiornithines based
on coracoids to be nomina dubia, though without detailed comparison.
References- Nessov and Panteleev, 1993. On the similarity of the Late
Cretaceous ornithofauna of South America and Central Asia. Trudy Zoologicheskogo
Instituta, RAN. 252, 84-94.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Kurochkin, 2000. Mesozoic birds of Mongolia and the former USSR. in Benton,
Shishkin, Unwin and Kurochkin, eds. The Age of Dinosaurs in Russia and Mongolia.
533-559.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
E? sp. (Panteleyev, 1998)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (ZIN PO 4817) proximal coracoid (~28 mm)
Comments- This coracoid is not figured, but Panteleev says it resembles
walkeri more than E. nessovi or the other Explorornis species.
Its true relationships remain unknown.
Reference- Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Evgenavis O'Connor, Averianov
and Zelenkov, 2014
E. nobilis O'Connor, Averianov and Zelenkov, 2014
Barremian, Early Cretaceous
Ilek Formation, Russia
Holotype- (ZIN PH 1/154) incomplete tarsometatarsus (48.68 mm)
Diagnosis- (after O'Connor et al., 2014) metatarsals fused only proximally;
tarsometatarsus plantarly excavated; metatarsal II trochlea wide and angled
so that lateral condyle extends farther than medial condyle; medial condyle
of metatarsal II trochlea strongly projected plantarily; dorsal and plantar
depressions of metatarsal II trochlea well developed; tubercle on proximal dorsal
surface of metatarsal III, with another just distal to it on metatarsal II;
plantar surface of metatarsal III strongly medially excavated proximal to trochlea;
distal vascular foramen closed by medial projection of metatarsal IV; metatarsal
IV with small, non-perforating, plantar foramina; metatarsal IV trochlea non-ginglymous;
metatarsal V present.
Comments- The holotype was discovered in 2007. Despite stating "Evgenavis
differs from Confuciusornis only in size and proportions, being larger
and more slender and waisted than the latter", O'Connor et al. recovered
it as an enantiornithine in their analysis (based on O'Connor's matrix). They
ended up merely placing it in Aves incertae sedis. The fact that the four taxa
this paper added to O'Connor's matrix ended up in a clade together when implied
weights were used could suggest systematic coding errors/differences compared
to O'Connor's original taxa. As Cau (online, 2014) recovered Evgenavis
as an enantiornithine as well, it is tentatively placed in that clade here.
References- Cau, online 2014. http://theropoda.blogspot.com/2014/05/evgenavis-fortunguavis-tianyuornis.html
O'Connor, Averianov and Zelenkov, 2014. A confuciusornithiform (Aves, Pygostylia)-like
tarsometatarsus from the Early Cretaceous of Siberia and a discussion of the
evolution of avian hind limb musculature. Journal of Vertebrate Paleontology.
34(3), 647-656.
Feitianius O'Connor, Li, Lamanna,
Wang, Harris, Atterholt and You, 2015
F. paradisi O'Connor, Li, Lamanna, Wang, Harris, Atterholt and
You, 2015
Late Aptian, Early Cretaceous
Xiagou Formation, Gansu, China
Holotype- (CAGS-IG-05-CM-004) (male?) last five dorsal vertebrae, two dorsal
ribs, dorsal rib fragments, gastralia, synsacrum, five or six caudal vertebrae,
pygostyle, chevrons, partial ilium, incomplete pubes (23.4 mm), ischia (13.7
mm), femora (27.1 mm), tibiotarsi (35.7 mm), fibulae, metatarsals I (4.7 mm),
phalanges I-1 (5.1 mm), pedal unguals I (~5.5 mm), tarsometatarsi (22.7 mm;
II ~20.5, III 22.7, IV 21.3 mm), phalanges II-1 (4.5 mm), phalanges II-2 (6.2
mm), pedal unguals II (~5 mm), phalanges III-1 (6.3 mm), phalanges III-2 (5.5
mm), phalanges III-3 (6.2 mm), pedal unguals III (~6 mm), phalanges IV-1 (3.2
mm), phalanges IV-2 (2.8 mm), phalanges IV-3 (3.1 mm), phalanges IV-4 (4.7 mm),
pedal unguals IV (~5.5 mm), pedal claw sheaths, collagen, uropygium, body feathers,
retrices
Diagnosis- (after O'Connor et al., 2015) shallow lateral dorsal fossae;
very small cuppedicus fossa; robust, curved, weakly retroverted pubis; dorsally
tapered pubic boot; ischium weakly sigmoid; ischium with delicate ridge on anterior
half of lateral surface; medial plantar crest well developed on tarsometatarsus;
lateral plantar crest minimally developed; penultimate pedal phalanges the longest
in each digit; pedal phalanges II-1 and II-2 dorsoventrally compressed and mediolaterally
wide; pedal unguals large and relatively weakly recurved; pedal unguals with
long sheaths; several different rectricial morphotypes.
Comments- This specimen was discovered in 2005 and first noted in Lamanna
et al. (2009) and O'Connor (2009). O'Connor et al. (2015) named and described
it as an enantiornithine in a basal polytomy (possibly caused by the inclusion
of other partial specimens).
References- Lamanna, Li, Harris, Atterholt and You, 2009. Exceptionally
preserved Enantiornithes (Aves: Ornithothoraces) from the Early Cretaceous of
Northwestern China. Journal of Vertebrate Paleontology. 29(3), 131A.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
O'Connor, Li, Lamanna, Wang, Harris, Atterholt and You, 2015. A new Early Cretaceous
enantiornithine (Aves, Ornithothoraces) from northwestern China with elaborate
tail ornamentation. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2015.1054035
Gracilornis Li and Hou,
2011
G. jiufotangensis Li and Hou, 2011
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (PMOL-AB00170) skull (~34.1 mm), mandibles, eleven cervical
vertebrae, three dorsal vertebrae, dorsal ribs, eight sacral vertebrae, six
caudal vertebrae, pygostyle (12.8 mm), scapulae, coracoids (14.5 mm), furcula
(15.5 mm), sternum (14.6 mm), humeri (24.4 mm), radii (24.3 mm), ulnae (26.3
mm), pisiform, metacarpals I (1.9 mm), phalanges I-1 (~4.1 mm), manual ungual
I (~.7 mm), carpometacarpus (II 10.4, III 12.5 mm), phalanges II-1 (6.9 mm),
phalanges II-2 (4.1 mm), manual ungual II (1.5 mm), phalanges III-1 (3.4 mm),
ilia, pubes (19.4 mm), ischium, femora (21.1 mm), tibiotarsi (27.2 mm), fibula
(6.5 mm), metatarsals I (3.1 mm), phalanges I-1 (3.9 mm), pedal unguals I (4.3
mm), tarsometatarsi (III 14.2, III 15.1, IV 14.1 mm), phalanges II-1 (3.5 mm),
phalanges II-2 (4.7 mm), pedal unguals II (4.6 mm), phalanges III-1 (4.6 mm),
phalanges III-2 (4.1 mm), phalanges III-3 (4.1 mm), pedal ungual III (4.2 mm),
phalanx IV-1 (2.4 mm), phalanx IV-2 (2.1 mm), phalanx IV-3 (2.1 mm), pedal ungual
IV (3.9 mm)
Diagnosis- (after Li and Hou, 2011) slender skeleton; small sternum (sternum
length/trunk length ~0.11, sternum width/trunk length ~0.13); well developed
arthroses of limbs.
Comments- The diagnosis is vague except for sternum size, which increases
in ontogeny.
Reference- Li and Hou, 2011. Discovery of a new bird (Enantiornithines)
from Lower Cretaceous in Western Liaoning, China. Journal of Jilin University
(Earth Science Edition). 41(3), 759-763.
Huoshanornis Wang, Zhang, Gao,
Hou, Meng and Liu, 2010
H. huji Wang, Zhang, Gao, Hou, Meng and Liu, 2010
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (D2126) skull, mandible, seven cervical vertebrae, three dorsal
vertebrae, dorsal ribs, synsacrum, four caudal vertebrae, pygostyle (9.4 mm),
scapula, coracoids (14.1 mm), incomplete furcula, incomplete sternum, humeri
(21.3 mm), radii, ulnae (24.5 mm), pisiform, phalanges I-1 (3.9 mm), manual unguals
I, metacarpals II (13.9 mm), phalanges II-1, phalanges II-2, manual unguals
II, metacarpals III, phalanges III-1, pubes, ischium, femora (20.8 mm), tibiotarsi
(27.5 mm), metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi (15.5
mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges
III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges
IV-3, phalanges IV-4, pedal unguals IV
Diagnosis- (after Wang et al., 2010) intermetacarpal space broad; phalanx
I-1 greatly reduced, roughly one fourth the length of the carpometacarpus; phalanx
III-1 as long as and almost as wide as II-1; posterolateral sternal process
slightly shorter than posteromedian process, with remarkable triangular expansion
at its distal end.
Comments- This specimen was discovered before 2010 and was originally
described in an elusive thesis by an unknown author.
References- Wang, Zhang, Gao, Hou, Meng and Liu, 2010. A new enantiornithine
bird from the Early Cretaceous of Western Liaoning, China. The Condor. 112(3),
432-437.
?, 20??. Description of a new enantiornithine bird from the Early Cretaceous
of western Liaoning, China. Masters Thesis. 66 pp.
Iberomesornithiformes Sanz and Bonaparte, 1992
Definition- (Iberomesornis romeralii < Cathayornis yandica,
Gobipteryx minuta, Enantiornis leali) (Martyniuk, 2012)
Iberomesornithidae Sanz and Bonaparte, 1992
References- Sanz and Bonaparte, 1992. A new order of birds (Class Aves) from the
Lower Cretaceous of Spain. In Campbell (ed.). Papers in Avian
Paleontology Honoring Pierce Brodkorb. Proceedings of the II
International Symposium of the Society of Avian Paleontology and
Evolution. 38-49.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Iberomesornis Sanz
and Bonaparte, 1992
I. romerali Sanz and Bonaparte, 1992
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Holotype- (LH-22) (87 mm) fragment of sixth cervical vertebra, seventh cervical
vertebra (2.3 mm), eighth cervical vertebra (2.2 mm), ninth cervical vertebra
(1.9 mm), tenth cervical vertebra (1.8 mm), first dorsal vertebra (1.7 mm),
second dorsal vertebra (1.7 mm), third dorsal vertebra (1.7 mm), fourth dorsal
vertebra (1.7 mm), fifth dorsal vertebra (1.7 mm), sixth dorsal vertebra (1.7
mm), seventh dorsal vertebra (1.7 mm), eighth dorsal vertebra (1.8 mm), ninth
dorsal vertebra (1.8 mm), tenth dorsal vertebra (1.7 mm), eleventh dorsal vertebra
(1.7 mm), thirteen dorsal ribs, dorsal rib fragments, first sacral vertebra
(1.4 mm), second sacral vertebra (1.4 mm), third sacral vertebra, fourth sacral
vertebra (~1.3 mm), fifth sacral vertebra (~1.3 mm), sixth sacral vertebra (1.2
mm), seventh sacral vertebra (1 mm), eighth sacral vertebra (.9 mm), first caudal
vertebra (.9 mm), second caudal vertebra (.9 mm), third caudal vertebra (.9
mm), fourth caudal vertebra (.9 mm), fifth caudal vertebra (.9 mm), sixth caudal
vertebra (.8 mm), six chevrons, pygostyle (9.2 mm), partial scapula (10.1 mm),
coracoids (9.9 mm), furcula, partial sternum, eight sternal ribs, incomplete
humerus (~17.6 mm), radius (18.2 mm), incomplete ulna (~19.2 mm), partial ilia
(10.3 mm), partial pubes, ischia, incomplete femora (16.4 mm), tibiotarsi (20
mm), metatarsal I (2.4 mm), phalanx I-1 (2.9 mm), pedal ungual I (2.5 mm), metatarsal
II (11.2 mm), phalanx II-1 (2.3 mm), phalanx II-2 (3.5 mm), pedal ungual II
(2.2 mm), metatarsal III (11.8 mm), phalanx III-1 (3.2 mm), phalanx III-2 (2.8
mm), phalanx III-3 (3.4 mm), pedal ungual III (2.3 mm), metatarsal IV (11.5
mm), phalanx IV-1 (1.9 mm), phalanx IV-2 (1.6 mm), phalanx IV-3 (1.7 mm), phalanx
IV-4 (2.4 mm), pedal ungual IV (1.8 mm)
Referred- ?(LH-8200) metatarsal I, pedal phalanx I-1, pedal ungual I,
tarsometatarsus (14 mm), pedal phalanx II-1, pedal phalanx II-2, pedal ungual
II, pedal phalanx III-1, pedal phalanx III-2, pedal phalanx III-3, pedal ungual
III, pedal phalanx IV-1, pedal phalanx IV-2, pedal phalanx IV-3, pedal phalanx
IV-4, pedal ungual IV (Sanz and Buscalioni, 1994)
Diagnosis- pubic peduncle of ilium directed anteroventrally.
References- Sanz, Bonaparte and Lacasa, 1988. Unusual Early Cretaceous birds from Spain. Nature. 331, 433-435.
Sanz and Bonaparte, 1992. A new order of birds (Class Aves) from the
Lower Cretaceous of Spain. In Campbell (ed.). Papers in Avian
Paleontology Honoring Pierce Brodkorb. Proceedings of the II
International Symposium of the Society of Avian Paleontology and
Evolution. 38-49.
Sanz and Buscalioni, 1994. An isolated bird foot from the Barremian (Lower Cretaceous)
of Las Hoyas (Cuenca, Spain). G�obios, M�moire Sp�ciale.
16, 213-217.
Sereno, 2000. Iberomesornis romerali (Ornithothoraces, Aves) re-evaluated
as an enantiornithine bird. Neues Jahrbuch f�r Geologie und Pal�ontologie
Abhandlungen. 215, 365-395.
Sanz, P�rez-Moreno, Chiappe and Buscalioni, 2002. The birds from the
Lower Cretaceous of Las Hoyas (Privince of Cuenca, Spain). pp 209-229. In Chiappe
and Witmer (eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
"Ichthyornis" minusculus
Nessov, 1990
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistanan
Holotype- (ZIN PO 3941) (~205 mm) dorsal vertebra (4 mm)
Comments- Mourer-Chauvire (1989) mentioned this as a "vertebra of
an Ichthyornithiform the size of a thrush." This specimen can be assigned
to Enantiornithes based on its centrally located parapophysis.
References- Mourer-Chauvire, 1989. Society of Avian Paleontology and
Evolution Information Newsletter. 3.
Nessov, 1990. Small ichthyornithiform bird and other bird remains from Bissekty
Formation (Upper Cretaceous) of central Kyzylkum Desert. Proceedings of the
Zoological Institute, Leningrad. 210, 59-62 (in Russian).
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Incolornis Panteleyev, 1998
Diagnosis- (proposed) very deep coracoid shaft (>40% of proximodistal
head length); proximodorsal bump located on shaft just distal to scapular facet.
Other diagnoses- Panteleyev (1998) listed three diagnostic characters
for Incolornis. Of these, the ventral longitudinal ridge on the coracoid
shaft is also present in Iberomesornis, Enantiornis and Gobipteryx.
The narrow coracoid tubercle is found in a wide range of taxa (e.g. Catenoleimus,
Elsornis, Gurilynia, Enantiornis, Eocathayornis,
Cathayornis). Finally, the supracoracoid foramen has its proximal exit
on the middle of the medial side of the shaft in Enantiornis, Otogornis
and Neuquenornis as well. O'Connor (2009) declared all Bissekty enantiornithines
based on coracoids to be nomina dubia, though without detailed comparison.
Reference- Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
I. silvae Panteleyev, 1998
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4604) (~135 mm) proximal coracoid (~15 mm)
Diagnosis- (after Panteleyev, 1998) smaller than I. martini.
(proposed) proximodorsal coracoid bump placed further distally than in I.
martini.
Comments- This was discovered in 1989 and originally identified as Enantiornithes(?)
by Nessov and Panteleev (1993) and Nessov (1997). Panteleyev (1998) made it the
type species of his new genus Incolornis. While O'Connor (2009) stated
the proximodorsal bump was similar to Protopteryx, the latter's process
is medial instead of dorsal so topologically congruent with the procoracoid
process.
References- Nessov and Panteleev, 1993. On the similarity of the Late
Cretaceous ornithofauna of South America and Central Asia. Trudy Zoologicheskogo
Instituta, RAN. 252, 84-94.
Nessov, 1997. [Cretaceous nonmarine vertebrates of northern Eurasia]. Saint
Petersburg, Institute of Earth Crust. 1-218.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
I. martini (Nessov and Panteleev,
1993) Panteleyev, 1998
= Enantiornis martini Nessov and Panteleyev, 1993
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4609) (~220 mm) proximal coracoid (~25 mm)
Diagnosis- (after Panteleyev, 1998) larger than I. silvae.
(proposed) proximodorsal coracoid bump placed further proximally than in I.
silvae.
Other diagnoses- Kurochkin (1996) listed the narrow coracoid tubercle
as a diagnostic feature, but as noted in the genus diagnosis, this is widespread
in enantiornithines. He also listed the stout shaft, which is covered in the
genus diagnosis above.
Panteleyev (1998) also distinguishes I. martini from I. silvae
based on the supposedly less transversely flattened coracoid shaft, but this
seems untrue as I. martini has a width/depth ratio of 69% while I.
silvae's is 74%. His final character is the larger groove between the glenoid
and acrocoracoid in I. martini, but this could be due to erosion in I.
silvae's holotype.
Comments- This was discovered in 1989 and originally figured as a scapula
of Enantiornithidae indet. by Nessov (1992). It was later described as "Enantiornis"
martini by Nessov and Panteleev (1993), which may indicate they did not
feel it belonged in that genus. Kurochkin (1996) believed it was Enantiornis
based on the obtuse acrocoracoid tip and stout coracoid process. However, the
acrocoracoid tip is no more obtuse than Explorornis, walkeri,
and Alexornis, and the coracoid process is less stout in Enantiornis
than in Explorornis, Catenoleimus, Otogornis or Neuquenornis.
Kurochkin (2000) later kept the species in Enantiornis and added a couple
coracoid features to his diagnosis of the genus- short coracoid shaft; stout
acrocoracoid process. The former is plesiomorphic, while the latter is also
present in Otogornis and walkeri. Panteleev (1998) referred this
species to his new genus Incolornis, based on I. silvae, which
seems correct despite his listed diagnosis for the genus being problematic.
References-
Nessov, 1992. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Nessov and Panteleev, 1993. On the similarity of the Late Cretaceous ornithofauna
of South America and Central Asia. Trudy Zoologicheskogo Instituta, RAN. 252,
84-94.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Kurochkin, 2000. Mesozoic birds of Mongolia and the former USSR. in Benton,
Shishkin, Unwin and Kurochkin, eds. The Age of Dinosaurs in Russia and Mongolia.
533-559.
"Jinzhouornis" "delicates" Zhang, 2007
Barremian-Aptian, Early Cretaceous
Yixian, Yixian Formation, Liaoning, China
Material- (juvenile) incomplete
skull, cervical series, dorsal series, dorsal ribs, sacrum, caudal
series, pygostyle, scapulae, coracoids, sternum(?), humeri, radii,
ulnae, manus (one partial), ilia, femora, tibiae, metatarsus, pedal
digits I-IV, body feathers, remiges
Comments- Zhang (2007) provided this brief description (translated) - "The primitive bird whose individual is smaller than the petite Liaoxiornis,
belongs to the Enantiornithes group. The head is short and round, the
skull is relatively developed, and the jaw has teeth. The outer body is
feathered, and the forelimbs have become wings. There are 3 curved
finger claws, which are relatively developed, the sternal keel is
prominent, the caudal vertebra have fused, and the tail is short. ...
This fossil is the smallest bird fossil discovered in the Late
Jurassic-Early Cretaceous Yixian Formation of western Liaoning, China,
and it remains to be studied."
The generic assignment is odd because Jinzhouornis
is a confuciusornithid, but this is stated to be an
enantiornithine. That identification seems to be correct, given
the short fused premaxillae preserved left of the main skull, coracoid
and humeral shape, tiny diamond-shaped sternum, and manus with short
digit I and reduced ungual and seemingly long metacarpal III projecting
past II. In addition to the sternal anatomy, the poorly ossified
ends of elements and stated small size strongly suggests a young
age. The description seems inaccurate in that the round head is
probably due to beak elements overlapping the posterior cranium, the
manual unguals are not well developed or necessarily three in number,
and the sternum shows no sign of a keel. The other details are
congruent with a juvenile enantiornithine, and this specimen is likely
indeterminate as are most other juvenile enantiornithines ( e.g. Liaoxiornis, Dalingheornis,
GMV-2158 and 2159). It is a nomen nudum as there is no "explicit
fixation of a holotype, or syntypes" (ICZN Article 16.4.1).
Reference- Zhang, 2007. The Fossils of China. China University of Geosciences Press. 502 pp.
Longchengornis Hou, 1997
L. sanyanensis Hou, 1997
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V10530) (~110 mm, 86 g) frontals, parietals, axis (3
mm), postaxial cervical vertebrae, dorsal vertebrae, dorsal ribs, sacrum (14
mm), fifteen caudal vertebrae, scapula, coracoids (17 mm), furcula, sternum,
humeri (32.5 mm), radius (29 mm), ulna, scapholunare, pisiform, metacarpal I, phalanx
I-1, manual ungual I, carpometacarpus (15 mm), manual phalanx II-1, partial
ilium (17 mm), pubis (~21 mm), ischium (~11 mm), femur (21.5 mm), tibiotarsi
(~34 mm), fibula, pedal phalanx I-1 (5.5 mm), pedal ungual I (7 mm), tarsometatarsus
(~21.5 mm), pedal phalanx II-1, pedal phalanx II-2, pedal ungual II (8 mm),
pedal phalanx III-1, pedal phalanx III-2, pedal phalanx III-3, pedal ungual
III, pedal phalanx IV-1, pedal phalanx IV-2, pedal phalanx IV-3, pedal phalanx
IV-4, pedal ungual IV
Diagnosis- large foramen in proximal humerus.
Comments- Pittman et al. (2020) listed Longchengornis as a junior synonym of Cathayornis without comment.
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Pittman, O'Connor, Tse, Makovicky, Field, Ma, Turner, Norell, Pei and
Xu, 2020. The fossil record of Mesozoic and Paleocene pennaraptorans.
In Pittman and Xu (eds.). Pennaraptoran Theropod Dinosaurs: Past
Progress and New Frontiers. Bulletin of the American Museum of Natural
History. 440(1), 37-95.
Yuanjiawaornis Hu, Liu,
Li, Xu and Hou, 2015
Y. viriosus Hu, Liu, Li, Xu and Hou, 2015
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (PMOL AB00032) (subadult) seven dorsal vertebrae, dorsal ribs,
gastralia, synsacrum, six caudal vertebrae, chevrons, pygostyle (22.5 mm), scapulae
(one incomplete), coracoids (28 mm), furcula, sternum (34 mm), sternal ribs,
humeri (51 mm), radii (49 mm), ulnae (53 mm), scapholunare, pisiform, proximal carpal
fragments, metacarpal I (5.5 mm), phalanx I-1 (11 mm), manual unguals I (4.5
mm), metacarpal II (~21.5 mm), phalanx II-2, metacarpals III (one incomplete;
22.5 mm), phalanx III-1, ilia (29 mm), pubes (36 mm), ischia, incomplete femora
(43 mm), tibiotarsi (50.5 mm), fibulae (20.5 mm), metatarsal I (6.5 mm), phalanx
I-1 (7 mm), pedal unguals I (9 mm), tarsometatarsi (mtII 24.5, mtIII 27, mtIV
25 mm), pedal phalanx, pedal ungual II/III/IV (9 mm)
Diagnosis- (after Hu et al., 2015) large size (but smaller than Pengornis);
ventral surface of synsacrum grooved longitudinally (ridged in Bohaiornis
and Parabohaiornis); transverse processes of last sacral vertebra robust
and long (those of penultimate sacral vertebra robust and long in Zhouornis,
Parabohaiornis and Longusunguis); acromion process tapered anterodorsally
(nearly parallel to scapular shaft in bohaiornithids except Longusunguis);
lateral margin of coracoid straight (strongly convex in Pengornis, Shenqiornis,
Sulcavis and Longusunguis); clavicular rami medially curved and
omal tips tapered (clavicular rami straight and omal tips expanded laterally
in bohaiornithids); sternum oval in outline with posterolateral processes slightly
expanded distally (processes strongly expanded distally in most bohaiornithids,
and anterolateral margin of sternum angular in Zhouornis); forelimb and
hind limb subequal in length (forelimb much longer than hind limb in Pengornis);
humeral head flat (convex in Pengornis and concave in bohaiornithids
except Zhouornis); deltopectoral crest gradually decreases in height
distally (abruptly decreases distally in Shenqiornis, Sulcavis
and Longusunguis).
Comments- The holotype was discovered in 2005. It was assigned to Enantiornithes
and said to resemble bohaiornithids, but was not included in a phylogenetic
analysis.
Reference- Hu, Liu, Li, Xu and Hou, 2015. Yuanjiawaornis viriosus,
gen. et sp. nov., a large enantiornithine bird from the Lower Cretaceous of
western Liaoning, China. Cretaceous Research. 55, 210-219.
unnamed Enantiornithes (Morrison, Dyke and Chiappe, 2005)
Late Campanian, Late Cretaceous
Northumberland Formation of the Nanaimo Group, British Columbia, Canada
Material- (RBCM.EH2005.003.0002.A) incomplete radius (106 mm) (Morrison,
Dyke and Chiappe, 2005)
(RBCM.EH2005.003.0002.B) proximal coracoid (Morrison, Dyke and Chiappe, 2005)
(RBCM.EH2009.021.0001) incomplete femur (70 mm), proximal tibiotarsus, partial
fibula (Dyke, Wang and Kaiser, 2011)
References- Morrison, Dyke and Chiappe, 2005. Cretaceous fossil birds
from Hornby Island (British Columbia). Canadian Journal of Earth Sciences. 42,
2097-2101.
Dyke, Wang and Kaiser, 2011. Large fossil birds from a Late Cretaceous marine
turbidite sequence on Hornby Island (British Columbia). Canadian Journal of
Earth Sciences. 48, 1489-1496.
unnamed enantiornithine (Currie and Padian, 1983)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material- (RTMP 79.14.247) distal tibiotarsus (11 mm wide)
Comments- This was originally identified as a pterosaur tibiotarsus by
Currie and Padian (1983).
References- Currie and Padian, 1983. A new pterosaur record from the
Judith River (Oldman) Formation of Alberta. Journal of Paleontology, 57(3),
599-600,
Buffetaut, 2010. A basal bird from the Campanian (Late Cretaceous) of Dinosaur
Provincial Park (Alberta Canada). Geological Magazine. 147(3), 469-472.
unnamed possible Enantiornithes (Cumbaa and Tokaryk, 1993)
Middle Cenomanian, Late Cretaceous
Carrot River, Belle Fourche Member of the Ashville Formation, Saskatchewan, Canada
Material- (RSM P2077.66) distal metatarsal III (Tokaryk, Cumbaa and Storer, 1997)
Middle Cenomanian, Late Cretaceous
Bainbridge River, Belle Fourche Member of the Ashville Formation, Saskatchewan, Canada
(RSM P2989.26) proximal scapula (Sanchez, 2010)
Comments- Cumbaa and Tokaryk (1993) referred to a "presumed
enantiornithine" at the Carrot River site. It was later described by Tokaryk et al. (1997) as a
possible enantiornithine based on the lack of distal fusion. However, this is
a primitive character, so it should be compared to other theropod metatarsi.
Sanchez (2010) lists RSM P2989.26 as "Enantiornithes?".
References- Cumbaa and Tokaryk, 1993. Early birds, crocodile tears, and
fish tales: Cenomanian and Turonian marine vertebrates from Saskatchewan, Canada.
Journal of Vertebrate Paleontology. 13(3), 31A-32A.
Tokaryk, Cumbaa and Storer, 1997. Early Late Cretaceous birds from Saskatchewan,
Canada: The oldest diverse avifauna known from North America. Journal of Vertebrate
Paleontology. 17(1), 172-176.
Sanchez, 2010. Late Cretaceous (Cenomanian) Hesperornithiformes from
the Pasquia Hills, Saskatchewan, Canada. Masters thesis, Carleton
University. 238 pp.
unnamed enantiornithine (Longrich, Tokaryk and Field, 2011)
Late Maastrichtian, Late Cretaceous
Frenchman Formation, Saskatchewan, Canada
Material- (NMC 9528; Lancian Enantiornithine A) proximal coracoid
Reference-
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the
Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National
Academy of Sciences of the United States of America. 108(37),
15253-15257.
unnamed enantiornithine (Longrich, Tokaryk and Field, 2011)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, US
Material- (YPM 57823; Lancian Enantiornithine B) proximal coracoid
Comments- This differs from YPM 57235, which Longrich et al. (2011) refer to Avisaurus archibaldi due to its large size.
Reference-
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the
Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National
Academy of Sciences of the United States of America. 108(37),
15253-15257.
unnamed enantiornithine (Hutchison, 1993)
Late Campanian, Late Cretaceous
Kaiparowitz Formation, Utah, US
Material- (RAM 14306) proximal coracoid (Farke and Patel, 2012)
Comments- Atterholt et al. (2018) found this differs from the contemporaneous Mirarce in having an angular acrocoracoid, and deeper groove between the scapular cotyla and glenoid.
Reference-
Farke and Patel, 2012. An enantiornithine bird from the Campanian Kaiparowits
Formation of Utah, USA. Cretaceous Research. 37, 227-230.
Atterholt, Hutchison and O'Connor, 2018. The most complete
enantiornithine from North America and a phylogenetic analysis of the
Avisauridae. PeerJ. 6:e5910.
undescribed enantiornithine (Galton, Dyke and Kurochkin, 2009)
Berriasian, Early Cretaceous
Purbeck Limestone Group, England
Material- humerus
Reference- Galton, Dyke and Kurochkin, 2009. Re-analysis of Lower Cretaceous
fossil birds from the UK reveals an unexpected diversity. Journal of Vertebrate
Paleontology. 29(3), 102A.
unnamed Enantiornithes (Sanz, Chiappe, Fernadez-Jalvo, Ortega,
Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001)
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Material- (LH 11386 bird 3) (juvenile) distal tibia, astragalus, phalanx
I-1, pedal ungual I, metatarsal II, metatarsal III, metatarsal IV, phalanx IV-1,
phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal phalanges,
pedal ungual (Sanz, Chiappe, Fernadez-Jalvo, Ortega,
Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001)
(MCCMLH31444) incomplete radius, incomplete ulna, incomplete
carpometacarpus, phalanx I-1, incomplete manual ungual I, phalanx II-1, phalanx
II-2, manual ungual II, manual claw sheath, phalanx III-1, phalanx III-2, skin,
muscles, body feathers, remiges (Navalon, Marugon-Lobon, Chiappe, Sanz and Buscalioni,
2015)
Comments- LH 11386 bird 3 is one of the two most fragmentary of four juvenile
birds found associated in a theropod or pterosaur pellet. It was only identified
as a bird by Sanz et al. (2001), and is the specimen on the right which is colored
black in their illustration. The medial tibiotarsal condyle being wider than
the lateral one is only seen in Patagopteryx among euornithines. Also,
the proximal end of metatarsal III is in the same plane as metatarsals II and
IV, which is only seen in Patagopteryx, Archaeorhynchus and Hongshanornis
among euornithines. Metatarsal IV being so narrow compared to II and III
is uniquely enantiornithine. Where exactly it fits among Enantiornithes must
await further description or better illustration.
References- Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza
and Perez-Moreno, 2001. An Early Cretaceous pellet. Nature. 409, 998-999.
Navalon, Marugon-Lobon, Chiappe, Sanz and Buscalioni, 2015.
Soft-tissue and dermal arrangement in the wing of an Early Cretaceous bird:
Implications for the evolution of avian flight. Scientific Reports. 5, 14864.
unnamed Enantiornithes (Buffetaut, 1998)
Late Campanian-Early Maastrichtian, Late Cretaceous
Massecaps, Herault, France
Material- (ACAP-M 192) incomplete coracoid
(ACAP-M 193) proximal femur
Comments- These were described by Buffetaut (1998) as enantiornithines
and stated to resemble Enantiornis most closely. Walker et al. (2007)
noted they could be referrable to the similarly sized Martinavis from
the same strata, and described more precise similarities between ACAP-M 192
and Enantiornis, and ACAP-M 193 and unnamed Lecho Formation femora. Whether
these similarities (reduced acrocoracoid; robust coracoid head; supracoracoid
foramen does not open into dorsal fossa; well developed trochanteric crest;
deeply excavated proximolateral surface of femur) are synapomorphic requires
further study.
References- Buffetaut, 1998. First evidence of enantiornithine birds
from the Upper Cretaceous of Europe: Postcranial bones from Cruzy (Herault,
Southern France). Oryctos. 1, 131-136.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
unnamed Enantiornithes (Osi, 2004)
Santonian, Late Cretaceous
Csehbanya Formation, Hungary
Material- (MTM V.2002.05) incomplete femur (22 mm) (Osi, 2004)
(MTM V.2009.39.1) distal humerus (Dyke and Osi, 2010)
References- Osi, 2004. Enantiornithine bird remains from the Late Cretaceous
of Hungary. Sixth International Meeting of the Society of Avian Palaeontology
and Evolution, Abstracts. 50.
Osi, 2008. Enantiornithine bird remains from the Late Cretaceous of Hungary.
Oryctos. 7, 55-60.
Dyke and Osi, 2010. A review of Late Cretaceous fossil birds from Hungary. Geological
Journal. 45(4), 434-444.
unnamed probable enantiornithine (Nessov, 1988)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (ZIN PO 3473) axis (13.5 mm)
Comments- Nessov (1988, 1992a) originally assigned this axis to Aves,
then later (1992b) stated it was similar to Gaviidae. Kurochkin (1996) assigned
it to Alexornithidae within Enantiornithines. This was based on several characters-
general elongation; poorly developed prezgyapophyseal facets; lateral extensions
of the prezgyapophyseal facets; broad neural arch; dorsally flat posterior neural
arch that is projected posteriorly; low neural spine; shallow lateral central
fossa. These were compared favorably to Gobipteryx (his Nanantius
valifanovi) which he included in Alexornithidae, but it should be noted
how few enantiornithine axes are known and described. The axis of Hebeiornis
shares the poorly developed prezygapopgyses, lateral prezgyapophyseal extensions
and broad neural arch, though it is less elongate and seemingly has a less posteriorly
extensive neural arch. That of LP-4450-IEI has the broad neural arch and low
neural spine, but is less elongate. Those of GMV-2158, Eocathayornis
and Eoenantiornis are much shorter, but cannot be compared otherwise.
Additionally, many of the characters have a broader distribution. Both Confuciusornis
and Patagopteryx have axes with low neural spnes and shallow lateral
fossae, for instance. It is tentatively retained here as an enantiornithine
closer to Gobipteryx than the other taxa mentioned above based on elongation,
but it should be compared to a wider range of coelurosaurs as well.
References- Nessov, 1988. [New Cretaceous and Paleogene birds of Soviet
Middle Asia and Kazakhstan and their environments] Trudy Zoologicheskogo Instituta.
182, 31-38.
Nessov, 1992a. Mesozoic and Paleogene birds of the USSR and their
paleoenvironments. In Campbell (ed.). Papers in Avian Paleontology
Honoring Pierce Brodkorb. Natural History Museum of Los Angeles County
Science Series. 36, 465-478.
Nessov, 1992b. Review of localities and remains of Mesozoic and Paleogene birds
of the USSR and the description of new findings. Russkii Ornitologicheskii Zhurnal.
1(1), 7-50.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
unnamed enantiornithine (Balanoff, Norell, Grellet-Tinner and Lewin,
2008)
Santonian-Campanian?, Late Cretaceous
Javkhlant Formation, Mongolia
Material- (IGM 100/2010) (embryo) quadrate?, occiput or cervical neural
arch, three dorsal vertebrae, two dorsal centra, partial scapula?, coracoids
(one partial), furcular fragement?, humeri (~17-18 mm), radius (18.5 mm), ulnae,
femora (13.4, 13 mm), tibiae (15.5, 15.6 mm), metatarsi (8.8, 8.3 mm), fragments,
egg (~47.5x22.3 mm)
Comments- Balanoff and Norell (2006) and Balanoff et al. (2008) originally
described and assigned this specimen to Neoceratopsia, but reidentified as an
enantiornithine by Varricchio et al. (2015). The humeri, femora, tibiae and
fibula were reidentified as the femora, humeri, ulnae and radius respectively,
and cervical vertebrae were reidentified as dorsals. The supposed predentary
may be the median area of a furcula, the supposed qudrate may be correctly identified,
and the occiput may be that or a cervical neural arch.
References- Balanoff and Norell, 2006. Embryonic ornithischian from the
Upper Cretaceous on Mongolia. Journal of Vertebrate Paleontology. 26(3), 38A-39A.
Balanoff, Varricchio and Norell, 2008 online. Enantiornithine Bird,
Digital Morphology.
http://digimorph.org/specimens/enantiornithine_embryo/
Balanoff, Norell, Grellet-Tinner and Lewin, 2008. Digital preparation of a probable
neoceratopsian preserved within an egg, with comments on microstructural of
ornithischian eggshells. Naturwissenschaften. 95, 493-500.
Varricchio, Balanoff and Norell, 2015. Reidentification of avian embryonic remains
from the Cretaceous of Mongolia. PLoS ONE. 10(6), e0128458.
unnamed Enantiornithes (Kurochkin, 1999)
Late Campanian-Early Maastrichtian, Late Cretaceous
Gurilin Tsav, Nemegt Formation, Mongolia
Material- (PIN 4499-15) distal radius
(PIN 4499-16) distal ulna
(PIN 4499-18) distal carpometacarpus
Reference- Kurochkin, 1999. A new large enantiornithid from the Upper
Cretaceous of Mongolia (Aves, Enantiornithes). Russian Academy of Sciences,
Proceedings of the Zoological Institute. 277, 130-141.
undescribed enantiornithine (Hu, Gao, Xu and Hou, 2015)
Late Hauterivian, Early Cretaceous
Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Material- (CSFM-B00002) (juvenile) incomplete skeleton including skull,
mandible, sacrum, coracoid, sternum, forelimb, hindlimb and retrices
Diagnosis- (after Hu et al., 2015) snout half length of skull; upper
teeth more numerous than dentary teeth; lateral margin of coracoid straight;
posterior end of posteromedian sternal process forked laterally in goblet-like
shape; forelimb ~115% of hindlimb length; manual digit I not extending to end
of metacarpal II; metatarsals III and IV subequal in length; pedal digit III
longer than metatarsal III; pair of strap-like retrices tapered distally.
Reference- Hu, Gao, Xu and Hou, 2015. A new enantiornithine specimen
from the Lower Cretaceous of northern Hebei, China. Journal of Vertebrate Paleontology.
Program and Abstracts 2015, 147.
undescribed Enantiornithes (Zheng, Zhou, Wang, Zhang, Zhang, Wang, Wei,
Wang and Xu, 2013)
Barremian-Albian, Early Cretaceous
Jehol Group, China
Material- (STM 7-05) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-10) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-38) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-40) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-43) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-44) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-46) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-47) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-49) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-50) skull, mandible, cervical vertebrae, dorsal vertebrae,
dorsal ribs, synsacrum, caudal vertebrae, pygostyle, coracoids, furcula, humerus,
radius, ulnae, incomplete manus, pubes, femur, tibiotarsus, fibulae, pedal ungual
I, tarsometatarsi, phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1,
phalanx III-2, phalanx III-3, pedal ungual III, pedal phalanges, pedal unguals,
pedal claw sheaths, body feathers, retrices, remiges (Zheng, Zhou, Wang, Zhang,
Zhang, Wang, Wei, Wang and Xu, 2013)
(STM 7-54) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-61) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-62) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-66) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-63) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-68) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-72) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-73) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-78) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-93) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-98) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-104) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-108) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-113) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-116) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-121) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-123) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-112) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-123) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-136) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-138) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-160) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-161) skull, mandibles, cervical vertebrae, dorsal vertebrae, pygostyle,
partial scapulae, partial coracoids, furcula, humeri, radii, ulnae, manus, femora,
tibiotarsi, metatarsals I, phalanges I-1, pedal ungual I, tarsometatarsi, phalanges
II-1, phalanges II-2, pedal ungual II, phalanges III-1, phalanx II-2, phalanges
IV-1, body feathers, remiges (Zheng, Zhou, Wang, Zhang, Zhang, Wang, Wei, Wang
and Xu, 2013)
(STM 7-162) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-168) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-175) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-176) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-177) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-184) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-188) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-189) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-191) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-192) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-194) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-200) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-204) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-209) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-210) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-213) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-214) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-215) cervical vertebrae, synsacrum, caudal vertebrae, pygostyle, humeri,
ulnae, manus, femur, tibiotarsi, metatarsals I, phalanges I-1, pedal ungual
I, tarsometatarsi, phalanx II-1, phalanx II-2, pedal ungual II, phalanges III-1,
phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-4, pedal unguals
IV, body feathers, retrices, remiges (Zheng, Zhou, Wang, Zhang, Zhang, Wang,
Wei, Wang and Xu, 2013)
(STM 7-219) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-226) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-227) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-230) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-235) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-237) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-243) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-244) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-256) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-258) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-261) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-262) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-267) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-269) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-270) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-271) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-273) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-274) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-280) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-281) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-283) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-284) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 7-286) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-12) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-16) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-19) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-23) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-28) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-31) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-33) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-34) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-45) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-63) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-64) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-79) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-82) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-85) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-89) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-100) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-102) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-106) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-108) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-121) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-122) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-136) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-137) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-140) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-142) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 8-143) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-4) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-5) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-8) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-10) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-11) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-19) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-22) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-29) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-33) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-36) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 10-38) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-1) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-4) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-5) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-6) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-7) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-8) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-9) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-10) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-11) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-13) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-14) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-15) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-17) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-18) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-81) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-85) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-86) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-95) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-103) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-125) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-127) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-134) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-151) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-154) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-156) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-163) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-165) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-167) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-171) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-172) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-179) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-184) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-186) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-188) specimen including dorsal vertebrae, dorsal ribs, scapulae, coracoids,
furcula, sternum, anterolateral sternal process, sternal ribs and humeri (Zheng,
Wang, O'Connor and Zhou, 2012)
(STM 11-199) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-201) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-204) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-210) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 11-213) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 24-1) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 25-6) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 25-8) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 29-8) (female) specimen including pygostyle, humerus, ovarian
follicles and retrices (Zheng, O'Connor, Wang, Pan, Wang, Wang and
Zhou, 2017)
(STM 34-1) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 34-7) specimen including pygostyle and retrices (Wang et al., 2021 online)
(STM 34-12) specimen including pygostyle and retrices (Wang et al., 2021 online)
References- Zheng, Wang, O'Connor and Zhou, 2012. Insight into the early
evolution of the avian sternum from juvenile enantiornithines. Nature Communications.
3, 1116.
Zheng, Zhou, Wang, Zhang, Zhang, Wang, Wei, Wang and Xu, 2013. Hind
wings in basal birds and the evolution of leg feathers. Science. 339,
1309-1312.
Zheng, O'Connor, Wang, Pan, Wang, Wang and Zhou, 2017. Exceptional preservation of soft tissue in a new specimen of Eoconfuciusornis and its biological implications. National Science Review. 4(3), 441-452.
Wang, O'Connor, Zhao, Pan, Zheng, Wang and Zhou, 2021 online.
An Early
Cretaceous enantiornithine bird with a pintail. Current Biology. Online
now. DOI: 10.1016/j.cub.2021.08.044
unnamed enantiornithine (Chiappe and Ji, 2002)
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Material-
(GMV-2158) (juvenile) incomplete skull, incomplete mandibles,
incomplete hyoid, nine cervical vertebrae, ten or eleven dorsal
vertebrae, dorsal ribs, gastralia, six sacral vertebrae, seven or eight
caudal vertebrae, chevrons, incomplete scapulae (~9.9, ~10.2 mm),
partial coracoids (~7mm), furcula, incomplete sternum, lateral sternal
ossification, sternal ribs, incomplete humeri (15.5, 15.7 mm),
incomplete radii (14.6, 14.7 mm), partial ulna (15.6 mm), scapholunare,
pisiform, semilunate carpal, distal carpal III, metacarpal I (1.4 mm),
phalanx I-1 fragment, metacarpal II (6.9 mm), metacarpal III (7.2 mm),
partial ilium, pubes (~9.5 mm), ischia, femora (14.3 mm), incomplete
tibiae (18 mm), fibula (4.3 mm), astragalus, calacaneum, metatarsals I
(2.6 mm), fragmentary phalanges I-1, partial pedal ungual I,
metatarsals II (one incomplete; 10.1, 10.2 mm), phalanges II-1,
phalanges II-2 (one partial), pedal ungual II, incomplete metatarsals
III (11, 11.2 mm), phalanges III-1 (one fragmentary), phalanx II-2,
phalanx III-3, incomplete metatarsals IV, incomplete phalanges IV-1,
phalanx IV-2, partial phalanx IV-3, incomplete phalanx IV-4, incomplete
pedal ungual IV, incomplete phalanx, partial ungual, remiges, retrices
References- Chiappe and Ji, 2002. Enantiornithine (Aves) neonates from
the Early Cretaceous of China. Journal of Vertebrate Paleontology. 22(3), 43A.
Chiappe, Ji and Ji, 2007. Juvenile birds from the Early Cretaceous of China:
Implications for enantiornithine ontogeny. American Museum Novitates. 3594,
46 pp.
unnamed enantiornithine (Chiappe and Ji, 2002)
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Material- (GMV-2159) (juvenile) incomplete skull, sclerotic ring, mandibles,
seven cervical vertebrae, twelve dorsal vertebrae, dorsal ribs, seven sacral
vertebrae, six caudal vertebrae, pygostyle, scapula, coracoids (9.7, 9.8 mm),
furcula, anterior sternal ossification, sternum, lateral sternal ossification,
sternal ribs, humeri (20.7, 20.5 mm), radii (19.4, 19.6 mm), ulnae (20.8, 21.1
mm), scapholunares, pisiform, semilunate carpals, partial phalanges I-1, manual unguals
I, metacarpals II (9, 8.8 mm), phalanges II-1, phalanges II-2, manual unguals
II (9.2 mm), metacarpals III, phalanx III-1, pubes (12.5 mm), femora (17.2 mm),
tibiae (20.1, 21.6 mm), astragalus, metatarsals I (2.8, 2.7 mm), phalanges I-1,
pedal unguals I, metatarsals II (10.8, 10.7 mm), phalanges II-1, phalanges II-2,
pedal unguals II, metatarsals III (11.8, 11.8 mm), phalanges III-1, phalanges
II-2, phalanges III-3, pedal unguals III, phalanx IV-3, phalanx IV-4, pedal
ungual IV, remiges, retrices
References- Chiappe and Ji, 2002. Enantiornithine (Aves) neonates from
the Early Cretaceous of China. Journal of Vertebrate Paleontology. 22(3), 43A.
Chiappe, Ji and Ji, 2007. Juvenile birds from the Early Cretaceous of China:
Implications for enantiornithine ontogeny. American Museum Novitates. 3594,
46 pp.
undescribed Enantiornithes (Zhang and Zhou, 2004)
Mid Aptian, Early Cretaceous
Jingangshan Beds of Yixian Formation, Liaoning, China
Material- (IVPP V13939) skeleton including dorsal vertebrae, dorsal ribs,
synsacrum, four or five caudal vertebrae, pygostyle, radius, ulna, manus, ilia,
pubes, ischia, femora, tibiotarsi, tarsometatarsi, pedes, body feathers, remiges
(Zhang and Zhou, 2004)
(IVPP V14238) (embryo) skull, mandible, eight cervical vertebrae, eleven dorsal
vertebrae, dorsal ribs, six sacral vertebrae, nineteen caudal vertebrae, scapula,
coracoids, furcula, humeri, radius, ulna, semilunate carpal, metacarpal I, phalanx
I-1, manual ungual I, metacarpal II, phalanx II-1, phalanx II-2, manual ungual
II, metacarpal III, ilium, pubes, ischium, femora, tibiae, metatarsal I, phalanx
I-1?, metatarsals II, phalanx II-1, metatarsals III, phalanges III-1, phalanx
III-2, phalanx III-3, pedal ungual III, metatarsals IV, phalanx IV-1, phalanx
IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, remiges, retrices (egg ~35x20
mm) (Zhou and Zhang, 2004)
References- Zhang and Zhou, 2004. Leg feathers in an Early Cretaceous
bird. Nature. 431, 925.
Zhou and Zhang, 2004. A precocial avian embryo from the Lower Cretaceous of
China. Science. 306(5696), 653.
unnamed Enantiornithes (Hou, 1997)
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Material- (CNUVB-1001) skull, eight cervical vertebrae, dorsal vertebrae,
dorsal ribs, three uncinate processes, four caudal vertebrae, pygostyle, scapulae,
coracoids, furcula, sternum, sternal ribs, humeri (55.6 mm), radii, ulnae (60.8
mm), scapholunare, pisiform, carpometacarpi (26.4 mm), phalanges I-1, manual unguals
I, phalanges II-1, phalanges II-2, manual ungual II, phalanges III-1, ilium,
pubis, ischium, femora (40.4 mm), tibiotarsi (44.7 mm), fibula, phalanges I-1,
pedal unguals I, tarsometatarsi (23 mm), phalanges II-1, phalanges II-2, pedal
unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals
III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals
IV (Zhang, Chen, Zhang and Hou, 2014)
(DNHM D2130) incomplete skeleton including incomplete skull (O'Connor, 2009)
(DNHM D2836) incomplete skeleton including incomplete skull (O'Connor, 2009)
(DNHM D2884) incomplete skull, mandibles, cervical vertebrae, dorsal vertebrae,
dorsal ribs, uncinate processes, sacrum, caudal vertebrae, pygostyle, coracoid,
furcula, sternal ribs, humeri, radii, ulnae, pisiform, carpometacarpi, phalanges
I-1, manual unguals I, phalanges II-1, phalanges II-2, phalanges III-1, ilia,
femora, tibiotarsi, metatarsal I, phalanges I-1, pedal unguals I, tarsometatarsi,
phalanges III-1, phalanges III-2, phalanx III-3, pedal ungual III, pedal phalanges,
pedal unguals, body feathers, remiges and retrices (O'Connor, 2009)
(DMNH D2952; DMNH D2953) incomplete skeleton including incomplete skull (O'Connor,
2009)
(IVPP coll.) ?(IVPP coll.) ilium, pubis, ischium (Hou, 1997)
(STM 10-45) (female subadult) (105 g) skull, mandibles, five cervical vertebrae,
dorsal vertebra, three caudal vertebrae, pygostyle, scapulae, coracoids, furcula,
sternum, sternal ribs, humeri (40.4 mm), radii, ulnae, scapholunares, pisiforms, semilunate
carpals, metacarpals I, phalanges I-1, manual unguals I, metacarpals II, phalanges
II-1, phalanges II-2, manual ungual II, metacarpals III, phalanges III-1, femora
(31.5 mm), tibiae, proximal tarsals, phalanx I-1, pedal ungual I, tarsometatarsi,
phalanx II-2, pedal ungual II, phalanx III-3, pedal ungual III, phalanx IV-4,
pedal ungual IV, pedal phalanges, ovarian follicles (Zheng et al., 2013)
(STM 29-8) (female adult) (126 g) skull, mandible, hyoid, six cervical vertebrae,
dorsal vertebra, dorsal ribs, synsacrum, caudal vertebrae, pygostyle, furcula,
humeri (44.8 mm), radii, ulnae, scapholunare, pisiform, carpometacarpi, phalanges I-1,
manual unguals I, phalanges II-1, phalanges II-2, manual ungual II, phalanx
III-1, ilium, pubis, ischium, femora (40.2 mm), tibiotarsi, pedal ungual I,
tarsometatarsi, phalanx II-2, pedal ungual II, pedal phalanx fragments, body
feathers, remiges, ovarian follicles (Zheng et al., 2013)
(STM 34-2) (juvenile) dorsal vertebrae, dorsal ribs, sacrum, caudal vertebrae,
pygostyle, scapulae, coracoids, furcula, sternum, lateral sternal ossifications,
sternal ribs, humeri, radii (one incomplete), ulnae (one incomplete), metacarpal
I, phalanx I-1, manual ungual I, metacarpal II, phalanx II-1, phalanx II-2,
manual ungual II, metacarpal III, ischia, femora, tibiae, metatarsal I, metatarsal
II, phalanx II-1, metatarsal III, phalanx III-1, metatarsal IV, phalanx IV-1,
body feathers, remiges (Zheng, Wang, O'Connor and Zhou, 2012)
(STM 34-9) (juvenile) skull, mandible, cervical vertebrae, dorsal vertebrae,
dorsal ribs, sacrum, caudal vertebrae, pygostyle, scapulae, coracoids, anterior
sternal ossification, sternum, lateral sternal ossification, sternal ribs, humeri,
radii, ulnae, scapholunare, pisiforms, semilunate carpals, metacarpals I, phalanges
I-1, manual unguals I, metacarpals II, phalanges II-1, phalanges II-2, manual
ungual II, metacarpals III, phalanges III-1, iliu, incomplete pubis, ischium,
femora, tibiae, metatarsal I, phalanges I-1, pedal unguals I, metatarsals II,
phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges
III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV,
phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals
IV, pedal claw sheaths, body feathers, retrices (Zheng, Wang, O'Connor and Zhou,
2012)
skeleton including skull, tibiotarsus, pes, body feathers and retrices (Peteya,
Clarke, Li and Shawkey, 2015)
Early Albian, Early Cretaceous
Jiufotang Formation, Inner Mongolia, China
(IVPP V15036) (juvenile) specimen including dorsal vertebrae, dorsal ribs, scapulae,
coracoids, furcula, lateral sternal ossification, sternal rib and humeri (Zheng,
Wang, O'Connor and Zhou, 2012)
(IVPP V15564) (juvenile) specimen including dorsal vertebrae, dorsal ribs, coracoids,
furcula, sternum, lateral sternal ossifications, sternal ribs and humerus (Zheng,
Wang, O'Connor and Zhou, 2012)
(STM 34-1) (juvenile) skull, mandibles, hyoids, cervical vertebrae, dorsal vertebrae,
dorsal ribs, gastralia, sacrum, caudal vertebrae, chevrons, pygostyle, scapula,
coracoid, anterior sternal ossification, sternum, lateral sternal ossification,
sternal ribs, humeri, radii, ulnae, metacarpals II, phalanx II-1, phalanx II-2,
manual ungual II, metacarpals III, phalanx III-1, ilia, pubes, ischia, femora,
tibiae, astragalocalcaneum, metatarsal I, phalanges I-1, pedal ungual I, metatarsals
II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges
III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV,
phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals
IV, body feathers, remiges (Zheng, Wang, O'Connor and Zhou, 2012)
(STM 34-7) (juvenile) skull, cervical vertebrae, dorsal vertebrae, dorsal ribs,
sacrum, caudal vertebrae, pygostyle, coracoids, furcula, anterior sternal ossification,
sternum, lateral sternal ossification, sternal ribs, humeri, radii, ulnae, semilunate
carpal, metacarpal I, phalanx I-1, manual ungual I, metacarpals II, phalanges
II-1, phalanges II-2, manual unguals II, metacarpals III, phalanges III-1, ilia,
femora, tibiae (one incomplete), phalanx I-1, metatarsi, pedal phalanges, pedal
unguals, body feathers, retrices, remiges (Zheng, Wang, O'Connor and Zhou, 2012)
Comments- Hou (1997) includes a photograph of an articulated pelvis (IVPP
coll.) which was illustrated as Cathayornis yandica by Zhou (1999) and
Zhou and Hou (2002) without comment. It has a highly convex dorsal postacetabular
margin and large amount of taper, unlike Cathayornis, so is probably
wrongly referred.
Zhang et al. (2014) described a specimen they state is most similar to Pengornis
(large size; hooked acromion; large interclavicular angle; forelimb/hindlimb
ratio minus phalanges 1.32), but differs in- posteromedial sternal processes;
more robust ulna; longer hallux.
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Zhou, 1999. Early evolution of birds and avian flight- Evidence from Mesozoic
fossils and modern birds. PhD thesis, University of Kansas. 216 pp.
Zhou and Hou, 2002. The discovery and study of Mesozoic birds in China. In Chiappe
and Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London. 160-183.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
O'Connor, Chiappe, Chuong, Bottjer and You, 2012. Homology and potential cellular
and molecular mechanisms for the development of unique feather morphologies
in early birds. Geosciences. 2, 157-177.
Zheng, Wang, O'Connor and Zhou, 2012. Insight into the early evolution of the
avian sternum from juvenile enantiornithines. Nature Communications. 3, 1116.
Zheng, O'Connor, Huchzermeyer, Wang, Wang, Wang and Zhou, 2013. Exceptional
preservation of ovarian follicles in Early Cretaceous birds and implications
for early evolution of avian reproductive behaviour. Nature. 495, 507-511.
O'Connor, Wang, Zheng, Wang and Zhou, 2014. The histology of two female Early
Cretaceous birds. Vertebrata PalAsiatica. 52(1), 112-128.
Zhang, Chen, Zhang and Hou, 2014. A large enantiornithine bird from the Lower
Cretaceous of China and its implication for lung ventilation. Biological Journal
of the Linnean Society. 113, 820-827.
Peteya, Clarke, Li and Shawkey, 2015. New details on the plumage and coloration
of an Early Cretaceous enantiornithine bird. Journal of Vertebrate Paleontology.
Program and Abstracts 2015, 194.
unnamed Enantiornithes (O'Connor, Chiappe, Ji and You, 2004)
Late Aptian, Early Cretaceous
Xiagou Formation, Gansu, China
Material- (CAGS-IG-02-0901) incomplete scapula, coracoid (19 mm), humerus
(47.7 mm), radius (47.4 mm), ulna (49.4 mm), scapholunare, pisiform, carpometacarpus
(I 3.7, II 19, III 21.5 mm), phalanx I-1, phalanx II-1 (11.1 mm), phalanx II-2
(7.9 mm), manual ungual II (6.6 mm), phalanx III-1 (4.6 mm), fragments (O'Connor,
Chiappe, Ji and You, 2004)
(CAGS-IG-04-CM-023) partial humerus, radius (32.2 mm), ulna (33.6 mm),
scapholunare, pisiform, carpometacarpus (17.1 mm; I 2.8, II 14.1 mm),
phalanx I-1 (5.6 mm), manual ungual I (4.1 mm), phalanx II-1 (7.9 mm),
phalanx II-2 (6.1 mm), manual ungual II (5.2 mm), phalanx III-1 (5 mm),
phalanx III-2 (Harris, Lamanna, You, Ji and Ji, 2006)
(CAGS-IG-05-CM-012) pelvis, partial hindlimbs (O'Connor, 2009)
(CAGS-IG-07-CM-001) dorsal vertebra, dorsal rib fragment, synsacrum, caudal
vertebrae, pygostyle, ilia, ischium (14.2 mm), femora (26.3 mm), tibiotarsi
(34.4 mm), fibula, metatarsals I (~5.4 mm), phalanges I-1 (5.4 mm), pedal unguals
I (5.2 mm), tarsometatarsi (21.6 mm; II 20.4, III 21.6, IV 20.8 mm), phalanges
II-1 (4.7 mm), phalanges II-2 (5.8 mm), pedal unguals II (5.9 mm), phalanges
III-1 (5.9 mm), phalanges III-2 (5.3 mm), phalanges III-3 (5.9 mm), pedal unguals
III (5.8 mm), phalanges IV-1 (3.4 mm), phalanges IV-2 (2.7 mm), phalanges IV-3
(3.1 mm), phalanges IV-4 (4.3 mm), pedal unguals IV (~5.1 mm), body feathers,
retrices (O'Connor, 2009)
(CAGS coll.) two specimens (Lamanna et al., 2009)
Comments- Note Ji et al. (2011) later described the Xiagou Qiliania as
an enantiornithine, though it is placed more conservatively as Pygostylia incertae
sedis here. Given that it is based on two specimens, this leaves six undescribed
enantiornithines noted by Lamanna et al. (2009) (out of their 11 total). The three
numbered specimens listed by O'Connor (2009) probably encompass the two posterior
skeletons (one including retrices, another including feathers and pedal claw
sheaths) mentioned by Lamanna et al. (2009). Indeed, CAGS-IG-07-CM-001 can be
inferred to be the specimen including retrices by its mention and illustration
in O'Connor et al. (2012), and its measurements are listed in O'Connor et al.
(2015). The other specimen is confirmed to be CAGS-IG-05-CM-004 by O'Connor
et al. (2015), who described it as Feitianius. CAGS-IG-05-CM-030 being
described as Dunhuangia (Wang et al., 2015) further lowers the number
of unpublished specimens. Avimaia
was described based on IVPP 25371 with the paratype CAGS-IG-04-CM-007
orioginally being described without a name by Lammana et al. (2006).
References- O'Connor, Chiappe, Ji and You, 2004. New enantiornithine
bird from the Early Cretaceous of Gansu Province, Northwestern China. Journal
of Vertebrate Paleontology. 24(3), 244A-245A.
You, O'Connor, Chiappe and Ji, 2005. A new fossil bird from the Early Cretaceous
of Gansu Province, Northwestern China. Historical Biology. 17, 7-14.
Harris, Lamanna, You, Ji and Ji, 2006. A second enantiornithean (Aves: Ornithothoraces)
wing from the Early Cretaceous Xiagou Formation near Changma, Gansu Province,
People’s Republic of China. Canadian Journal of Earth Sciences. 43, 547-554.
Lamanna, You, Harris, Chiappe, Ji, L� and Ji, 2006. A partial skeleton
of an enantiornithine bird from the Early Cretaceous of Northwestern China.
Acta Palaeontologica Polonica. 51(3), 423-434.
Lamanna, Li, Harris, Atterholt and You, 2009. Exceptionally preserved Enantiornithes
(Aves: Ornithothoraces) from the Early Cretaceous of Northwestern China. Journal
of Vertebrate Paleontology. 29(3), 131A.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Ji, Atterholt, O'Connor, Lammana, Harris, Li, You and Dodson, 2011. A new, three-dimensionally
preserved enantiornithine bird (Aves: Ornithothoraces) from Gansu Province,
north-western China. Zoological Journal of the Linnean Society. 162, 201-219.
O'Connor, Chiappe, Chuong, Bottjer and You, 2012. Homology and potential cellular
and molecular mechanisms for the development of unique feather morphologies
in early birds. Geosciences. 2, 157-177.
O'Connor, Li, Lamanna, Wang, Harris, Atterholt and You, 2015. A new Early Cretaceous
enantiornithine (Aves, Ornithothoraces) from northwestern China with elaborate
tail ornamentation. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2015.1054035
Wang, Li, O'Connor, Zhou and You, 2015. Second species of enantiornithine bird
from the Lower Cretaceous Changma Basin, northwestern China with implications
for the taxonomic diversity of the Changma avifauna. Cretaceous Research. 55,
56-65.
undescribed enantiornithine (Zheng, Zhang and Hou, 2007)
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China
Material- (STM V001) incomplete skull, sclerotic ring, seven cervical
vertebrae, incomplete coracoid, proximal humerus, body feathers
Comments- Zheng et al. (2007) state the skull of Paraprotopteryx's
holotype "seems not to be the same individual as the postcranial bones
after careful examination", and the portion of the slab containing the
skull and cervical vertebrae does seem to contain an additional left coracoid.
Reference- Zheng, Zhang and Hou, 2007. A new enantiornithine bird with
four long retrices from the Early Cretaceous of Northern Hebei, China. Acta
Geologica Sinica. 81(5), 703-708.
unnamed enantiornithine (Zhang, Zhang, Li and Li, 2010)
Early Cretaceous
Jingchuan Formation, Inner Mongolia, China
Material- (OFMB-3) two vertebrae, four dorsal ribs, furcula, sternum
(23.1 mm), five sternal ribs (Zhang et al., 2010)
Comments- Zhang et al. (2010) referred a new specimen (OFMB-3) from the
same locality to Cathayornis chabuensis, interpreting the differences
(broadly triangular distal expansions of the posterolateral sternal processes;
post-costal sternal processes) as being due to greater ontogenetic age. Wang
and Liu (2016) suggested this could not be demonstrated, and given the lack
of shared characters with chabuensis, declared OFMB-3 indeterminate.
References- Zhang, Zhang, Li and Li, 2010. New discovery and flying skills
of Cathayornis from the Lower Cretaceous strata of the Otog Qi in Inner
Mongolia, China. Geological Bulletin of China. 29(7), 988-992.
Wang and Liu, 2016 (online 2015). Taxonomical reappraisal of Cathayornithidae (Aves: Enantiornithes).
Journal of Systematic Palaeontology. 14(1), 29-47.
undescribed possible enantiornithine (Unwin and Matsuoka, 2000)
Valanginian-Hauterivian, Early Cretaceous
Kuwajima Formation of the Tetori Group, Japan
Material- (SBEI 307) fragmentary humerus
Comments- Originally described in Japanese by Unwin and Matsuoka (2000),
who also figured the bone. Matsuoka et al. (2002) referred to this as a bird
based on its lack of torsion and Enantiornithes based on the lack of an anteriorly
bulbous head. However, the former is actually present in most enantiornithines
(with some exceptions like Elsornis, Neuquenornis and Enantiornis)
and the latter character is symplesiomorphic for theropods. Unwin and Matsuoka's
figure shows a capital groove and concave proximal border to the humeral head
though, which agree with enantiornithine anatomy.
References- Unwin and Matsuoka, 2000. Pterosaurs and birds. In Matsuoka
(ed.). Fossils of the Kuwojima "Kasekikabe" (Fossil-bluff): Scientific
report on a Neocomian (Early Cretaceous) fossil assembrage from the Kuwajima
Formation, Tetori Group, Shiramine, Ishikawa, Japan. Shiramine Village Board
of Education, Ishikawa. 99-104.
Matsuoka, Kusuhashi, Takada and Setoguchi, 2002. A clue to the Neocomian vertebrate
fauna: Initial results from the Kuwajima 'Kaseki-kabe' (Tetori Group) in Shiramine,
Ishikawa, central Japan. Memoirs of the Faculty of Science, Kyoto University,
Series of Geology and Mineralogy. 59(1), 33-45.
undescribed Enantiornithes (Li and Gao, 2007)
Barremian-Albian, Early Cretaceous
Sinuiju Series, North Korea
Material- ? distal tibiotarsus, metatarsal I, phalanx I-1, pedal ungual
I, metatarsals II, phalanges II-1, phalanges II-2, metatarsals III, phalanges
III-1, phalanges III-2, phalanges III-3, metatarsals IV, phalanges IV-1, phalanges
IV-2, phalanges IV-3, phalanges IV-4, pedal ungual IV (Gao et al., 2009)
? specimen including caudal vertebrae, pygostyle (~35 mm), forelimb material
including manual ungual, manual claw sheath, partial ilium, femur, tibiotarsus
(~50 mm), tarsometatarsus and pedal ungual (Gao et al., 2009)
several specimens (Li and Gao, 2007)
Comments- Li and Gao (2007) reported several enantiornithine specimens
are known from the Sinuijiu Series, two of which are illustrated and commented
on by Gao et al. (2009). The latter referred the hindlimb specimen to Enantiornithes
based on- unfused metatarsus; metatarsal II much shorter than III or IV; metatarsals
III and IV equal in length. Yet these are primitive characters, and as the fourth
metatarsal isn't very reduced in width, this may be another kind of bird such
as a confuciusornithid. The large pedal ungual I indicates this is probably
an ornithine though. The second photographed specimen isn't identified past
being a bird, but while the long pygostyle suggests it is enantiornithine or
confuciusornithid, the large manual ungual is more similar to the latter clade.
References- Li and Gao, 2007. Lower Cretaceous vertebrate fauna from
the Sinuiju basin, North Korea as evidence of geographic extension of the Jehol
biota into the Korean peninsula. Journal of Vertebrate Paleontology. 27(3),
106A.
Gao, Li, Wei, Pak and Pak, 2009. Early Cretaceous birds and pterosaurs from
the Sinuiju series, and geographic extension of the Jehol biota into the Korean
peninsula. Journal of the Paleontological Society of Korea. 25(1), 57-61.
unnamed Enantiornithes (Xing, McKellar, Wang, Bai, O'Connor, Benton, Zhang, Wang, Tseng, Lockley, Li, Zhang and Xu, 2016)
Early Cenomanian, Late Cretaceous
Angbamo, Myanmar
Material- (DIP-V-15100)
(juvenile) incomplete radius, incomplete ulna, metacarpal I (1.00 mm),
phalanx I-1 (1.83 mm), manual ungual I (1.28 mm), metacarpal II (4.17
mm), phalanx II-1 (2.22 mm), phalanx II-2 (1.78 mm), manual ungual II
(1.28 mm), metacarpal III (3.72 mm), phalanx III-1 (1.00 mm), manual
claw sheaths, skin, contour feathers, remiges (Xing, McKellar, Wang,
Bai, O'Connor, Benton, Zhang, Wang, Tseng, Lockley, Li, Zhang and Xu,
2016)
(DIP-V-15101) (juvenile) distal metacarpal I?, phalanx I-1, manual
ungual I (1.81 mm), metacarpal II (4.95 mm), phalanx II-1 (3.10 mm),
phalanx II-2 (2.57 mm), manual ungual II (2.14 mm), metacarpal III
(6.24 mm), phalanx III-1 (1.38 mm), manual claw sheaths, skin, contour
feathers, remiges (Xing, McKellar, Wang, Bai, O'Connor, Benton, Zhang,
Wang, Tseng, Lockley, Li, Zhang and Xu, 2016)
?(DIP-V-15102) posterodorsal skull, about five cervical vertebrae,
nine-ten dorsal vertebrae, sacral vertebra, few caudal vertebrae,
pygostyle, distal humerus, radius, ulna, scapholunare, proximal
carpometacarpus, phalanx I-1?, ilia, pubes, ischium, femur, contour
feathers, remiges (Xing, O'Connor, McKellar, Chiappe, Bai, Tseng,
Zhang, Yang, Fang and Li, 2018)
(DIP-V-15105a) metatarsal I, phalanx I-1, pedal ungual I, distal
metatarsal II, phalanx II-1, phalanx II-2, pedal ungual II, distal
metatarsal III, phalanx III-1, phalanx III-2, phalanx III-3, proximal
pedal ungual III, distal metatarsal IV, phalanx IV-1, phalanx IV-2,
phalanx IV-3, phalanx IV-4, proximal pedal ungual IV, pedal claw
sheaths, contour feathers, skin, scutellae
....(DIP-V-15105b) partial remiges (Xing, McKellar, O'Connor, Bai, Tseng and Chiappe, 2019a)
(HPG-15-1) (hatchling) skull, mandibles, dentary beak, atlas, axis,
third to sixth cervical vertebrae, cervical ribs, distal radius, distal
ulna, scapholunare, pisiform, metacarpal I, phalanx I-1, manual ungual I,
metacarpal II, phalanx II-1, phalanx II-2, manual ungual II, metacarpal
III, phalanx III-1, proximal femur, distal tibia, astragalus, ascending
process, calcaneum, distal tarsal IV, partial phalanges I-1, pedal
unguals I (one incomplete), distal tarsal III fused with metatarsal IIs
(one partial), phalanges II-1, phalanges II-2, pedal unguals II (one
proximal), metatarsals III (one partial), phalanx III-1, proximal
phalanx III-2, phalanx III-3, pedal ungual III, metatarsal IV (one
partial), phalanx IV-1, phalanges IV-2, phalanges IV-3 (one proximal),
phalanges IV-4, pedal unguals IV, pedal claw sheaths, skin, scutellae,
contour feathers, remiges, retrix (Xing, O'Connor, McKellar, Chiappe,
Tseng, Li and Bai, 2017)
Comments- All of these specimens are preserved in amber, as were the named Fortipesavis prehendens (YLSNHM01001; Clark and O'Connor, 2021) and Elektorornis chenguangi (HPG-15-2; Xing et al., 2019c).
DIP-V-15100 and 15101 were found in 2015 and consist of juvenile wings
(Xing et al., 2016). "Preserved feather colour in DIP-V-15100
appears dark brown in the alula, and is slightly paler in the primaries
and secondaries ... Dorsal contour feathers are generally dark in
colour, but those basal to the alula may have been pale or white ...
Ventrally, the surface of the wing has a strong contrast between white
or pale contour feathers and down adjacent to the dark brown contour
feathers along the anterior margin of the wing." "DIP-V-15101
shares a pale or white spot among the feathers just basal to its
well-developed alula ... better-defined bands of pale feathers extend
across the dorsal surface of DIP-V-15101, posteriorly and distally from
the apex of the alula, and along the trailing edge of the wing."
On "the ventral wing surface ... the base of the alular digit is
clearly surrounded by white under marginal coverts (Fig. 3c), and this
plumage continues posteriorly, as a mixture of pale or white
plumulaceous feathers."
Xing et al. (2017) describe enantiornithine hatchling HPG-15-1
discovered by January 2017. "Unfeathered regions ... include most
of the postauricular, auricular (anterior to the external ear opening),
malar, and submalar areas", while "the ventral surface of the manus
lacks plumage, and the exposed skin has a mottled grey, tan, and black
surface." "The individual feathers in each [cervical] tract are
dark brown in color", "feathers from the lateral pectoral tract are ...
elongate, pale or
white contours", "plumage within the femoral and crural tracts ... are
nearly transparent, suggesting that they were pale or white" and
"interspersed among the neoptile [hindlimb] plumage are isolated
bristle-like filaments (IBFs) of a medium brown color."
Considering wing and tail color, "each of the complete primaries is
preserved with visible color patterning that consists of a walnut brown
color interrupted by a pale feather apex and two pale transverse bands
in the distal half of the feather", "the central core and apical margin
of each secondary feather is preserved with a pale brown color, while
the lateral margins of each vane are preserved with amuch darker walnut
brown color", and "the lateral margins [of the tail] bear a row of
unpigmented (pale or white) feathers."
Xing et al. (2018) describe poorly preserved specimen
DIP-V-15102. "The barbule apices among the head feathers are
preserved with a diffuse, dark brown pigmentation, while the barbule
bases and barb rami appear to have been pale or unpigmented." On
feathers which "presumably stem from the shoulder or breast regions"
pigmentation "is uniform across all feather regions, appearing pale
brown and diffuse." In primary remiges "barbules, rami, and
rachises are all diffuse, pale brown in colour", while secondaries "may
have more of a reddish-brown apparent coloration."
Xing et al. (2019a) describe enantiornithine pes and wing fragment
DIP-V-15105. On the foot "contour feathers are preserved with a
dark brown overall colouration", while filaments between scutellae
"were either white or pale in life." The pedal proportions are
different from Elektorornis or HPG-15-1, while there are ten primaries unlike DIP-V-15100 or 15101 which each have nine.
References- Xing, McKellar, Wang, Bai, O'Connor, Benton, Zhang, Wang, Tseng,
Lockley, Li, Zhang and Xu, 2016. Mummified precocial bird wings in
mid-Cretaceous Burmese amber. Nature Communications. 7:12089.
Xing, O'Connor, McKellar, Chiappe, Tseng, Li and Bai, 2017. A
mid-Cretaceous enantiornithine (Aves) hatchling preserved in Burmese
amber with unusual plumage. Gondwana Research. 49, 264-277.
Xing, O'Connor, McKellar, Chiappe, Bai, Tseng, Zhang, Yang, Fang and
Li, 2018. A flattened enantiornithine in mid-Cretaceous Burmese amber:
Morphology and preservation. Science Bulletin. 63(4), 235-243.
Xing, McKellar, O'Connor, Niu and Mai, 2019b. A mid-Cretaceous
enantiornithine foot and tail feather preserved in Burmese amber.
Scientific Reports. 9:15513.
Xing, McKellar, O'Connor, Bai, Tseng and Chiappe, 2019a. A fully
feathered enantiornithine foot and wing fragment preserved in
mid-Cretaceous Burmese amber. Scientific Reports. 9:927.
Xing, O’Connor, Chiappe, McKellar, Carroll, Hu, Bai and Lei, 2019c. A
new enantiornithine bird with unusual pedal proportions found in amber.
Current Biology. 29(14), 2396-2401.e2.
Clark and O'Connor, 2021. Exploring the ecomorphology of two Cretaceous
enantiornithines with unique pedal morphology. Frontiers in Ecology and
Evolution. 9:654156.
unnamed Enantiornithes (Forster and O'Connor, 2000; described by O'Connor
and Forster, 2010)
Middle Maastrichtian, Late Cretaceous
Anembalemba Member of Maevarano Formation, Madagascar
Material- (FMNH PA 747; Humeral Taxon C) humerus (44.6 mm) (O'Connor and
Forster, 2010)
(FMNH PA 752) femur (32.5 mm) (O'Connor and Forster, 2010)
(FMNH PA 753) incomplete metatarsal III, partial metatarsal IV (O'Connor and
Forster, 2010)
(FMNH PA 780) carpometacarpus (23.2 mm) (O'Connor and Forster, 2009; described
by O'Connor and Forster, 2010)
(UA 9605; Humeral Taxon D) partial humerus (O'Connor and Forster, 2010)
(UA 9606; Humeral Taxon E) humeral fragment (O'Connor and Forster, 2010)
(UA 9608) proximal ulna (O'Connor and Forster, 2010)
Comments- Forster and O'Connor (2000) first reported most Maevarano bird
elements were enantiornithine, referencing what are probably humeral taxa C
and D (small, with large bicipital crests, ventral tubers, and m. coracobrachialis
scars). Carpometacarpus FMNH PA 780 was reported by O'Connor and Forster (2009)
as enantiornithine. The carpometacarpus may belong to Vorona, though
the other remains are clearly not Rahonavis or Vorona.
References- Forster and O'Connor, 2000. The avifauna of the Upper Cretaceous
Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 20(3),
41A-42A.
O'Connor and Forster, 2009. The Late Cretaceous (Maastrichtian) avifauna from
the Maevarano Formation, Northwestern Madagascar: Recent discoveries and new
insights related to avian anatomical diversification. Journal of Vertebrate
Paleontology. 29(3), 157A.
O'Connor and Forster, 2010. A Late Cretaceous (Maastrichtian) avifauna from
the Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 30(4),
1178-1201.
unnamed enantiornithine (Schweitzer, Jackson, Chiappe, Calvo and Rubilar,
2001)
Santonian, Late Cretaceous
Bajo de la Carpa Formation of the Rio Colorado Subgroup, Neuquen, Argentina
Material- (MUCPv-284) (embryo) coracoid, partial furcula, incomplete
humerus, proximal radius, proximal ulna, ischia (~5 mm), distal femur, tibiae
(one fragmentary), egg (45x27 mm)
(MUCPv-305) egg
(MUCPv-306) egg
(MUCPv-350) partial egg
(MUCPv-351) partial egg
(MUCPv-352) partial egg
(MUCPv-353) partial egg
(MUCPv-354) partial egg
(MUCPv-355) partial egg
Comments-
Schweitzer et al. (2001, 2002) referred this specimen to
Enantiornithes. The strut-like coracoid indicates these are avialan
eggs, while the large proximodorsal ischial process is similar to
non-euornithine avialans. The laterally excavated furcula is only
known in enantiornithines. The dorsally projected deltopectoral crest
is unlike Aves as well as most more basal euornithines (except
ambiortids, Gansus and Ichthyornis).
The slender radius (compared to ulnar width) does not indicate bird affinities
though, as it is also found in many more basal maniraptorans. The specimens
could belong to the enantiornithine Neuquenornis from the same locality.
While the prismatic structure of the eggshell was noted as being like neognaths,
Gobipipus and troodontids are now known to have a similar construction.
The third structural layer is otherwise unique to euornithines where definitely
associated with skeletal material however.
References- Schweitzer, Jackson, Chiappe, Calvo and Rubilar, 2001. Cretaceous
avian eggs and embryos from Argentina. Journal of Vertebrate Paleontology. 21(3),
99A.
Schweitzer, Jackson, Chiappe, Schmitt, Calvo and Rubilar, 2002. Late Cretaceous
avian eggs with embryos from Argentina. Journal of Vertebrate Paleontology.
22(1), 191-195.
Grellet-Tinner, 2005. A phylogenetic analysis of oological characters: A case
study of saurischian dinosaur relationships and avian evolution. PhD thesis,
University of Southern California. 221 pp.
Grellet-Tinner, Chiappe, Norell and Bottjer, 2006. Dinosaur eggs and nesting
behaviors: A paleobiological investigation. Palaegeography, Palaeoclimatology,
Palaeoecology. 232, 294-321.
undescribed enantiornithine (Debee, Lawver, Clarke and Guillermo, 2010)
Maastrichtian, Late Cretaceous
La Colonia Formation, Chubut, Argentina
Material- (MPEF-PV 2359) distal humerus
Diagnosis- (after Debee et al., 2010) thin crest on ventral margin of
humerus (raised margin of m. brachialis insertion).
Comments- Debee et al. (2010) referred this specimen to Euenantiornithes.
Reference- Debee, Lawver, Clarke and Guillermo, 2010. A new enantiornithine
(Theropoda, Avialae) from the Upper Cretaceous La Colonia Formation of Patagonia,
Argentina. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 80A.
unnamed Enantiornithes (Walker, 1981)
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Material- (MACN-S-02) (Chiappe, 1996)
(PVL-4026) (Chiappe, 1996)
(PVL-4030) distal tibiotarsus (~57 mm) (Chiappe and Walker, 2002)
(PVL-4031) ulna (70.8 mm) (Chiappe, 1996)
(PVL-4032) distal ulna (~98 mm), proximal tibiotarsus (~92 mm) (Chiappe, 1996)
(PVL-4034) incomplete scapula (62 mm), coracoid (50 mm) (Chiappe and Walker,
2002)
(PVL-4036) femur (55 mm) (Chiappe and Calvo, 1994)
(PVL-4037) femur (77.8 mm) (Walker, 1981)
(PVL-4038) femur (75.6 mm) (Chiappe and Calvo, 1994)
(PVL-4044) proximal ulna (~106 mm) (Chiappe, 1996)
(PVL 4049) carpometacarpus (Walker, 1981)
(PVL-4056) radius (117.8 mm) (Chiappe, 1996)
(PVL-4060) proximal femur (~53 mm) (Chiappe and Calvo, 1994)
(PVL-4273) proximal femur (~60 mm) (Chiappe and Calvo, 1994)
(PVL-4180) proximal humerus (Chiappe, 1996)
(PVL-4265) proximal humerus (Walker and Dyke, 2009)
(PVL-4269) (Chiappe, 1996)
(PVL-4691) (Chiappe, 1996)
(PVL-4693) (Chiappe, 1996)
(PVL-4694) (Chiappe, 1996)
(PVL-4695) (Chiappe, 1996)
(PVL-4696) (Chiappe, 1996)
(PVL-4697) (Chiappe, 1996)
(PVL-4698) posterior mandible (Chiappe, 1996)
(PVL-4703) (Chiappe, 1996)
Comments- A large amount of mostly disarticulated enantiornithine specimens
have been found in the Lecho Formation. Most have been described and illustrated
by Walker and Dyke (2009), though some have only appeared as specimen numbers
in Chiappe (1996). Seven humeral morphologies are known from the site (Enantiornis
leali, E? sp. nov., Martinavis? vincei, M? saltariensis, M? minor, M? whetstonei
and Elbretornis), and three tarsometatarsal morphologies (Lectavis,
Yungavolucris and Soroavisaurus). These specimens probably belong
to those taxa, though determining their exact allocation is difficult. Several
specimens (PVL-4030-4032, 4034, 4036-4038, 4044, 4049, 4056, 4060 and 4273)
were referred to Martinavis sp. by Walker and Dyke, though none of the
Lecho species are here thought to belong to that genus. Still, these specimens
are too small to be Enantiornis or Elbretornis, and several (e.g.
PVL-4030, 4036, 4060) are so small they probably belong to minor or whetstonei.
PVL-4049 was originally illustrated by Walker (1981) then referred to Enantiornis
by Chiappe and Walker (2002). Walker and Dyke (2009) placed it in Martinavis
instead, as it is much smaller than Enantiornis.
PVL-4036 was photographed by Chiappe (1996), PVL-4037 was illustrated by Walker
(1981) and Chiappe and Walker (2002), and PVL-4038 was first noted by Chiappe
and Calvo (1994) and photographed in Chiappe (1996; as PVL-4048). Walker et
al. (2007) stated PVL-4037 is consistant in size with both Enantiornis
and Martinavis? vincei from the same locality, and Walker and Dyke (2009)
referred all three specimens to Martinavis sp..
The proximal end of PVL-4060 was illustrated schematically by Chiappe and Calvo
(1994), and based on its small size thought to belong to Martinavis? minor
or M? whetstonei by Walker and Dyke (2009).
PVL-4273 was illustrated by Chinsamy et al. (1995) and its histology was examined.
Chiappe and Walker (2002) referred PVL-4030 to Soroavisaurus and illustrated
it. Walker and Dyke (2009) reassigned the tibiotarsus to Martinavis sp.,
though they mislabeled it PVL-4031 in their materials list.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Enantiornithes (Aves)
from the Upper Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology.
14, 230–246.
Chinsamy, Chiappe and Dodson, 1995. Mesozoic avian bone microstructure: Physiological
implications. Paleobiology. 21(4), 561-574.
Chiappe, 1996. Late Cretaceous birds of southern South America: anatomy and
systematics of Enantiornithes and Patagopteryx deferrariisi. Munchner
Geowissenschaftliche Abhandlungen (A). 30, 203-244.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
unnamed Enantiornithes (
Moyano-Paz, Rozadilla, Agnolin, Vera, Coronel, Varela, Gomez-Dacal,
Aranciaga-Rolando, D'Angelo, Perez-Loinaze, Richiano, Chimento, Motta,
Sterli, Manabe, Tsuihiji, Isasi, Poire and Novas, 2022)
Late Campanian-Early Maastrichtian, Late Cretaceous
Chorrillo Formation, Santa Cruz, Argentina
Material- (MPM-PV-22866) distal pedal phalanx
(MPM-PV-22867) incomplete pedal ungual ?I
(MPM-PV-22868) incomplete pedal ungual
Comments- MPM-PV-22866-22868
were discovered in March 2020 and referred to Enantiornithes by
Moyano-Paz et al. (2022) based on "having poorly developed flexor
tubercles, a ventral "V" shaped groove delimiting the flexor tubercle
and dorsoventrally high and subrectangular-shaped proximal articular
surface."
Reference- Moyano-Paz, Rozadilla, Agnolin, Vera, Coronel, Varela, Gomez-Dacal,
Aranciaga-Rolando, D'Angelo, Perez-Loinaze, Richiano, Chimento, Motta,
Sterli, Manabe, Tsuihiji, Isasi, Poire and Novas, 2022. The uppermost
Cretaceous continental deposits at the southern end of Patagonia, the
Chorrillo Formation case study (Austral-Magallanes Basin):
Sedimentology, fossil content and regional implications. Cretaceous
Research. 130, 105059.
unnamed enantiornithine (Alvarenga and Nava, 2005)
Turonian-Santonian, Late Cretaceous
Adamantina Formation of the Bauru Group, Brazil
Material- (MZ coll.) vertebrae, ribs
References- Alvarenga, and Nava, 2005. Aves Enantiornithes do Cretaceo
Superior da Formacao Adamantina do Estado de Sao Paulo, Brasil. II Congresso
Latino-Americano de Paleontologia de Vertebrados (Rio de Janeiro), Boletim de
Resumos. 20.
Candeiro, Martinelli, Avilla and Rich, 2006. Tetrapods from the Upper Cretaceous
(Turonian-Maastrichtian) Bauru Group of Brazil: A reappraisal. Cretaceous Research.
27(6), 923-946.
unnamed enantiornithine (Candeiro, Agnolin, Martinelli and Buckup, 2012)
Maastrichtian, Late Cretaceous
Serra da Galga Formation of the Bauru Group, Brazil
Material- (CPP 482) incomplete metatarsal III
Comments- In 2021 the Serra da
Galga and Ponte Alta Members of the Marilia Formation were recognized
as the Serra da Galga Formation.
Reference- Candeiro, Agnolin, Martinelli and Buckup, 2012. First bird
remains from the Upper Cretaceous of the Peir�polis site, Minas Gerais
state, Brazil. Geodiversitas. 34(3), 617-624.
unnamed Enantiornithes (Close, Vickers-Rich, Trusler, Chiappe, O'Connor,
Rich, Kool and Komarower, 2009)
Aptian, Early Cretaceous
Wonthoggi Formation of the Strzelecki Group, Victoria, Australia
Material- (P 208183) partial furcula (Close, Vickers-Rich, Trusler, Chiappe,
O'Connor, Rich, Kool and Komarower, 2009)
incomplete tibiotarsus (Close and Vickers-Rich, 2009)
References- Close and Vickers-Rich, 2009. Australia's Mesozoic birds:
New material from the Early Cretaceous of Victoria. Journal of Vertebrate Paleontology.
29(3), 80A.
Close, Vickers-Rich, Trusler, Chiappe, O'Connor, Rich, Kool and Komarower, 2009.
Earliest Gondwanan bird from the Cretaceous of Southeastern Australia. Journal
of Vertebrate Paleontology. 29(2), 616-619.
Brevirostruavis Li, Wang, Stidham, Zhou and Clarke, 2022
= "Brevirostruavis" Li, Wang, Stidham, Zhou and Clarke, 2021 online
B. macrohyoideus Li, Wang, Stidham, Zhou and Clarke, 2022
= "Brevirostruavis macrohyoideus" Li, Wang, Stidham, Zhou and Clarke, 2021 online
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Material- (IVPP V13266) skull
(40.40 mm), mandibles, hyoids (28.4, 25.0 mm), atlantal neural arch,
axis, axial ribs, eight cervical vertebrae, four posterior dorsal
vertebrae, dorsal ribs, gastralia, synsacrum, five caudal vertebrae,
pygostyle (19.8 mm), proximal scapula, coracoids (~22.3 mm), furcula,
sternum (25.3 mm), sternal ribs, incomplete humeri (39.2 mm),
incomplete radii, incomplete ulnae (38.6 mm), scaptholunare, pisiforms,
carpometacarpi (mcI 2.9, 2.6; mcII 14.9, 15.0; mcIII 15.8, 17.7 mm),
phalanges I-1 (6.6, 6.9 mm), manual unguals I (3.5 mm), phalanges II-1
(8.8, 9.6 mm), phalanges II-2 (5.5, 6.3 mm), manual unguals II (3.3
mm), phalanges III-1 (4.6, 4.6 mm), manual claw sheaths, ilium, pubes,
ischia, femora (28.3 mm), tibiotarsi (40.0 mm), fibulae (~29.3 mm),
metatarsals I (5.1 mm), phalanges I-1 (5.3 mm), pedal unguals I (8.3
mm), tarsometatarsi (one incomplete; mtII 18.8, mtIII 20.4, mtIV 18.7
mm), phalanges II-1 (5.0 mm), phalanges II-2 (6.2 mm), pedal unguals II
(7.7 mm), phalanges III-1 (6.8 mm), phalanges III-2 (5.3 mm), phalanges
III-3 (5.9 mm), pedal unguals III (8.4 mm), phalanges IV-1 (2.6 mm),
phalanges IV-2 (3.1 mm), phalanges III-3 (3.4 mm), phalanges IV-4 (4.3
mm), pedal unguals IV (6.8 mm), pedal claw sheaths, body feathers,
remiges
Diagnosis- (after Li et al.,
2021 online) short and pointed rostrum lined with small peg-shaped
teeth; extremely long ceratobranchials, 63-71% of skull length; axial
postzygapophyseal facet tear-drop shaped; third cervical vertebra with
sub-rounded postzygapophyseal facet; elongate anterior cervical
prezygapophyses; well-extended anterolateral sternal processes;
posterolateral sternal processes with expanded triangular distal ends;
ischium with pronounced proximodorsal process; distal tibiotarsus with
knob on its anterior surface; fibula ~70% of tibiotarsal length (73%);
pedal digit I more robust than other pedal digits; tarsometatarsus ~50%
of tibiotarsal length (51%); medial rim of metatarsal III trochlea
larger than lateral rim.
Comments- Li et al. (2021
online) named and described this taxon, but the paper has no mention of
ZooBank so according to ICZN Article 8.5.3 (an electronic work
must "be registered in the Official Register of Zoological Nomenclature
(ZooBank) (see Article 78.2.4) and contain evidence in the work itself
that such registration has occurred"), "Brevirostruavis macrohyoideus"
Li et al.,
2021 was a nomen nudum that became valid in April 2022 when the
physical volume was published.
Li et al. (2022) added it to O'Connor's bird analysis and found
it resolves at the base of Enantiornithes in a polytomy with other
enantiornithines- Cruralispennia, Eoenantiornis, Eocathayornis, Protopteryx, Pterygornis, pengornithids, longipterygids, bohaiornithids and a derived clade including avisaurids.
Reference- Li, Wang, Stidham,
Zhou and Clarke, 2022 (online 2021). Novel evolution of a hyper-elongated
tongue in a Cretaceous enantiornithine from China and the evolution of
the hyolingual apparatus and feeding in birds. Journal of Anatomy.
Early View. 240(4), 627-638.
Cruralispennia Wang, O'Connor, Pan and Zhou, 2017
C. multidonta Wang, O'Connor, Pan and Zhou, 2017
Late Hauterivian, Early Cretaceous
Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Holotype- (IVPP V21711) (<1 year old subadult) partial
skull, dentary surangular, several cervical vertebrae, five
dorsal vertebrae, dorsal ribs, gastralia, partial synsacrum(?), two
caudal vertebrae, pygostyle (5.58 mm), scapulae, coracoids (12.37 mm),
sternum, sternal ribs, humeri (19.35 mm), radii (21.35 mm), ulnae
(22.48 mm), partial ilium, pubis (18.12 mm), ischium (6.82 mm), femur
(19.75 mm), tibiotarsus (23.08 mm), fibula, tarsometatarsus (19.71 mm),
nine pedal phalanges (?), four pedal unguals (?), body feathers, remiges
Diagnosis- (after Wang et al.,
2017) 14 dentary teeth; abbreviated, plough-shaped pygostyle with a
pygostyle/tarsometatarsus length ratio of about 0.28; coracoid
mediolaterally narrow with the
sternal margin measuring only one quarter of the proximodistal length;
sternum bearing a V-shaped posterior margin and subequal posteromedial
and posterolateral processes; postacetabular process of ilium short and
strongly ventrally directed; proximodorsal process of ischium
distally placed; pubis without distal expansion.
Other diagnoses- Wang et al. (2017) listed manus shorter than humerus as diagnostic, but the hands appear to be faked (see below).
Comments- This specimen was
discovered before August 2016. Note the labels for the pubic and
ischial peduncles in supp. fig. 1b are reversed. The pedal
phalanges appear to be partially fake, with e.g. the right pes
illustrated by the authors (supp. fig. 2) as having at least 16
non-ungual phalanges and five unguals when it should have ten and four
respectively. In this pes, the supposedly articulated toes and
pedal ungual I don't seem to consist of real bone, while five phalanges
and three unguals are real but may have been displaced or even added
from another fossil. In the less clearly photographed left pes,
14 non-ungual phalanges are illustrated of which four seem to be
genuine. This calls into question the veracity of other portions
of the holotype, such as the hands which each appear poorly defined
with differing metacarpal II lengths and a more robust first digit than
expected in an ornithothoracine. Most of the left hindlimb may
similarly be artificial or at least heavily reconstructed. The
identity of the large masses by the supposed proximal left femur is
uncertain, but may indeed be at least partially synsacral pieces as
labeled in figure 1b.
Wang et al. addded Cruralispennia to O'Connor's avialn matrix and recovered it sister to bohaiornithids.
Reference- Wang, O'Connor, Pan
and Zhou, 2017. A bizarre Early Cretaceous enantiornithine bird with
unique crural feathers and an ornithuromorph plough-shaped pygostyle.
Nature Communications. 8:14141.
Eopengornis Wang, O'Connor,
Zheng, Wang, Hu and Zhou, 2014
= "Eopengornis" Zheng, O'Connor, Wang, Wang, Zhang and Zhou, 2014
E. martini Wang, O'Connor, Zheng, Wang, Hu and Zhou, 2014
Late Hauterivian, Early Cretaceous
Luozigou, Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Holotype- (STM24-1) (subadult) skull, sclerotic plates, mandibles (one
partial), six cervical vertebrae, cervical ribs, several dorsal vertebrae, dorsal
ribs, gastralia, sacral vertebrae, seven caudal vertebrae, pygostyle, scapulae
(one partial), coracoids, furcula, sternum, posterolateral sternal processes,
three to six sternal ribs, humeri (38 mm), radii (one incomplete, one partial),
incomplete ulnae (42.4 mm), scapholunare, pisiforms, semilunate carpals, metacarpals
I, phalanges I-1, manual unguals I, metacarpals II, phalanges II-1, phalanges
II-2, manual unguals II, fragmentary metacarpals III, phalanges III-1, phalanges
III-2, pubes, femora (one incomplete, one partial; 27 mm), tibiae (31 mm), fibulae
(one partial), proximal tarsals, metatarsals I (6.9 mm), phalanges I-1 (7.8
mm), pedal unguals, metatarsals II (15.9 mm), phalanges II-1, phalanges II-2,
pedal unguals II, metatarsals III, phalanges III-1, phalanges III-2, phalanges
III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges
III-3, phalanges IV-4, pedal unguals IV, metatarsals V, remiges, retrices (~123
mm), body feathers
Diagnosis- (after Wang et al., 2014) accessory foramina piercing nasal
absent; numerous, small, occlusally tapered and slightly recurved teeth in upper
and lower jaws; fibula ends in rounded expansion; elongate hallux with metatarsal
I and phalanx I-1 each almost half length of metatarsal II.
Comments- The name "Eopengornis" was first published by Zheng
et al. (2014), which was online on September 8th and in print on September 23rd.
While a few basic details were given along with photos, the paper was clearly
meant to be published after Wang et al.'s (2014) official description which
appeared on October 17th. The absence of a species name (ICZN Article 13.3),
listed holotype (Article 16.4) and explicit statement about it being a new genus
(Article 16.1) means this early occurance of the genus name is a nomen nudum.
The holotype was purchased from a collector.
Wang et al. (2014) found this was sister to Pengornis in a version of
O'Connor's bird analysis that excluded all non-Jehol enantiornithines.
References- Wang, O'Connor, Zheng, Wang, Hu and Zhou, 2014. Insights
into the evolution of rachis dominated tail feathers from a new basal enantiornithine
(Aves: Ornithothoraces). Biological Journal of the Linnean Society. 113, 805-819.
Zheng, O'Connor, Wang, Wang, Zhang and Zhou, 2014. On the absence of sternal
elements in Anchiornis (Paraves) and Sapeornis (Aves) and the
complex early evolution of the avian sternum. Proceedings of the National Academy
of Sciences. 111(38), 13900-13905.
Explorornis Panteleyev, 1998
Diagnosis- (after Panteleyev, 1998) coracoid shaft primitively not narrower
than deep (also in Elsornis, walkeri and Catenoleimus).
(proposed) crest along the dorsolateral edge of the shaft (also in Eocathayornis).
Other diagnoses- Panteleyev (1998) also listed the broad distal expansion
in his diagnosis, but this is primitive for ornithothoracines. The low coracoid
tubercle is not different from Incolornis, Otogornis or Neuquenornis.
The gradually rising edge of the dorsal coracoid fossa is also present in walkeri,
Incolornis, Elsornis, Shanweiniao, Cathayornis and Eocathayornis.
The coracoid glenoid facet is generally rather flat in enantiornithines, and
is eroded in Explorornis nessovi, so Panteleev's characterization
of a convex glenoid in the taxon seems questionable.
Comments- Panteleyev also referred another species to this genus- E.
walkeri. While walkeri shares the plesiomorphic dorsoventrally flattened
coracoid shaft and shallow dorsal fossa of nessovi, there are no shared
derived characters yet identified that could unite the species. O'Connor (2009)
declared all Bissekty enantiornithines based on coracoids to be nomina dubia,
though without detailed comparison.
E. nessovi Panteleyev, 1998
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 4819) (~165 mm) distally incomplete coracoid (18.8 mm)
Diagnosis- (proposed) compared to E. sp. nov., lateral and medial
edges around dorsal coracoid fossa thin; coracoid shaft thinner; lateral edge
of coracoid completely concave.
Comments- This was collected in 1991 and originally identified as Enantiornithes
by Nessov and Panteleev (1993) and Nessov (1997). Panteleyev (1998) and it and
referred it to Alexornithidae within Alexornithiformes without comment. Nessov
(1996) referred the then unnamed specimen to Alexornithidae based on the narrow
shaft, shallow dorsal coracoid fossa and "slightly projected lateral margin".
Yet Nessov's classification is flawed, as for instance his enantiornithid Enantiornis
has a narrower shaft and less projected lateral margin than Explorornis,
while his concornithids such as Iberomesornis and Cathayornis
are comparable in these regards, and the latter also has a shallow dorsal fossa.
The coracoid fossa does indicate this is an enantiornithine, as Apsaravis
differs in having a concave scapular facet. Within Enantiornithes, the concave
lateral edge and shallow dorsal fossa may mean this is a relatively basal taxon.
References- Nessov and Panteleev, 1993. On the similarity of the Late
Cretaceous ornithofauna of South America and Central Asia. Trudy Zoologicheskogo
Instituta, RAN. 252, 84-94.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Nessov, 1997. [Cretaceous nonmarine vertebrates of northern Eurasia]. Saint
Petersburg, Institute of Earth Crust. 1-218.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
E. sp. nov. (Panteleyev, 1998)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (ZIN PO 4818) (~165 mm) incomplete coracoid (~19 mm)
Diagnosis- (proposed) compared to E. nessovi, lateral and medial
edges around dorsal coracoid fossa thick; coracoid shaft thicker; lateral; edge
of coracoid distally convex.
Comments- This was originally identified as Enantiornithes by Nessov
and Panteleev (1993) and Nessov (1997). It was described as Explorornis
sp. 1 by Panteleyev (1998), which seems valid since it has the apomorphic crest
of that genus. However, the other shared character (shaft broader than deep)
is plesiomorphic and the slightly convex laterodistal edge might indicate it
is more derived. Kurochkin (1996) referred it to Alexornithiformes fam. indet.
without justification.
References- Nessov and Panteleev, 1993. On the similarity of the Late
Cretaceous ornithofauna of South America and Central Asia. Trudy Zoologicheskogo
Instituta, RAN. 252, 84-94.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Nessov, 1997. [Cretaceous nonmarine vertebrates of northern Eurasia]. Saint
Petersburg, Institute of Earth Crust. 1-218.
Panteleyev, 1998. New species of enantiornithines (Aves:
Enantiornithes) from Upper Cretaceous of central Kyzylkum. Russian
Journal of Ornithology. Express-issue 35, 3-15.
Mirusavis Wang, O'Connor, Bailleul and Li, 2020
= "Mirusavis" Wang, O'Connor, Bailleul and Li, 2019 online
M. parvus Wang, O'Connor, Bailleul and Li, 2020
= "Mirusavis parvus" Wang, O'Connor, Bailleul and Li, 2019 online
Early Albian, Early Cretaceous
Sihedang, Jiufotang Formation, Liaoning, China
Holotype- (IVPP V18692) (~16 g; subadult female) axis, third to tenth cervical
vertebrae, six dorsal ribs, two uncinate processes, gastralia, scapulae
(one incomplete), coracoids (one partial; 16.30 mm), furcula, partial
sternum, several sternal ribs, humerus (30.02 mm), radius (~29.87 mm),
ulna (31.71 mm), scapholunare, metacarpal I (2.56 mm), phalanx I-1 (4.85
mm), manual ungual I (1.45 mm), carpometacarpus (13.21 mm), phalanx
II-1 (7.43 mm), phalanx II-2 (4.38 mm), proximal manual ungual II,
phalanx III-1 (3.36 mm), femur (27.33 mm), proximal tibiotarsus,
proximal fibula
Diagnosis- (Wang, O'Connor, Bailleul and Li, 2020) sternum with anterolateral processes (also in Shangyang and Concornis);
elongated posteromedial process of sternum posterolaterally directed;
proximodistally short humeral deltopectoral crest; distal margin of
humerus strongly angled ventrodistally; ulna with well-developed
bicipital tubercle; ulna with distinct olecranon process; dorsal cotyle
of ulna convex; radius with bicipital tubercle; interosseous surface of
radius smooth; manual ungual II larger than manual ungual I.
Comments- This specimen was
discovered prior to August 2019. It was first published as
unnamed enantiornithine IVPP V18692 in Wang et al.'s (2020a)
phylogenetic analysis, added to O'Connor's avialan analysis. The
paper describing it was
published online on December 19 2019 but does not contain reference to
a
ZooBank registration, so the name was a nomen nudum (ICZN Article
8.5.3. states names published electronically must "be registered in the
Official Register of Zoological Nomenclature (ZooBank) (see Article
78.2.4) and contain evidence in the work itself that such registration
has occurred") until the volume was physically released in June 2020.
Wang et al. (2020b) used Mirusavis to O'Connor's avialan analysis and recovered it sister to Shangyang in Enantiornithes more derived than pengornithids, Protopteryx and Monoenenatiornis.
References- Wang, O'Connor,
Bailleul and Li, 2020a (online 2019). Evolution and distribution of medullary bone:
Evidence from a new Early Cretaceous enantiornithine bird. National
Science Review. 7(6), 1068-1078.
Wang, O'Connor, Zhou and Zhou, 2020b (online 2019). New toothed Early
Cretaceous ornithuromorph bird reveals intraclade diversity in pattern
of tooth loss. Journal of Systematic Palaeontology. 18(8), 631-645.
Noguerornis Lacasa-Ruiz, 1989
N. gonzalezi Lacasa-Ruiz, 1989
Late Berriasian-Early Barremian, Early Cretaceous
La Pedrera de Rubies Lithographic Limestones, Spain
Holotype- (LP.1702) last dorsal vertebra (1.6 mm), three dorsal rib fragments,
first sacral vertebra (2 mm), second sacral vertebra (2.4 mm), incomplete furcula,
humeri (22.8 mm), radii (23.1, 23.2 mm), ulna (24.3 mm), scapholunare, pisiform, carpometacarpus,
proximal phalanx I-1, ischium, partial tibia, long bone shaft, coverts, secondary
remiges
Diagnosis- ischial symphysis present.
References- Lacasa-Ruiz, 1986. Nota preliminar sobre el hallazgo de restos
keos de un ave fosil en el yacimiento neocomiense del Montsec. (Prov .Lerida,
Espafia). Ilerdu. 47, 203-206.
Lacasa-Ruiz, 1989. An Early Cretaceous fossil bird from Montsec Mountain (Lleida,
Spain). Terra Nova. 1(1), 45-46.
Lacasa-Ruiz, 1989. Nuevo genero de ave fosil del yacimiento Neocomiense del
Montsec (Provincia de Lerida, Espana). Estudios Geologicos. 45, 417-425.
Chiappe and Lacasa-Ruiz, 2002. Noguerornis gonzalezi (Aves: Ornithothoraces)
from the Early Cretaceous of Spain. 230-239. in Chiappe and Witmer, (eds.).
Mesozoic Birds: Above the Heads of Dinosaurs. University of California Press,
Berkeley, Los Angeles, London.
Orienantius Liu, Chiappe, Zhang, Serrano and Meng, 2019
= "Orienantius" Liu, Chiappe, Zhang, Serrano and Meng, 2018
O. ritteri Liu, Chiappe, Zhang, Serrano and Meng, 2019
= "Orienantius ritteri" Liu, Chiappe, Zhang, Serrano and Meng, 2018
Late Hauterivian, Early Cretaceous
Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Holotype- (BMNHC Ph 1156a/b) (juvenile) skull, mandibles,
hyoids, seven to eight cervical vertebrae, eleven dorsal vertebrae,
dorsal ribs, synsacrum, six caudal vertebrae, pygostyle (14.6 mm),
scapulae, coracoids (~13.5 mm), furcula, sternum, sternal ribs, humeri
(29.2 mm), radii (27.2 mm), ulnae (29.4 mm), scapholunare, pisiform,
semilunate carpals, metacarpal I (2.2 mm), phalanges I-1 (5.1 mm),
manual unguals I (3.1 mm), metacarpals II (12.9 mm), phalanges II-1
(7.7 mm), phalanges II-2 (5.1 mm), manual unguals II (3.1 mm),
metacarpals III (13.7 mm), phalanges III-1 (3.8 mm), phalanges III-2
(0.8 mm), manual claw sheaths, ilia, pubes (20.3 mm), ischium, femora
(25.1 mm), (tibiotarsus 31.1 mm) tibiae, astragalacalcanea, distal
tarsals III, metatarsals I, phalanges I-1 (4.3 mm), pedal unguals I
(6.1 mm), metatarsals II, phalanges II-1 (4.1 mm), phalanges II-2 (5.2
mm), pedal unguals II (6.8 mm), metatarsals III (17.3 mm), phalanges
III-1 (5.5 mm), phalanges III-2 (4.5 mm), phalanges III-3 (4.8 mm),
pedal unguals III (6.0 mm), metatarsals IV, phalanges IV-1 (2.9 mm),
phalanges IV-2 (2.6 mm), phalanges III-3 (2.3 mm), phalanges IV-4 (3.0
mm), pedal unguals IV (5.4 mm), pedal claw sheaths, body feathers,
remiges, retrices, skin
Paratype- (BMNHC Ph 1154a/b)
(juvenile) posterior skull, posterior mandible, cervical series, dorsal
series, dorsal ribs, gastralia, synsacrum, free caudal series,
pygostyle (14.9 mm), coracoids (13.3 mm), sternum, sternal ribs, humeri
(28.5 mm),
radii (29.5 mm), ulnae (29.8 mm), scapholunares, pisiforms, semilunate
carpals, metacarpals I (2.4 mm),
phalanges I-1 (4.9 mm), manual unguals I (2.5 mm), metacarpals II (~13
mm), phalanges II-1 (7.5 mm),
phalanges II-2 (5.1 mm), manual unguals II (2.1 mm), metacarpals III
(~14 mm), phalanges III-1 (4.1 mm), phalanx III-2 (~0.7 mm), pubis (~18
mm), ischium, femora (24.2 mm),
(tibiotarsus 31.9 mm) tibiae (one partial), metatarsals I, phalanges
I-1 (4.2 mm), pedal unguals I (5.4 mm), metatarsals II, phalanges II-1
(4.0 mm), phalanges II-2 (4.8 mm),
pedal unguals II (6.2 mm), metatarsals III (17.4 mm), phalanges III-1
(5.3 mm), phalanges III-2 (4.5 mm),
phalanges III-3 (4.5 mm), pedal unguals III (6.1 mm), metatarsals IV,
phalanges IV-1 (3.0 mm),
phalanges IV-2 (~1.8 mm), phalanges III-3 (2.4 mm), phalanges IV-4 (3.2
mm), pedal unguals IV (4.9 mm),
pedal claw sheaths, body feathers, remiges, retrices, skin
Diagnosis- (after Liu et al.,
2019) posterior end of dentary with a weak fork; reduced number of
maxillary and dentary teeth (not many more than 3 in the maxilla and 6
in the dentary); ventral median groove on synsacral vertebrae; long and
narrow pygostyle (>80% the length of the tarsometatarsus); furcula
with very long hypocleidium (>80% length of furcular rami); sternum
with slightly deflected posterolateral processes ending in triangular
distal expansions, short posteromedial processes, and a narrow
posteromedian process that projects posteriorly beyond the level of the
posterolateral processes; semilunate carpal with distal projection
overlapping metacarpal III; short manual digit I (digit I/metacarpal II
length ratio 0.39); gently expanded pubic boot.
Comments- The specimens were discovered before March 2018. The description of Orienantius was first released online as an Accepted Manuscript on October 25 2018, but this did not contain reference to a
ZooBank registration, so the name was a nomen nudum (ICZN Article
8.5.3. states names published electronically must "be registered in the
Official Register of Zoological Nomenclature (ZooBank) (see Article
78.2.4) and contain evidence in the work itself that such registration
has occurred") until the volume was physically released in March 2019.
Liu et al. did not add Orienantius to a phylogetic analysis, but proposed it was more similar to Jehol enantiornithines than Protopteryx and pengornithids.
Reference- Liu, Chiappe, Zhang,
Serrano and Meng, 2019 (online 2018). Soft tissue preservation in two
new enantiornithine specimens (Aves) from the Lower Cretaceous
Huajiying Formation of Hebei Province, China. Cretaceous Research. 95,
191-207.
Pengornis Zhou, Clarke and Zhang,
2008
= Parapengornis Hu, O'Connor and Zhou, 2015a
= "Chiappeavis" O'Connor, Wang, Zheng, Hu, Zhang and Zhou, 2015 online
= Chiappeavis O'Connor, Wang, Zheng, Hu, Zhang and Zhou, 2016
= Yuanchuavis Wang, O'Connor, Zhao, Pan, Zheng, Wang and Zhou, 2021
P. houi Zhou, Clarke and Zhang, 2008
= Parapengornis eurycaudatus Hu, O'Connor and Zhou, 2015a
= "Chiappeavis magnapremaxillo" O'Connor, Wang, Zheng, Hu, Zhang
and Zhou, 2015 online
= Chiappeavis magnapremaxillo O'Connor, Wang, Zheng, Hu, Zhang
and Zhou, 2016
= Yuanchuavis kompsosoura Wang, O'Connor, Zhao, Pan, Zheng, Wang and Zhou, 2021
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V15336) (440 g) skull (~54.7 mm), mandibles, eleven cervical
vertebrae, few dorsal vertebrae, dorsal ribs, gastralia, synsacrum (~27.1 mm),
six caudal vertebrae, proximal pygostyle, scapulae, coracoids (37.9 mm), incomplete
furcula, humeri (64.3 mm), radii (66.7 mm), ulnae (70.7 mm), scapholunares, pisiforms,
carpometacarpi (34.3 mm; mcII 27 mm, mcIII 31.1 mm), phalanges II-1 (16.3 mm),
phalanx II-2, phalanx III-1, manual ungual, ilium, partial pubes (~49.2 mm),
femora (48 mm), tibiotarsi (50.4 mm), fibula (~44.5 mm), metatarsal I (8.7 mm),
pedal ungual I, tarsometatarsi (26.5 mm), phalanx II-1 (5.9 mm), phalanx II-2
(8.1 mm), pedal ungual II (12.4 mm), phalanx III-1 (8.6 mm), phalanx III-2 (7.9
mm), phalanx III-3 (8.8 mm), pedal ungual III (11.7 mm), phalanx IV-1 (5.2 mm),
phalanx IV-2 (~3.8 mm), phalanx IV-3 (4.1 mm), phalanx IV-4 (5.9 mm), pedal
ungual IV (9.9 mm), ungual
Referred- (IVPP V18632) (subadult) skull (39.7 mm), sclerotic ossicles,
mandibles, seven cervical vertebrae, two anterior dorsal vertebrae, four posterior
dorsal vertebrae, dorsal ribs, uncinate processes, gastralia, eight sacral vertebrae
(sacrum 22.1 mm), eight caudal vertebrae (series 15.3 mm), pygostyle (9.2 mm),
partial scapulae (34.9 mm), partial coracoids, incomplete furcula, sternum (22.8
mm), sternal ribs, humeri (one incomplete; 45.7 mm), radii (45.5 mm), ulnae
(49 mm), scapholunare, pisiform, semilunate carpal, metacarpals I (4.2 mm), phalanx
I-1 (10.7 mm), manual ungual I (5.5 mm), metacarpals II (one partial; 20.1 mm),
phalanges II-1 (one partial; 12.5 mm), phalanges II-2 (8.8 mm), manual unguals
II (4.5 mm), metacarpals III (19.7 mm), phalanges III-1 (one partial; 6.3 mm),
phalanx III-2 (1 mm), incomplete ilia, pubes (one incomplete; 38.4 mm), ischia
(one partial), femora (34.8 mm), tibiae (37.7 mm), fibulae (26.5 mm), astragali,
calcanea, metatarsal I (6.6 mm), phalanx I-1 (5.8 mm), pedal ungual I (8.2 mm),
metatarsal II (19.1 mm), phalanx II-2 (6.1 mm), pedal ungual II (7 mm), metatarsal
III (19.7 mm), phalanx III-1 (6.8 mm), phalanx III-2 (6 mm), phalanx III-3 (6.4
mm), pedal ungual III (5.2 mm), partial metatarsal IV, phalanx IV-1 (3.8 mm),
phalanx IV-2 (3.1 mm), phalanx IV-3 (2.8 mm), phalanx IV-4 (4.4 mm), pedal ungual
IV (6.5 mm), metatarsal V(?), pedal claw sheaths, remiges, retrix (Hu, Zhou
and O'Connor, 2014)
(IVPP V18687; holotype of Parapengornis eurycaudatus) (<1 year old
juvenile) skull (39.9 mm), mandibles, hyoids, axis, third cervical vertebra,
fourth cervical vertebra, fifth cervical vertebra, sixth cervical vertebra,
seventh cervical vertebra, eighth cervical vertebra, ninth cervical vertebra,
first dorsal vertebra, second dorsal vertebra, third dorsal vertebra, five mid-posterior
dorsal vertebrae, dorsal ribs, several uncinate processes, gastralia, synsacrum,
seven or eight caudal vertebrae, pygostyle (8.4 mm), scapulae (one incomplete;
46.3 mm), coracoids (26.3 mm), furcula, incomplete sternum, at least eight sternal
ribs, humeri (52.1 mm), radii (53.7 mm), ulnae (54.9 mm), scapholunare, pisiform, semilunate
carpal, metacarpal I (5.3 mm), phalanx I-1 (11.4 mm), manual ungual I (6.7 mm),
metacarpal II (24.8 mm), phalanges II-1 (12.7 mm), phalanges II-2 (9.2 mm),
manual unguals II (4.8 mm), metacarpal III (27.4 mm), phalanges III-1 (8.1 mm),
phalanx III-2 (1.2 mm), ilia, pubes (37.2 mm), ischia, femora (39.8 mm), tibiae
(40.4 mm), fibulae (34.6 mm), astragali, calcaneum, proximal tarsal, metatarsals
I (one incomplete; 8.6 mm), phalanges I-1 (one incomplete; 9.2 mm), pedal unguals
I (one incomplete; 7.4 mm), metatarsals II (one incomplete; ~19.5 mm), phalanges
II-1 (5.2 mm), phalanges II-2 (one partial; 7 mm), pedal unguals II (one partial;
8.2 mm), metatarsals III (one incomplete; ~20.5 mm), phalanges III-1 (6.6 mm),
phalanges III-2 (one fragmentary; 6.3 mm), phalanges III-3 (6.4 mm), pedal unguals
III (one incomplete; 8.2 mm), metatarsals IV (one incomplete; 19.1 mm), phalanges
IV-1 (one fragmentary; 4.8 mm), phalanges IV-2 (one fragmentary; 2.7 mm), phalanges
IV-3 (3.2 mm), phalanges IV-4 (4.5 mm), pedal unguals IV (one partial; 5.8 mm),
pedal claw sheaths, metatarsals V, body feathers, retrices, remiges (144.2 mm)
(Hu, O'Connor and Zhou, 2015a)
(IVPP V27883; holotype of Yuanchuavis kompsosoura) skull,
sclerotic plates, mandibles, atlas, axis, third-tenth cervical
vertebrae, first-tenth dorsal vertebrae, several partial cervical ribs,
few uncinate processes, synsacrum, first-seventh caudal vertebrae,
pygostyle (18 mm), two chevrons, ilia (34.62 mm), pubes (46.81 mm),
ischia (31.78 mm), femora (one incomplete; 45.37 mm), tibiotarsi (one
incomplete; 50.79 mm), fibulae, metatarsals I (one distal; 10.42 mm),
phalanges I-1 (11.32 mm), partial pedal ungual I, metatarsals II (25.03
mm), distal phalanx II-1, phalanges II-2 (one proximal; 10.19 mm),
pedal ungual II (6.72 mm), metatarsals III (~27.07 mm), phalanx III-1
(8.64 mm), phalanges III-2 (one distal; 7.73 mm), phalanx III-3 (8.54
mm), metatarsals IV (26.21 mm), phalanx IV-1 (5.0 mm), phalanges IV-2
(3.97 mm), proximal phalanges IV-3, metatarsals V (6.52 mm), body
feathers, retrices (Wang, O'Connor, Zhao, Pan, Zheng, Wang and Zhou,
2021 online)
(STM 29-11; holotype of Chiappeavis magnapremaxillo)
(juvenile) skull, sclerotic plates, mandible, several cervical
vertebrae, six dorsal vertebrae, dorsal ribs, synsacrum. caudal
vertebrae, pygostyle (~18 mm), chevron, incomplete scapulae, coracoids,
furcula, sternum, sternal ribs, humeri, radii, ulnae, scapholunare,
pisiform, carpometacarpi, fragmentary phalanx II-1, distal phlannx
II-2, manual ungual II, phalanges III-1, ilia (one incomplete), pubes,
femora (~42 mm), tibiae, astragalocalcanea, phalanx I-1, pedal unguals
I, metatarsals II, metatarsals III (~21 mm), metatarsals IV, numerous
pedal phalanges, five pedal unguals, pedal claw sheaths, remiges,
retrices (56-74 mm) (O'Connor, Sullivan, Zhou and Zheng, 2015;
described by O'Connor, Wang, Zheng, Hu, Zhang and Zhou, 2015)
?(STM 29-15) (juvenile) dorsal vertebrae, dorsal ribs, gastralia, synsacrum,
caudal fragments, pygostyle (8.7 mm), scapulae (one incomplete, one proximal;
26 mm), incomplete coracoids, sterna, sternal ribs, humeri (48.2 mm), partial
radii, ulnae (one incomplete, one partial), scapholunare, pisiform, semilunate carpal,
metacarpal I, phalanges I-1 (11.5 mm), manual ungual I (5.8 mm), metacarpals
II (one incomplete; 25.6 mm), phalanges II-1 (12.4 mm), phalanges II-2 (7.9
mm), manual unguals II (3.9 mm), metacarpals III (one partial; 27.6 mm), phalanx
III-1 (6.9 mm), ilia, pubes, ischia, femora (37.2 mm), tibiae (39.5 mm), fibula,
astragalocalcanea, distal tarsal, metatarsals I (8.5 mm), phalanges I-1 (8.7
mm), pedal unguals I, metatarsals II (18.5 mm), phalanx II-1, phalanx II-2,
pedal ungual II, metatarsals III, phalanx III-1, phalanx III-2, phalanx III-3,
pedal ungual III, metatarsals IV, phalanx IV-?, pedal ungual IV, remiges (O'Connor
et al., 2015)
Early Albian, Early Cretaceous
Chifeng, Jiufotang Formation, Inner Mongolia, China
?(IVPP V15576) (subadult female) femur (38.8 mm), incomplete
tibiotarsus, partial fibula, metatarsal I 8.4 mm), fragmentary phalanx
I-1, fragmentary pedal ungual I, tarsometatarsus (21.9 mm), phalanx
II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2,
phalanx III-3, pedal ungual III, phalanx IV-1, pahalnx IV-2, phalanx
IV-3, pahalnx IV-4, pedal ungual IV, pedal claw sheaths, metatarsal V,
body feathers (O'Connor, Erickson, Norell, Bailleul, Hu and Zhou, 2018)
Diagnosis- (after Zhou et al., 2008) premaxillae unfused; hooked scapular
acromion; globose humeral head that projects further proximally than the deltopectoral
crest.
(after Hu et al., 2014) 9-13 dentary teeth that are small, stout, and unrecurved.
Comments- Hu et al. (2014) described the new specimen IVPP V18632 which
they considered a subadult individual of a new species of Pengornis.
The differences they viewed as non-ontogenetic (nasal process of maxilla more
delicate; dorsal process of maxilla pointed rather than rodlike [not comparable
states]; furcula more slender with interclavicular angle of 75 degrees rather
than 65 [ontogenetic?]; humeral head flat rather than globose [not apparent];
deltopectoral crest weaker and narrower [ontogenetic?]; pubis straight [in anterior
view in IVPP V18687?]) seem to be minor and comparable to those I consider individual
variation in other paravian species, so I refer IVPP V18632 to P. houi.
Note too that the interclavicular angle and humeral head convexity is intermediate
in IVPP V18687.
O'Connor et al. (2015a) described a skeleton lacking the skull and neck (STM
29-15) as Pengornithidae indet., with unspecified differences "in pedal
morphology and inferred adult body size" suggesting it was not conspecific
with IVPP V18632. As STM 29-15 is from the Jiufotang Formation (O'Connor pers.
comm., 2015), it is here tentatively assigned to the only pengornithid from
that formation that I recognize, Pengornis itself.
O'Connor et al. (2018) describe a hindlimb with medullary bone as
Pengornithidae indet., but given this is from the Jiufotang Formation
it is here tentaively referred to Pengornis.
Parapengornis- Hu et al. (2015a) described a new genus of pengornithid, Parapengornis eurycaudatus
based on basically complete specimen IVPP V18687. Note the supposed quadratojugal
is almost certainly a postorbital, while the supposed palatines are likely postdentary
mandibular elements. They suggested several diagnostic characters and referred
IVPP V18632 to the taxon. Of their diagnostic characters, the teeth of all birds
are basally constricted, and those of Parapengornis are not more numerous
than Pengornis (9 vs.13 in the dentary). The width of the pygostyle,
lateral expansion of the distal processes and and concavity of the posterior
margin cannot be evaluated in the laterally preserved element of Pengornis.
The furculae of all enantiornithines are Y-shaped, and that of Parapengornis
is not noticably more slender or straighter than Pengornis. Hu et al.
stated "pedal phalanx I-1 is longer than metatarsal I and approximately
half the length of metatarsal III", but I-1 seems to be unpreserved in
Pengornis. The more slender and recurved teeth could be ontogenetic (as
in the Eichstatt Archaeopteryx vs. the London specimen), as could the
less elongated anterior cervical vertebrae (as in many living birds). Contra
the text, the maxillary fenestra doesn't seem to be larger or more anteriorly
positioned than in Pengornis, nor does the femoral head seem less developed.
The quadrate was said to differ from Pengornis in being straight posteriorly,
but the shape difference is due to it being in anterior instead of lateral view.
The lower deltopectoral crest is potentially ontogenetic as in IVPP V18632.
Stated proportional differences (coracoid length/width ratio 192% vs. 202%;
ulnohumeral ratio 105% vs. 108%) are easily explainable by individual variation.
This leaves the following as potentially supporting Parapengornis' validity-
shorter posterodorsal lacrimal process; pygostyle shorter than half the length
of metatarsal III (41% vs. >73%); metatarsal I >40% of metatarsal II length.
IVPP V18632 cannot be shown to have more recurved and slender teeth, as the
apices are flat (taphonomic), its elongated anterior cervicals (contra Hu et
al.) and short metatarsal I are like Pengornis. It does resemble Parapengornis'
type in having a short posterodorsal lacrimal process and pygostyle shorter
than half metatarsal III's length (47%). Given the intermediate characters of
IVPP V18632, it's viewed as most probable the three specimens are conspecific.
Chiappeavis- O'Connor et al. (2016) described another new genus of pengornithid, Chiappeavis
magnapremaxillo,
based on almost complete specimen STM 29-11. Note the electronic
version was published on December 31, 2015 and did not mention ZooBank,
and the paper version was not published until January 11, 2016.
Thus ICZN Article 8.5.3 (a work must "be
registered in the Official Register of Zoological Nomenclature
(ZooBank) (see Article 78.2.4) and contain evidence in the work itself
that such registration has occurred") made "Chiappeavis
magnapremaxillo" O'Connor et al. 2015 a nomen nudum until 2016.
Several characters were listed as supposedly diagnostic here as well.
The premaxilla was said to have a larger body and convex ventral
margin, but the convex element has far too long of a ventral margin to
be a premaxilla, so is more likely an incomplete maxilla with the base
of the ascending process. The actual right premaxilla is then just the
small anterodorsal portion right below the partially preserved left
premaxilla, and has no visible ventral margin. The posterodorsal
premaxillary process was claimed to be longer than other pengornithids,
almost reaching the frontals. Yet this bone is highly abraded just
posterior to figure 2A's 'l pm' label, so that this posterior portion
could easily belong to the right nasal instead. This is bolstered by
the fact it's the same width as the left nasal and that the right nasal
is otherwise missing. The synsacrum has eight vertebrae (as in IVPP
V18632), while the authors claim Pengornis' holotype has
seven. Yet the description of the latter says only that seven are visible, but
that the anterior end is covered, and indeed there could easily be another one
beneath the ilium. STM 29-15 only has seven but is obviously younger based on
its unfused sterna. The "median trabeculae" [sic = posteromedian process]
of Chiappeavis is said to have diagnostic concave lateral margins, but
this is also true in IVPP V18632 (though not STM 29-15) and is unpreserved in
Parapengornis, while Pengornis' holotype doesn't preserve the
sternum. The posteromedian angle of the sternum is said to be narrow, but while
its 53 degree angle is a bit less than IVPP V18632's (at 68) or STM 29-15's
(at 66), Parapengornis' holotype could have an identical angle if complete,
and again Pengornis' holotype doesn't preserve the element. Finally,
the authors claim the proximal articular surface of the tibia is laterodistally
inclined, but this is only true of the left tibia, with the right tibia having
a right angle between the surface and the long axis of the bone. Furthermore,
Pengornis' holotype and IVPP V18632 both have inclined surfaces, though
Parapengornis' holotype lacks them. Given the variation in Chiappeavis'
holotype, the variation is likely due to perspective or taphonomy. Besides the
characters listed in the diagnosis, O'Connor et al. note the short anterior
cervicals are like the Parapengornis holotype but unlike Pengornis'
holotype. As the latter is larger than the others, this may support ontogenetic
cervical elongation. They also correctly note the long pygostyle is like Pengornis'
holotype, but unlike IVPP V18632 or Parapengornis' holotype. Finally,
the short metatarsal I is said to be like Pengornis' holotype, and is
additionally like IVPP V18632 but unlike Parapengornis' holotype or STM
29-15. Thus the only real difference from Pengornis' holotype is the
shorter anterior cervicals, and while there are a few differences from other
pengornithid specimens (laterally concave posteromedian sternal process unlike
STM 29-15; narrower posterior sternal angle than STM 29-15 and IVPP V18632;
long pygostyle unlike STM 29-15, IVPP V18632 and Parapengornis' type;
short metatarsal I unlike STM 29-15 and Parapengornis' type), there's
no pattern of character distribution that would suggest separate pengornithid
species (e.g. Parapengornis shares the cervical length and probably sternal
angle, while IVPP V18632 is different in cervical length but shares metatarsal
I length). Thus all Jiufotang pengornithids are still retained in Pengornis
houi.
Yuanchuavis-
Wang et al. (2021) described a supposed new taxon of
pengornithid- Yuanchuavis kompsosoura
based on IVPP V27883, a
skeleton missing pectoral girdles and forelimbs. Regarding its
validity, the premaxilla is said to have five teeth but the medial view
of the right premaxilla in figure S1B shows the last tooth is upside
down so that the root protrudes ventrally as if it's a crown tip in
lateral view, and so is probably a dentary tooth.
Similarly, the same figure shows the edentulous tip of the bone is
exaggerated by the first tooth being displaced and artificially angled
posteriorly. The actual edentulous portion is only two FABLs
long, similar to Pengornis, IVPP V18632 and Parapengornis
(right premaxilla; first tooth displaced and loose in left
element). The supposedly short anterior and posterior lacrimal
processes are similar to Parapengornis, IVPP V18632 and Pengornis
except that the posterior process of the latter is longer as
interpreted by O'Connor. The large hypapophyses on dorsals one
and two are difficult to evaluate in other Pengornis
as anterior dorsals are usually disarticulated and oriented at odd
angles when exposed at all. Contra the authors, the dorsoventral
depth of the dorsal central fossae (e.g. D5) are similar to IVPP
V18632, Parapengornis and Chiappeavis. Finally, the short anterodorsal pygostyle processes are also present in Parapengornis and Chiappeavis (eroded in Pengornis), while the elongate anteroventral process is also present in Parapengornis, partly exposed in Pengornis and probably hidden under caudal vertebrae in Chiappeavis. Of the variable characters noted above for Parapengornis and Chaippeavis,
the pygostyle/metatarsus ratio is intermediate (66%), metatarsal I is
42% the length of metatarsal II, and anterior cervicals are elongate,
again showing no pattern and no distinct separated groups of
ratios. Thus like other Jiufotang pengornithids, Yuanchuavis is
synonymized with Pengornis here.
Relationships- Zhou et al. (2008) found Pengornis to be more derived than Protopteryx,
but outside a clade containing Concornis, Gobipteryx, Neuquenornis
and Cathayornis when entered into Clarke's matrix. Hu et al. (2014) entered
the holotype and their new specimen into O'Connor's matrix and found them to
be the most basal non-Protopteryx, non-longipterygid enantiornithines.
This is the same result as found in the more extensive analysis of Wang et al.
(2014), where it is mislabeled IVPP V18631. Hu et al. (2015) added the Parapengornis
specimen and three characters, and found pengornithids to be more deeply nested
in Enantiornithes than before, though the authors doubted this was true.
References- Zhou, Clarke and Zhang, 2008. Insight into diversity, body
size and morphological evolution from the largest Early Cretaceous enantiornithine
bird. Journal of Anatomy. 212, 565-577.
Hu, Zhou and O'Connor, 2014. A subadult specimen of Pengornis and character
evolution in Enantiornithes. Vertebrata PalAsiatica. 52(1), 77-97.
Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine family
(Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Hu, O'Connor and Zhou, 2015a. A new species of Pengornithidae (Aves: Enantiornithes)
from the Lower Cretaceous of China suggests a specialized scansorial habitat
previously unknown in early birds. PLoS ONE. 10(6), e0126791.
Hu, O'Connor and Zhou, 2015b. A new species of Pengornithidae (Aves: Enantiornithes)
from the Lower Cretaceous of China suggests a specialized scansorial habitat
previously unknown in early birds. Journal of Vertebrate Paleontology. Program
and Abstracts 2015, 147.
O'Connor, Sullivan, Zhou and Zheng, 2015b. Evolution and functional significance
of derived sternal ossification patterns in ornithothoracine birds. Journal
of Vertebrate Paleontology. Program and Abstracts 2015, 189.
O'Connor, Zheng, Sullivan, Chuong, Wang, Li, Wang, Zhang and Zhou, 2015a. Evolution
and functional significance of derived sternal ossification patterns in ornithothoracine
birds. Journal of Evolutionary Biology. 28(8), 1550-1567.
O'Connor, Wang, Zheng, Hu, Zhang and Zhou, 2016 (online 2015). An enantiornithine with a
fan-shaped tail, and the evolution of the rectricial complex in early birds.
Current Biology. 26(1), 114-119.
O'Connor, Erickson, Norell, Bailleul, Hu and Zhou, 2018. Medullary bone
in an Early Cretaceous enantiornithine bird and discussion regarding
its identification in fossils. Nature Communications. 9:5169.
Wang, O'Connor, Zhao, Pan, Zheng, Wang and Zhou, 2021. An Early
Cretaceous enantiornithine bird with a pintail. Current Biology. 31, 1-8.
Protopterygiformes Zhang and Zhou, 2006
Protopterygidae Zhang and Zhou, 2006
Protopteryx Zhang and Zhou,
2000
P. fengningensis Zhang and Zhou, 2000
Late Hauterivian, Early Cretaceous
Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Holotype- (IVPP V11665) (~130 mm; 70 g, juvenile?) skull (28.3 mm), mandible,
seven or eight cervical vertebrae (18.5), twelve dorsal vertebrae (33.9 mm),
dorsal ribs, sacrum, seven free caudal vertebrae (9.4 mm), pygostyle (11.3 mm),
scapulae (21.7 mm), coracoids, furcula (14.7 mm), sternum, humeri (~26 mm),
radii, ulnae, semilunate carpal, distal carpal III, metacarpal I, phalanx I-1,
manual ungual I, metacarpal II, phalanx II-1, phalanx II-2, manual ungual II,
metacarpal III, phalanx III-1, phalanx III-2, ilium (15.3 mm), pubis (22.3 mm),
ischium (12.9 mm), femur (19 mm), tibia, fibula, astragalus, calcaneum, distal
tarsal, tarsometatarsus, pedal phalanges, pedal unguals, feather impressions
Paratype- (IVPP V11844) (~130 mm; juvenile?) incomplete skeleton including
skull, mandible, seven or eight cervical vertebrae (19.1), twelve dorsal vertebrae
(34 mm), dorsal ribs, seven free caudal vertebrae, pygostyle, coracoids (12.7
mm), furcula (14 mm), sternum (15.9 mm), sternal ribs, forelimbs, ilium (14.8
mm), feather impressions
Diagnosis- (proposed) scapulocoracoid articulation flat; procoracoid
process; wide interclavicular angle (ontogenetic?); carpometacarpus unfused
(ontogenetic?); distal tarsals unfused to tarsometatarsus (ontogenetic?).
Comments- Jin et al. (2008) reidentified the horizon of Protopteryx
as the Huajiying Formation, instead of the Yixian Formation as stated
by Zhang and Zhou (2000) or the Dabeigou Formation as in Zhang et al.
(2008). Wang et al. (2017) lists the holotype's pygostyle and
tarsometatarsus lengths as 21.32 and 30.90 mm respectively, but these
are clearly far too large.
References- Zhang and Zhou, 2000. A primitive enantiornithine bird and
the origin of feathers. Science. 290, 1955-1959.
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx
and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science
Bulletin. 53(18), 2820-2827.
Zhang, Zhou and Benton, 2008. A primitive confuciusornithid bird from China
and its implications for early avian flight. Science in China Series D: Earth
Sciences. 51(5), 625-639.
Wang, O'Connor, Pan and Zhou, 2017. A bizarre Early Cretaceous
enantiornithine bird with unique crural feathers and an ornithuromorph
plough-shaped pygostyle. Nature Communications. 8:14141.
Shangyang Wang and Zhou 2019
S. graciles Wang and Zhou, 2019
Early Albian, Early Cretaceous
Mutouchengzi, Jiufotang Formation, Liaoning, China
Holotype- (IVPP V25033) (adult)
skull, mandibles, atlas, axis, third cervical vertebra, fourth cervical
vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh
cervical vertebra, eighth cervical vertebra, ninth cervical vertebra,
tenth cervical vertebra, eleventh cervical vertebra, twelfth cervical
vertebra, first dorsal vertebra, four posterior dorsal vertebrae,
dorsal ribs, uncinate processes, gastralia, synsacrum (17.2 mm), six
caudal vertebrae, pygostyle (13.9 mm), scapulae (~23.6 mm), coracoids
(16.6, 16.7 mm), furcula, sternum, sternal ribs, humeri (28.4, ~28 mm),
radii (28.9, 28.6 mm), ulnae (30.5, ~30.2 mm), scapholunares, pisiforms,
carpometacarpi (mcI 2.4 mm; 14.0 mm), phalanges I-1 (4.9, 5.0 mm),
manual unguals I (2.0, ~1.7 mm), phalanges II-1 (one distal; ~7.7 mm),
phalanges II-2 (one distal; 5.1 mm), manual ungual II (1.5 mm), phalanx
III-1 (4.2 mm), ilia (17.5 mm), pubes (22.6 mm), ischium, femora (25.5
mm), tibiotarsi (31.0, 31.2 mm), fibulae, metatarsals I, phalanges I-1
(4.2, 4.1 mm), pedal unguals I (3.9, 3.8 mm), tarsometatarsi (17.2 mm),
phalanges II-1 (3.8, 3.8 mm), phalanges II-2 (5.0, 4.8 mm), pedal
unguals II (3.9, 3.6 mm), phalanges III-1 (5.5, 5.6 mm), phalanges
III-2 (4.9, 4.9 mm), phalanges III-3 (5.2, 5.1 mm), pedal unguals III
(4.5, 4.1 mm), phalanges IV-1 (3.0 mm), phalanges IV-2 (2.7, 2.8 mm),
phalanges III-3 (3.1, 3.0 mm), phalanges IV-4 (4.2, 3.9 mm), pedal
unguals IV (3.2, 3.3 mm), pedal claw sheaths
Diagnosis- (after Wang and Zhou, 2019) fully fused premaxillae (also in Gobipteryx); eleven cervical vertebrae; eight fused sacrals; hypocleidium very short; sternum with anterolateral processes (also in Pterygornis, Piscivorenantiornis, Cathayornis and Rapaxavis); coracoid slender; pubis sigmoid in lateral view; metatarsal II wider than metatarsal III; pedal digit II shorter than IV.
Comments- This was discovered prior to May 2018.
Wang and Zhou added Shangyang to O'Connor's avialan analysis and recovered it sister to Eocathayornis plus Longipterygidae.
Reference- Wang and Zhou 2019.
A new enantiornithine (Aves: Ornithothoraces) with completely fused
premaxillae from the Early Cretaceous of China. Journal of Systematic
Palaeontology. 17(15), 1299-1312.
unnamed clade
= Longipterygidae sensu O'Connor et al. 2009
Definition- (Longipteryx chaoyangensis + Longirostravis hani)
Alexornithiformes Brodkorb, 1976
Definition- (Alexornis antecedens <- Coracias garrulus, Picus viridis,
Gobipteryx minuta) (Martyniuk, 2012)
Alexornithidae Brodkorb, 1976
References- Brodkorb, 1976. Discovery of a Creteceous bird, apparently ancestral
to the orders Coraciiformes and Piciformes (Aves: Carinatae). in Olson (ed.).
Collected papers in avian phylogeny honoring the 90th birthday of Alaxander
Wetmore. Smithsonian Contributions to Paleobiology. 27, 67-73.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Alexornis Brodkorb, 1976
A. antecedens Brodkorb, 1976
Campanian, Late Cretaceous
Bocana Roja Formation, Mexico
Holotype- (LACM 33213 in part) distal humerus (~105 mm)
Paratype- ....(LACM 33213 in part) distal humerus
Referred- ....(LACM 32213 in part) proximal scapula, proximal coracoid
(~12 mm), proximal ulna, distal femur, proximal tibia, >20 fragments (Brodkorb,
1976)
Diagnosis- anterior cnemial crest present.
Reference- Brodkorb, 1976. Discovery of a Creteceous bird, apparently
ancestral to the orders Coraciiformes and Piciformes (Aves: Carinatae). In Olson
(ed.). Collected Papers in Avian Phylogeny Honoring the 90th Birthday of Alaxander
Wetmore. Smithsonian Contributions to Paleobiology. 27, 67-73.
Cratoavis Carvalho, Novas, Agnol�n,
Isasi, Freitas and Andrade, 2015b
C. cearensis Carvalho, Novas, Agnol�n, Isasi, Freitas and
Andrade, 2015b
Late Aptian, Early Cretaceous
Nova Olinda Member of the Crato Formation, Brazil
Holotype- (UFRJ-DG 031 Av) (~60 mm, juvenile) incomplete skull, sclerotic
ossicles, partial mandible, five cervical vertebrae, six dorsal vertebrae, several
partial dorsal ribs, (caudal series 8.3 mm) eight partial to complete caudal
vertebrae, pygostyle (9.4 mm), scapula, coracoids (7.7 mm), few sternal ribs,
humeri (14 mm), radii, ulnae (13.3 mm), phalanx I-1, carpometacarpi (one fragmentary;
7.2 mm), metacarpal I fragment?, phalanx II-1, phalanx II-2, manual ungual II,
partial phalanx III-1 (3.2 mm), fragmentary ilia, incomplete pubes, femora (12.8,
~11.7 mm), tibiotarsi (~12 mm), metatarsals I, phalanges I-1 (2.6 mm), pedal
unguals I (3.5 mm), metatarsals II (one partial), phalanges II-1 (one fragmentary),
partial pedal unguals II, metatarsals III (one partial; 8.9 mm), phalanges III-1
(one partial), phalanx III-2, phalanges III-3 (one incomplete), pedal unguals
III, metatarsal IV, phalanges IV-1, phalanges IV-2, phalanx IV-3, phalanges
IV-4 (one partial), incomplete pedal unguals IV, pedal claw sheaths, body feathers,
remiges, retrices (79.9 mm)
Diagnosis- (after Carvalho et al., 2015b) maxillary teeth; dorsal vertebrae
with fan-shaped and very well-developed neural spines; caudal neural spines
transversely thick; strongly concave medial margin of coracoid; proximally rounded
humeral head; tibiotarsus shorter than femur and subequal in length to metatarsals;
very elongate pedal digit III phalanges; very long rectrices, much longer than
total body size.
Comments- Carvalho et al. (2015a) described UFRJ-DG 031 Av as Euenantiornithes
indet., finding it to be more derived than Protopteryx and Elsornis.
It was diagnosed and named by Carvalho et al. (2015b) in a paper with identical
authorship submitted five weeks after the original was accepted, and approved
a week before the original was published.
References- Carvalho, Novas, Agnolin, Isasi, Freitas and Andrade, 2015a.
A Mesozoic bird from Gondwana preserving feathers. Nature Communications. 6,
7141.
Carvalho, Novas, Agnol�n, Isasi, Freitas and Andrade, 2015b. A new genus
and species of enantiornithine bird from the Early Cretaceous of Brazil. Brazilian
Journal of Geology. 45(2), 161-171.
Grabauornis Dalsatt, Ericson
and Zhou, 2014
= "Grabauornis" Dalsatt, 2012
G. lingyuanensis Dalsatt, Ericson and Zhou, 2014
= "Grabauornis lingyuanensis" Dalsatt, 2012
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V14595) (235 mm adult) partial skull (32.2 mm), mandibles
(one partial; 15.2 mm), nine to ten cervical vertebrae, seven dorsal vertebrae,
partial dorsal ribs, gastralia, synsacrum, four caudal vertebrae, pygostyle
(14.8 mm), incomplete scapulae (24.2, 26.3 mm), incomplete coracoids (20.1,
20 mm), partial furcula (11.5 mm), sternum, sternal ribs, incomplete humeri
(33.5 mm), radii (one incomplete, one fragmentary; 31.7 mm), incomplete ulna
(35.2 mm), scapholunare, carpometacarpus (4.6, 17.5, 16.6 mm), phalanx I-1 (7.3 mm),
proximal manual ungual I, phalanx II-1 (6.4 mm), phalanx II-2 (6.2 mm), manual
ungual II (2.1 mm), ilia, femora (31.3 mm), tibiotarsi (one partial; 36.2 mm),
fibula, metatarsals I (4.1, 4.2 mm), phalanges I-1 (5, 5 mm), pedal unguals
I (7.6, 7.2 mm), tarsometatarsi (II 18.6, 18.4; III 19.7, 19.4 mm; IV 18.3,
18.3 mm), phalanges II-1 (4.7, 4.2 mm), phalanges II-2 (6.8, 6.4 mm), pedal
unguals II (6.2, 4.5 mm), phalanges III-1 (6.5, 7 mm), phalanges III-2 (5.3,
4.6 mm), phalanx III-3 (5.2 mm), pedal ungual III (6.5 mm), phalanges IV-4 (3.2
mm), phalanx IV-2 (3.8 mm), phalanx IV-3 (2.8 mm), phalanx IV-4 (3.7 mm), body
feathers, remiges
Diagnosis- (after Dalsatt et al., 2014) small teeth; well developed acrocoracoid
process; long posterolateral steranl process and very short posteromedial sternal
process; posterolateral process expanded distally; metacarpals II and III nearly
equal in width with almost no intermetacarpal space; humerus with prominent
head and much shorter than ulna.
Comments- This taxon was initially announced in a thesis (Dalsatt, 2012)
then described in a rather poorly translated paper (Dalsatt et al., 2014), and
found to be an enantiornithine more derived than Protopteryx and Pengornis
using a version of Clarke's bird analysis.
Reference- Dals�tt, 2012. Fossil birds: Contributions to the understanding
of avian evolution. PhD thesis. Stockholm University. 35 pp.
Dalsatt, Ericson and Zhou, 2014. A new Enantiornithes (Aves) from the Early
Cretaceous of China. Acta Geologica Sinica (English Edition). 88(4), 1034-1040.
Halimornis Chiappe, Lamb and
Ericson, 2002
H. thompsoni Chiappe, Lamb and Ericson, 2002
Early-Middle Campanian, Late Cretaceous
Mooreville Chalk Formation, Alabama, US
Holotype- (D2K 035) two dorsal vertebrae, caudal vertebra, pygostyle,
proximal humerus, distal femur
....(UAMNH PV996.1.1) dorsal centrum, dorsal neural arch, proximal scapula
Reference- Chiappe, Lamb and Ericson, 2002. New enantiornithine bird
from the marine Upper Cretaceous of Alabama. Journal of Vertebrate Paleontology.
22(1), 170-174.
Kizylkumavis Nesov, 1984a
K. cretacea Nesov, 1984a
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (TsNIGRI 51/11915) (~110 mm) distal humerus (~27 mm)
Comments- O'Connor (2009) proposed Kizylkumavis is a nomen dubium
as it is indistinguishable from Alexornis. The latter seems true except
for the slightly narrower ectocondyle in Kizylkumavis, though more detailed
comparison to other enantiornithines is necessary.
References- Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Sazavis Nessov vide Nessov and Jarkov,
1989
S. prisca Nessov vide Nessov and Jarkov, 1989
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Holotype- (ZIN PO 3472) (~185 mm) distal tibiotarsus (4.5 mm wide)
Other diagnoses- Nessov and Jarkov (1989) initially included characters
now known to be more widespread in enantiornithines. They said the retinaculum
tuberosity is poorly developed and distally placed, but there are two tuberosities,
the weaker of which is proximally placed as in e.g. Gobipteryx, Nanantius
and Qiliania. The distal tuberosity is actually more prominent than the
former two, though comparable and plesiomorphic in any case. The distal transverse
width (222% of minimal shaft width) is not greater than e.g. Nanantius
or ?Soroavisaurus PVL-4033. The medial condyle (misidentified as lateral
by the authors) is less broad than e.g. Gobipteryx or PVL-4033. The medial
condyle also has a rounded proximal margin in e.g. Gobipteryx, Qiliania
and PVL-4033.
Kurochkin (1996) listed a few new characters to distinguish Sazavis from
Gobipteryx (as his new taxon Nanantius valifanovi). Of these,
the supposedly more abrupt transition from tibiotarsal shaft to condyles isn't
different from e.g. Qiliania or PVL-4033. The medial condyle is more
circular in these two specimens as well. Finally, the intercondylar fossa is
more medially placed in e.g. Qiliania and Nanantius, and is symplesiomorphic.
Comments- Nessov and Jarkov (1989) initially assigned Sazavis
to ?Alexornithidae within Enantiornithes, but mistook the medial condyle for
the lateral and vice versa. O'Connor (2009) declared Sazavis a nomen
dubium because she misunderstood "the distinguishing characteristic of
the specimen" as being "the transverse paracondylar expansion"
as opposed to being "only medially expanded in Gobipteryx."
She correctly noted the former morphology is also present in the then unnamed
Qiliania. Yet this was not a character mentioned by Nessov and Jarkov
in their initial diagnosis nor one mentioned by Kurochkin as differing from
Gobipteryx (his Nanantius valifanovi). Yet Sazavis differs
from Qiliania in having a less anteriorly projected lateral condyle,
a larger medial condyle (56% of distal width vs. 53%) especially visible as
its distal boundary, and more developed distal retinaculum tuberosity. Resolving
whether Sazavis is diagnostic compared to other enantiornithines requires
a more detailed comparison of tibiotarsi.
References- Nessov and Jarkov, 1989. New Cretaceous-Paleogene birds of
the USSR and some remarks on the origin and evolution of the class Aves. Proceedings
of the Zoological Institute, Leningrad. 197, 78-97.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut
Senckenberg. 181, 37-53.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Yatenavis Herrera, Agnolin, Rozadilla, Coco, Manabe, Tsuihiji and Novas, 2022 online
Y. ieujensis Herrera, Agnolin, Rozadilla, Coco, Manabe, Tsuihiji and Novas, 2022 online
Early Maastrichtian, Late Cretaceous
Estancia La Anita, Chorrillo Formation, Santa Cruz, Argentina
Holotype- (MPM-PV-23086) distal humerus (6.2 mm trans)
Diagnosis- (after Herrera et
al., 2023) humeral shaft narrow (less than half the maximum width of
the distal end of the humerus); humeral shaft slightly bowed
anteroposteriorly; dorsal supracondylar process prominent
and slightly concave (also in Alexornis, Kizylkumavis and Martinavis);
m. brachialis fossa wide, deep and proximally extended; m. brachialis
fossa medially positioned and laterally delimited by a ridge;
well-defined fossa proximal to distal condyles, and dorsally separated
from m. brachialis fossa through a wide and prominent ridge;
anteroposterior ridge along distal margin of ventral condyle (also in Alexornis, Kizylkumavis and Martinavis);
D-shaped distal fossa delimited laterally by ridge of ventral condyle
and separated from olecranal fossa; distal end of humerus almost
perpendicular to longitudinal axis of bone.
Comments- The holotype was
discovered in March 2022. Herrera et al. (2022) found "the latter
caudal ridge [on the ventral condyle distally] is perpendicular to the
cranial margin of the ventral condyle and together forms a L-shaped
prominence when viewed distally in Yatenavis, a trait shared with MPEF-PV 2359 and Martinavis vincei, but not with Kizylkumavis." Furthermore "Yatenavis
differs from the enantiornithines, excepting MPEF-PV 2359, in that the
site of origin for m. brachialis is positioned at the craniomedial
surface of the humerus."
Reference- Herrera, Agnolin,
Rozadilla, Coco, Manabe, Tsuihiji and Novas, 2023 (2022 online). New
enantiornithine bird from the uppermost Cretaceous (Maastrichtian) of
southern Patagonia, Argentina. Cretaceous Research. 144, 105452.
Boluochiformes Zhou and Zhang, 2006
Boluochidae Zhou and Zhang, 2006
Boluochia Zhou, 1995
B. zhengi Zhou, 1995
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V9770) (~155 mm) incomplete premaxilla, nasal fragments,
partial dentaries, teeth, dorsal rib fragments, incomplete sacrum, six caudal
vertebrae, pygostyle (21.5 mm), posterior sternum, three sternal ribs?, posterior
ilium (~7.5 mm), pubes (one fragmentary; 25.15 mm), ischia (17 mm), distal femora,
incomplete tibiotarsi (~37 mm), metatarsal I (4.1 mm), tarsometatarsi (17.4,
17.7 mm; II 17.2 mm, III 17.4 mm, IV 17.5 mm), at least seventeen pedal phalanges,
six pedal unguals
Diagnosis- (after O'Connor et al., 2011) premaxilla anterior to external
nares imperforate with parallel dorsal and ventral margins; dorsal surface of
premaxilla with slight concavity just anterior to the nasal processes; premaxilla
with large, recurved teeth; large and robust pygostyle 20% longer than tarsometatarsus;
metatarsals II–III subequal in length and ending distally at approximately
the same level; metatarsal IV longer than II and III and laterally deflected
along the distal fifth of the tarsometatarsus.
Comments- This specimen was found by Zhou in 1990 along with the holotype
of Cathayornis and an unidentified sternal impression (IVPP V 9941).
It is mostly preserved as a natural mold. O'Connor et al. (2011) redescribed
it, noting the supposedly curved toothless premaxilla was misinterpreted and
contains several teeth. In addition, the specimen is very similar to Longipteryx
and may be a senior synonym.
References- Zhou, 1995. Discovery of a new enantiornithine bird from
the Early Cretaceous of Liaoning, China. Vertebrata PalAsiatica. 33(2), 99-113.
Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park.
221 pp.
Zhou and Hou, 2002. The discovery and study of Mesozoic birds in China. In Chiappe
and Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University
of California Press. 160-183.
O'Connor, Zhou and Zhang, 2010. A new look at 'old' birds from the Jehol fauna.
Journal of Vertebrate Paleontology. Program and Abstracts 2010, 141A.
O'Connor, Zhou and Zhang, 2011. A reappraisal of Boluochia zhengi (Aves:
Enantiornithes) and a discussion of intraclade diversity in the Jehol avifauna,
China. Journal of Systematic Palaeontology. 9(1), 51-63.
Longipterygiformes Zhang, Zhou, Hou and Gu, 2001
Definition- (Longipteryx chaoyangensis <- Cathayornis yandica,
Iberomesornis romeralii, Enantiornis leali) (Martyniuk, 2012)
Longipterygidae Zhang, Zhou, Hou and Gu, 2001
Other definitions- (Longipteryx chaoyangensis + Longirostravis hani)
(O'Connor, Wang, Chiappe, Gao, Meng, Cheng and Liu, 2009)
Longipteryginae Zhang, Zhou, Hou and Gu, 2001 vide Stidham and O'Connor, 2021
Longipteryx Zhang, Zhou,
Hou and Gu, 2001
= "Camptodontus" Li, Gong, Zhang, Yang and Hou, 2010 (preoccupied
Dejean, 1826)
= Camptodontornis Demirjian, 2019
References- Dejean, 1826. Species general des coleopteres, de la collection
de M. le Comte Dejean. Tome second. Crevot, Paris. 501 pp.
Zhang, Zhou, Hou and Gu, 2001. Early diversification of birds: Evidence from
a new opposite bird. Chinese Science Bulletin. 46(11), 945-950.
Li, Gong, Zhang, Yang and Hou, 2010. A new enantiornithine bird from the Early
Cretaceous of Liaoning, China. Acta Palaeontologica Sinica. 49(4), 524-531.
Demirjian, 2019. Camptodontornis gen. nov., a replacement name for the bird genus Camptodontus Li, Gong, Zhang, Yang, and Hou, 2010, a junior homonym of Camptodontus Dejean, 1826. Zootaxa. 4612(3), 440.
Stidham and O'Connor, 2021. The evolutionary and functional implications of the unusual quadrate of Longipteryx chaoyangensis (Avialae: Enantiornithes) from the Cretaceous Jehol Biota of China. Journal of Anatomy. 239(5), 1066-1074.
L. chaoyangensis Zhang, Zhou, Hou and Gu, 2001
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V12325) (~190 mm, 190 g) skull (55.06 mm), mandible,
hyoids, seven cervical vertebrae, at least five dorsal vertebrae, sixteen dorsal
ribs, ten uncinate processes, six rows of gastralia, sacrum, six caudal vertebrae,
pygostyle (21.38 mm), scapulae, incomplete coracoids (19.86 mm), furcula, sternal
fragments, four sternal ribs, incomplete humeri (43.48, ~42.03 mm), incomplete
radii (~43.48 mm), incomplete ulnae (44.26, ~47.1 mm), scapholunare, pisiform, semilunate
carpal, metacarpal I (4.4 mm), phalanx I-1 (8.5 mm), manual ungual I (7.7 mm),
metacarpal II (17 mm), phalanx II-1 (10 mm), phalanx II-2 (9.3 mm), manual ungual
II (8.5 mm), metacarpal III (18 mm), phalanx III-1 (5.1 mm), phalanx III-2 (1.5
mm), ilia, incomplete pubes, incomplete ischium, incomplete femora (28.26, 28.77
mm), incomplete tibiae (30.07 mm), fibulae (12 mm), proximal tarsals, metatarsal
I (4.8 mm), phalanx I-1, pedal ungual I, tarsometatarsus (metatarsal II 20 mm;
III 20.5 mm; IV 21 mm), phalanx II-1, phalanx II-2, phalanx III-1, proximal
phalanx III-2, phalanges from digit IV, feather impressions
Paratypes- (IVPP V12552) (juvenile) (93% size of holotype) complete skeleton
including skull and sternum
(IVPP V12553) furcula, humerus
(IVPP V12554) ulna
Diagnosis- scapula distally broad; wide interclavicular angle (ontogenetic?);
metatarsal IV longer than III (also in Boluochia and Alethoalaornis).
References- Zhang, Zhou, Hou and Gu, 2001. Early diversification of birds:
Evidence from a new opposite bird. Chinese Science Bulletin. 46(11), 945-950.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD Thesis. University of Southern California. 586 pp.
L? yangi (Li, Gong,
Zhang, Yang and Hou, 2010) new combination
= "Camptodontus" yangi Li, Gong, Zhang, Yang and Hou, 2010
= Camptodontornis yangi (Li, Gong, Zhang, Yang and Hou, 2010) Demirjian, 2019
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (SG2005-B1) skull (56 mm), mandibles, four cervical vertebrae,
synsacrum, scapulae (one partial), coracoids (19 mm), furcula, sternum (18 mm),
humerus (42 mm), radius (42 mm), ulna (46 mm), partial pubis, fragments
Referred- (DNHM D2566) incomplete skeleton including incomplete skull
(O'Connor, 2009)
Barremian-Aptian, Early Cretaceous
Yixian Formation?, Liaoning, China
(DNHM D2889) (adult) skull (70 mm), mandibles, atlas, axis, five cervical vertebrae,
at least ten dorsal vertebrae, dorsal ribs, gastralia, synsacrum, at least five
caudal vertebrae, pygostyle, scapulae (one incomplete), coracoids (24 mm), furcula,
partial sternum, humeri (40 mm), radii (40 mm), ulnae (42 mm), pisiform, carpometacarpi
(mcI 5, mcII 17, mcIII 23 mm), phalanges I-1 (9 mm), manual unguals I (8 mm),
phalanges II-1 (12 mm), phalanges II-2 (11 mm), manual unguals II (7 mm), phalanges
III-1 (one fragmentary), partial pubis, ischium, femora (31 mm), tibiotarsi
(38 mm), fibula (~15 mm), metatarsal I, phalanx I-1 (7 mm), pedal ungual I (6
mm), tarsometatarsi (24 mm; one incomplete), phalanges II-1 (4 mm), phalanges
II-2 (6 mm), pedal unguals II (7 mm), phalanges III-1 (5 mm), phalanges III-2
(4 mm), phalanges III-3 (7 mm), pedal unguals III (7 mm), phalanges IV-1 (5
mm), phalanges IV-2 (4 mm), phalanges IV-3 (4 mm), phalanges IV-4 (6 mm), pedal
unguals IV (9 mm), pedal claw sheaths (O'Connor, 2009; described by Wang et
al., 2015)
Diagnosis- (after Li et al., 2010) skull three times longer than tall;
large conical premaxillary teeth; widely spaced premaxillary teeth; teeth strongly
recurved; frontal broad and flat; dentary long; dentary teeth similar to but
shorter than those of premaxilla; anterior cervical centra heterocoelous; posterior
sternal carina; posterolateral sternal process slender with slightly expanded
distal end; posteromedial sternal process short; ulnohumeral ratio ~110%; radius
about 75% as wide as ulna.
Comments- Li et al. (2020) assigned "Camptodontus" yangi
to Longipterygidae based on the "long and thick beak, similar sternum
and furcula", but it has not been included in a phylogenetic analysis.
They described it as a new genus of enantiornithine, but the name is
preoccupied by a carabid beetle named 184 years earlier (Martyniuk,
2012) so was replaced by Camptodontornis (Demirjian, 2019). Wang
et al. (2014) referred the holotype to Longipteryx based on the "large teeth strongly
curved caudally [and] lateral trabecula of sternum slightly laterally directed
with simple distal expansion", though they did not state whether the species
was valid or use the new combination Longipteryx yangi posited above.
Martyniuk proposed a possible synonymy with Boluochia based on tooth
size. The latter genus itself has been compared favorably to Longipteryx
by O'Connor, and the relationship between these specimens is presently uncertain.
This is seemingly the same taxon as DNHM D2889, a specimen called Longipteryx
sp. by O'Connor (O'Connor, 2009; O'Connor and Chiappe, 2011), both of which
have larger premaxillary teeth than the L. chaoyangensis holotype or
IVPP V12552. Wang et al. (2015) fully described it, referring it to Yuanjiawa
in the Yixian Formation, whereas O'Connor listed it as from the Jiufotang Formation
like other specimens with this morphology. Wang et al. referred DNHM D2889 to
Longipteryx chaoyangensis while noting some differences (forelimb/hindlimb
ratio 1.2 vs. 1.5; femorotibiotarsal ratio .8 vs. 1.0; femorohumeral ratio .8
vs. .6; clavicular arm / hypocleidium ratio 1.1 vs. .8), which they ascribed
to age.
O'Connor (2009) also referred DNHM D2566 to Longipteryx sp..
References- Dejean, 1826. Species general des coleopteres, de la collection
de M. le Comte Dejean. Tome second. Crevot, Paris. 501 pp.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD Thesis. University of Southern California. 586 pp.
Li, Gong, Zhang, Yang and Hou, 2010. A new enantiornithine bird from the Early
Cretaceous of Liaoning, China. Acta Palaeontologica Sinica. 49(4), 524-531.
O'Connor and Chiappe, 2011. A revision of enantiornithine (Aves: Ornithothoraces)
skull morphology. Journal of Systematic Palaeontology. 9(1), 135-157.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine family
(Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Wang, Zhao, Shen, Liu, Gao, Cheng and Zhang, 2015. New material of Longipteryx
(Aves: Enantiornithes) from the Lower Cretaceous Yixian Formation of China with
the first recognized avian tooth crenulations. Zootaxa. 3941(4), 565-578.
Demirjian, 2019. Camptodontornis gen. nov., a replacement name for the bird genus Camptodontus Li, Gong, Zhang, Yang, and Hou, 2010, a junior homonym of Camptodontus Dejean, 1826. Zootaxa. 4612(3), 440.
Yun, 2019. Comments on the taxonomic validity of Camptodontornis yangi (Li, Gong, Zhang, Yang, and Hou, 2010) and its relationships to Longipteryx chaoyangensis Zhang, Zhou, Hou, and Gu, 2000 and Boluochia zhengi Zhou, 1995. Zootaxa. 4652(2), 391-392.
Shengjingornis Li, Wang, Zhang
and Hou, 2012
S. yangi Li, Wang, Zhang and Hou, 2012
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype-
(PMOL AB00179) skull (~46.6 mm), mandibles, atlas, axis, seven cervical
vertebrae, seven dorsal vertebrae, dorsal ribs, gastralia, synsacrum,
four caudal vertebrae, pygostyle, scapulae, coracoids (18.7 mm),
furcula, sternum (31.6 mm), sternal ribs, humeri (41 mm), radii (43
mm), ulnae (42 mm), scapholunares, pisiform, metacarpals I (3.8 mm),
phalanges I-1 (8.8 mm), manual unguals I (5.1 mm), carpometacarpi (mcII
18.5, mcIII 22.8 mm), phalanx II-1, phalanx II-2 (8 mm), phalanx III-1
(8.8 mm), phalanx III-2 (5.1), ilia, pubes (29.4 mm), ischia, femora
(37.5 mm), tibiotarsi (44.1 mm), fibulae (21.2 mm), metatarsals I (4.4
mm), phalanges I-1 (4.1 mm), pedal unguals I (6.8 mm), tarsometatarsi
(mtII 21.1, mtIII 23.5, mtIV 22 mm), phalanges II-1 (5.3 mm), phalanges
II-2 (6.7 mm), pedal unguals II (7.6 mm), phalanges III-1 (7.1 mm),
phalanges III-2 (6.2 mm), phalanges III-3 (6.5 mm), pedal unguals III
(7.5 mm), phalanges IV-1 (3.8 mm), phalanx IV-2 (~3.1 mm), phalanges
IV-3 (3.3 mm), phalanges IV-4 (3.5 mm), pedal unguals IV (6.1 mm)
Diagnosis- (after Li et al., 2012) long, tapering, slightly curved beak;
teeth anteriorly; short nasal; slender jugal; high frontal; Y-shaped furcula
with distally expanded hypocleidium; short coracoids; low and posteriorly restricted
sternal keel; humerus nearly as long as radius and ulna; carpometacarpus fused;
at least two manual unguals; femoral head developed; fibula nearly half length
of tibiotarsus; metatarsus proximally fused.
Comments- Li et al. (2012) entered Shengjingornis into O'Connor's
matrix and found it to be sister to Longirostravis. Note most of the
supposed diagnostic characters are symplesiomorphies for enantiornithines.
Reference- Li, Wang, Zhang and Hou, 2012. A new enantiornithine bird
from the Lower Cretaceous Jiufotang Formation in Jinzhou area, Western Liaoning
Province, China. Acta Geologica Sinica. 86(5), 1039-1044.
Longirostravisiformes Zhou and Zhang, 2006
Longirostravisidae Zhou and Zhang, 2006
= Longirostrisavinae Zhou and Zhang, 2006 vide Stidham and O'Connor, 2021
Diagnosis- manual ungual I absent; manual ungual II absent; longitudinal
crest on the central portion of its pedal unguals' sides.
References-
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata
PalAsiatica. 44(1), 60-98.
Stidham and O'Connor, 2021. The evolutionary and functional implications of the unusual quadrate of Longipteryx chaoyangensis (Avialae: Enantiornithes) from the Cretaceous Jehol Biota of China. Journal of Anatomy. 239(5), 1066-1074.
Shanweiniao O'Connor, Wang,
Chiappe, Gao, Meng, Cheng and Liu, 2009
S. cooperorum O'Connor, Wang, Chiappe, Gao, Meng, Cheng and Liu,
2009
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (DMNH D1878) (adult) skull (31.36 mm), sclerotic ring, mandibles,
nine cervical vertebrae, six dorsal vertebrae, partial dorsal ribs, gastralia,
partial synsacrum, several caudal vertebrae, pygostyle (12.37 mm), scapula,
coracoids (~12.61 mm), furcula (~8.95 mm), sternum, sternal ribs, humeri (~21.31,
22.43 mm), radii (~22.53 mm), ulnae (~23.36 mm), partial proximal carpal, phalanx
I-1, manual ungual I, partial metacarpal II, phalanges II-1 (4.55 mm), phalanges
II-2 (2.62 mm), phalanx III-1 (2.33 mm), partial ilium, partial pubes, femora
(~17.6 mm), tibiotarsi (22.61, 22.41 mm), fibula, partial metatarsals I, phalanges
I-1 (3.71 mm), pedal unguals I, tarsometatarsi (11.9, 11.75 mm; mtII 9.3, 10.05
mm, mtIII 11.16, 20.84 mm, mtIV 10.98, 10.72 mm), phalanges II-1 (2.75 mm),
phalanges II-2 (4.4, 4.44 mm), pedal unguals II (6.51, 6.54 mm), phalanges III-1
(~2.71 mm), phalanges III-2 (2.98 mm), phalanges III-3 (~3.99 mm), pedal unguals
III (~5.67, 5.19 mm), phalanges IV-1 (1.82 mm), phalanges IV-2 (1.28 mm), phalanges
IV-3 (2.15 mm), phalanges IV-4 (3.23 mm), pedal unguals IV (~5.54, 5.8 mm),
pedal claw sheaths, body feathers, remiges, retrices
Diagnosis- (after O'Connor et al., 2009) intermembral index (humerus+ulna/.femur+tibiotarsus)
1.23.
Other diagnoses- O'Connor et al. (2009) also list several other characters
in the diagnosis which they state are found in related taxa as well. The snout
length (62% of skull length) is overlapped by Longirostravis (60-64%)
and very similar to Longipteryx (64%) and Rapaxavis (65%). Manual
phalanx II-2 is reduced and wedge-shaped in Longirostravis and Rapaxavis
too. The low interclavicular angle (~40 degrees) is also present in Iberomesornis
and Concornis. The length of the hypocleideum being shorter than the
interclavicular symphysis is not necessarily true, as the authors state the
hypocleideal length is unknown. The distallly non-branched posterolateral sternal
processes are plesiomorphic for enantiornithines. Metatarsal III is longest
plesiomorphically for theropods. O'Connor et al. note Rapaxavis also
has a longitudinal crest on the central portion of its pedal unguals' sides.
Two pairs of elongate retrices are also present in Paraprotopteryx. The
pedal ungual and claw curvature is similar to that of Rapaxavis.
References- O'Connor, Meng, Wang and Chiappe, 2006. Longirostrine enantiornithine
birds; Information from a new Chinese specimen. Journal of Vertebrate Paleontology.
26(3), 106A.
O'Connor, Wang, Chiappe, Gao, Meng, Cheng and Liu, 2009. Phylogenetic support
for a specialized clade of Cretaceous enantiornithine birds with information
from a new species. Journal of Vertebrate Paleontology. 29(1), 188-204.
unnamed clade (Longirostravis hani + Rapaxavis pani)
Diagnosis- less than eight sacral vertebrae; posterolateral sternal process
with tribranched distal tip.
Longirostravis Hou, Chiappe,
Zhang and Chuong, 2004
= "Longirostravis" Hou, Chiappe, Zhang and Chuong, 2003 online
L. hani Hou, Chiappe, Zhang and Chuong, 2004
= "Longirostravis hani" Hou, Chiappe, Zhang and Chuong, 2003 online
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou or Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V11309) (~105 mm, 39 g) skull (~32.86 mm), mandibles,
cervical vertebrae, dorsal vertebrae, dorsal ribs, gastralia, sacrum, five caudal
vertebrae, pygostyle (13.57 mm), scapulae (19.2 mm), coracoids (13.57, ~11.86
mm), furcula (10.71 mm), sternum (17 mm), humeri (23.51, ~25.71 mm), radii (~21.43,
24.57 mm), ulnae (~24.11, ~25.14 mm), proximal carpal, carpometacarpus, manual
phalanges?, ilium (13.8 mm), pubis, ischium, femora (19.43 mm), tibiotarsi (25.17,
25 mm), fibulae, metatarsal I, tarsometatarsus (13.74 mm), pedal phalanges,
feather impressions
Diagnosis- (after Hou et al., 2004) posterolateral sternal process with
cladogram-like three-branched distal end.
(proposed) seven sacral vertebrae (also in Protopteryx).
Other diagnoses- Hou et al. (2004) included two other characters in their
diagnosis. The long tapered snout is also present in Longipteryx, Shanweiniao
and Rapaxavis, while Longipteryx's and Rapaxavis' are also
decurved. Shanweiniao and Rapaxavis share dentation which is as
anteriorly limited.
Comments- The description was first released online on December 2003
but not officially published until January 2004.
References- Hou, Chiappe, Zhang and Chuong, 2004. New Early Cretaceous
fossil from China documents a novel trophic specialization for Mesozoic birds.
Naturwissenschaften. 91(1), 22-25.
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata
PalAsiatica. 44(1), 60-98.
Rapaxavis Morschhauser, Varricchio,
Gao, Liu, Wang, Cheng and Meng, 2009
R. pani Morschhauser, Varricchio, Gao, Liu, Wang, Cheng and Meng,
2009
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (DMNH D2522) (47 g, subadult) skull, mandibles, hyoid, eight
cervical vertebrae, four dorsal vertebrae, dorsal ribs, gastralia, synsacrum,
six caudal vertebrae, pygostyle, anterior scapula, coracoids, furcula, sternum,
anterolateral sternal ossifications, nine sternal ribs (4.7-9.7 mm), humeri,
radii, ulnae, pisiforms, metacarpals I, phalanges I-1, metacarpals II, phalanges
II-1, phalanges II-2, metacarpals III, phalanges III-1, phalanges III-2, ilia,
pubes, ischia, femora, tibiae, fibulae, astragalocalcanea, fused distal tarsals
III+IV, metatarsals I, phalanges I-1, pedal unguals I, metatarsals II, phalanges
II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges III-1, phalanges
III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges
IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths
Diagnosis- (after Morschhauser et al., 2009) six sacral vertebrae; posterolateral
sternal processes with two prominent branches and a smaller third branch; anterolateral
sternal ossifications (also in Concornis).
(after O'Connor et al., 2011) rostrum ~60% of skull length; dentition anteriorly
restricted; premaxillary process of maxilla approximately three times longer
than the jugal process; nasals lacking maxillary process, external nares schizorhinal;
furcula with short interclavicular symphysis and interclavicular angle of 50
degrees; coracoid lateral and sternal margins straight; coracoidal facets of
sternum defining an obtuse angle of approximately 110 degrees; femur 80% the
length of the tibiotarsus; penultimate pedal phalanges longer than preceding
phalanges.
Other diagnoses- Morschhauser et al. (2009) list several other characters
in their diagnosis as well. The long and slightly curved snout is also present
in Longipteryx and Longirostravis. Shanweiniao seems to
have as few dentary teeth as Rapaxavis. Boluochia, Dapingfangornis,
Jibeinia, Longipteryx, Pengornis and Sinornis also
have six free caudal vertebrae. The lack of Longirostravis' antler-shaped
posterolateral sternal processes is plesiomorphic, as is the unexpanded posteromedian
sternal process. The lack of manual unguals I and II is shared with Longirostravis
and Shanweiniao. Having hindlimbs longer compared to the forelimbs than
in Longipteryx is plesiomorphic, with Longirostravis having a
similar ratio. Longirostravis has a similarly long hallux compared to
tarsometatarsal length, as opposed to Longipteryx and Shanweiniao.
Comments- This specimen was first reported by Morschhauser et al. (2006)
as a juvenile Longirostravis or a new related taxon, and was used in
the phylogenetic analysis of O'Connor et al. (2009) before it was named. This
found it to be a longipterygid sister to Longirostravis (though it was
misspelled DMNH D2567/8 in figure 8 and switched with Zhongornis), which
Morschhauser et al. (2009) agreed with when they named and described the taxon
a few months later. O'Connor et al. (2011) redescribed the specimen once it
was fully prepared.
References- Morschhauser, Liu, Meng and Varricchio, 2006. Anatomical
details from a well preserved specimen of Longirostravis (Aves, Enantiornithes)
from the Jiufotang Formation, Liaoning Province, China. Journal of Vertebrate
Paleontology. 26(3), 103A.
Morschhauser, Varricchio, Gao, Liu, Wang, Cheng and Meng, 2009. Anatomy of the
Early Cretaceous bird Rapaxavis pani, a new species from Liaoning Province,
China. Journal of Vertebrate Paleontology. 29(2), 545-554.
O'Connor, Wang, Chiappe, Gao, Meng, Cheng and Liu, 2009. Phylogenetic support
for a specialized clade of Cretaceous enantiornithine birds with information
from a new species. Journal of Vertebrate Paleontology. 29(1), 188-204.
O'Connor, Chiappe, Gao and Zhao, 2011. Anatomy of the Early Cretaceous enantiornithine
bird Rapaxavis pani. Acta Palaeontologica Polonica. 56(3), 463-475.
unnamed clade
Alethoalaornithidae Li, Hu, Duan, Gong and Hou, 2007
Alethoalaornis Li, Hu, Duan,
Gong and Hou, 2007
A. agitornis Li, Hu, Duan, Gong and Hou, 2007
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (LPM coll.; LPM 00009) incomplete skull (27 mm), mandible,
nine cervical vertebrae, nine dorsal vertebrae, dorsal rib fragments, six caudal
vertebrae, pygostyle (16 mm), scapulae, coracoids, furcula, sternum, humeri
(24 mm), radii, ulnae (26 mm), scapholunares, pisiforms, carpometacarpi (23 mm), phalanges
I-1, manual unguals I, phalanges II-1 + III-1, phalanges II-2, manual unguals
II, pubes, femora (24 mm), tibiotarsi (27 mm), fibula, phalanx I-1, pedal ungual
I, tarsometatarsi (17 mm), phalanx II-1, phalanx II-2, pedal ungual II, phalanges
III-1, phalanges III-2, phalanges III-3, pedal ungual III, phalanges IV-1, phalanges
IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, body feathers, remiges
Paratype- (LPM 00038) specimen including skull, cervical vertebrae, dorsal
vertebrae, dorsal ribs, synsacrum, pectoral elements, humeri, radii, ulnae,
carpometacarpi, phalanges I-1, manual ungual I, phalanges II-1, phalanges II-2,
phalanges III-1, partial ilia, pubis(?), femora, tibiotarsi, metatarsal I, phalanx
I-1, pedal ungual I, tarsometatarsi, pedal phalanges, pedal unguals
Referred- ?(LPM 00032) (subadult) specimen including synsacrum, pygostyle,
humeri, radius, ulnae, carpometacarpus, phalanx I-1, femur, tibiotarsu, phalanx
I-1, pedal ungual I, tarsometatarsus, phalanx II-1, phalanx II-2, pedal ungual
II, phalanx IIi-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1,
phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV (Li, Hu, Duan, Gong
and Hou, 2007)
(LPM 00053) specimen including dorsal ribs, gastralia, synsacrum, caudal vertebrae,
pygostyle (~12 mm), incomplete humerus, radius, ulna, partial carpometacarpus,
phalanx II-1, ilium, pubis, femora (one partial), tibiotarsi (one incomplete;
~26 mm), fibula, metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi,
phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx
IIII-3, pedal ungual III, pedal digit IV (Li, Hu, Duan, Gong and Hou, 2007)
?(LPM B00017; = LPM 00040) specimen including skull, mandibles,
cervical vertebrae, dorsal vertebrae, synsacrum, scapula, coracoid,
sternum, humeri, radii, ulnae, pisiform, metacarpal I, phalanx I-1,
manual ungual I, carpometacarpus, phalanx II-1, phalanx II-2, phalanx
III-1, partial femur, tibiotarsus, fibula, metatarsal I, phalanges I-1,
pedal unguals I, tarsometatarsi, phalanges II-1, phalanges II-2, pedal
unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal
unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges
IV-4, pedal unguals IV(Li, Hu, Duan, Gong and Hou, 2007)
Diagnosis- (after Li et al., 2007) hypcleidium equals clavicular ramus
in length.
(after O'Connor, 2009; based on LPM B00017) low and delicate spinal crest on
synsacrum; coracoid with convex lateral margin; sternal margin of coracoid slightly
ventrally concave; lateral corner of distal coracoid distal to medial corner;
sternum with posterolateral processes projecting posteriorly further than posteromedian
process; pneumotricipital fossa rudimentary; deltopectoral crest tapering distally;
manual digit I ~50% length of metacarpal II; manual ungual I larger than ungual
II; tibiotarsus proximal surface angled so that medial margin is elevated compared
to lateral margin; pedal ungual III less recurved than II and IV; proximal half
of pedal unguals with laterally projecting ridges.
Other diagnoses- Li et al. (2007) listed numerous other characters in
their diagnosis of Alethoalaornis and Alethoalaornithidae. The beak does
not seem longer than most enantiornithines (and O'Connor 2009 states preservation
prevents determination of its length), while its apparent sharpness in LPM 00038
is due to preparation and that of LPM 00040 could be due to that or preservation.
Two to three pairs of premaxillary teeth seem to be present in Pengornis.
Heterocoelous cervical vertebrae and thin hypocleidia are present in most enantiornithines.
A "well developed" sternal carina and "metacarpal formed"
are too vague to evaulate. Deep capital grooves are present in all enantiornithines
except Elsornis. O'Connor notes pneumatic foramina are absent in referred
specimen LPM B00017 at least. The manual unguals on digits I and II are reduced
a similar amount in Hebeiornis and Shanweiniao, while many derived
enantiornithines lack an ungual on digit III. Contra their description, the
illustration suggests that the metatarsals increase in length laterally instead
of being equally long. This is also present in Longipteryx and Boluochia.
O'Connor states metatarsal III is longest in LMP B00017 while II and IV are
subequal, which is primitive for theropods. Pedal unguals are longer than their
pedal phalanges in most enantiornithines, including Pengornis, Shanweiniao
and Sinornis.
Comments- Li et al. (2007) named this taxon in a description which was
largely published in Chinese, with only a short English summary. They erected
the new family Alethoalaornithidae for the genus, which they placed in Cathayornithiformes.
This latter assignment was based on "similar length of trochlea at distal
end of tarsometatarsus." If this refers to equal width, it is unlike Sinornis,
which has trochlea II widest, and if it refers to distal extent, it is also
unlike Sinornis which has trochlea III longest (whereas Alethoalaornis
is illustrated as having trochlea IV longest, though LPM B00017 has III longest).
O'Connor (2009) notes the holotype has a new collection number (unknown to her)
as LPM 00009 is now a Confuciusornis specimen. She noted the only specimen
available for study (LPM B00017) is distinguishable from other enantiornmithines,
but because Li et al.'s "diagnosis does not match observations in LPMB00017,
it is possible this specimen is not referable to Alethoalaornis agitornis,
or that the original diagnosis is inaccurate."
Hu et al. (2013) mentioned LPM 00032 (as PMOL-AB00032) as a new enantiornithine
taxon similar to Bohaiornis in size and limb element ratios, but diagnosed
it based on- neural spines of dorsal vertebrae with anteroposteriorly strongly
expanded tips; longitudinally grooved ventral surface of synsacrum; coracoid
with straight lateral margin; clavicular rami medially curved; oval outline
of sternum with posteromedian process distinctly wider than posteroolateral
processes; forelimb and hind limb subequal in length; humeral head flat; manual
digit I extending almost as far distally as metacarpal II.
References- Li, Hu, Duan, Gong and Hou, 2007. Alethoalaornithidae fam.
nov.: A new family of enantiornithine bird from the Lower Cretaceous of Western
Liaoning. Acta Palaeontologica Sinica. 46(3), 365-372.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Hu, Liu, Li, Hou and Xu, 2013. A new large enantiornithine bird from the Lower
Cretaceous of Western Liaoning, China. Journal of Vertebrate Paleontology. Program
and Abstracts 2013, 145.
Gurilynia Kurochkin, 1999
G. nessovi Kurochkin, 1999
Late Campanian-Early Maastrichtian, Late Cretaceous
Gurilin Tsav, Nemegt Formation, Mongolia
Holotype- (PIN 4499-12) proximal humerus
Paratypes- ....(PIN 4499-13) (~510 mm) proximal coracoid (~58 mm)
....(PIN 4499-14) distal humerus
Diagnosis- (after Kurochkin, 1999) acute top of the coracoid process;
very thin dorsal portion of the coracoid shaft; nearly equal length of both
branches in the humeral head, which form an obtuse angle; small anterior fossa
distal to the top of the humeral head angle; absence of a tuberosity depression
on the posterior side of the deleopectoral crest; very shallow posterior depression
on the distal humerus.
(after O'Connor, 2009) proximal anterior surface concave and posterior surface
convex; proximal margin convex on midline, rising dorsally and ventrally; deltopectoral
crest projecting proximally to same level as humeral head; anterior margin shallow
capital incision; proximoventrally restricted ventral tubercle; oval impression
for m. coracobrachialis cranialis demarcated ventrally by defined ridge.
References- Kurochkin, 1999. A new large enantiornithid from the Upper
Cretaceous of Mongolia (Aves, Enantiornithes). Russian Academy of Sciences,
Proceedings of the Zoological Institute. 277, 130-141.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Avimaia Bailleul, O'Connor, Zhang, Li, Wang, Lamanna, Zhu and Zhou, 2019
A. schweitzerae Bailleul, O'Connor, Zhang, Li, Wang, Lamanna, Zhu and Zhou, 2019
Late Aptian, Early Cretaceous
Xiagou Formation, Gansu, China
Holotype-
(IVPP 25371) (1+ year old female) last seven dorsal vertebrae, several dorsal ribs,
synsacrum, two caudal vertebrfae, pygostyle, ilia, pubes, ischium,
incomplete femora, tibiotarsi, proximal fibula, metatarsal I, phalanges
I-1, pedal unguals I, tarsometatarsi (one proximal), phalanx II-1,
phalanx II-2, pedal ungual II, phalanges III-1 (one distal), phalanges
III-2, phalanges III-3, pedal unguals III, phalanges IV-1 (one distal),
phalanges IV-2 (one proximal), phalanges IV-3, phalanges IV-4, pedal
unguals IV, body feathers, partial egg
Paratype-
(CAGS-IG-04-CM-007) fused ilial and ischial fragments, pubes, femora (one partial;
24 mm), tibiotarsi (one proximal; ~29.2 mm), proximal fibula, metatarsal I,
phalanx I-1 (4.3 mm), pedal ungual I (~3.9 mm), tarsometatarsus (II 19.6, III
20.3, IV 19.1 mm), phalanx II-1 (3.6 mm), phalanx II-2 (4.9 mm), pedal ungual
II (4.4 mm), phalanx III-1 (4.8 mm), phalanx III-2 (4 mm), phalanx III-3 (5
mm), pedal ungual III (4.4 mm), phalanx IV-1 (2.8 mm), phalanx IV-2 (2 mm),
phalanx IV-3 (2.2 mm), phalanx IV-4 (3.7 mm), pedal ungual IV (~4.7 mm), fragment,
feathers (Lamanna, You, Harris, Chiappe, Ji, L� and Ji, 2006)
Diagnosis- (after Bailleul et
al., 2019) pubis delicate and strongly curved so that the posterior
margin is concave throughout; distal end of ischium dorsally curved.
Comments- Bailleul et al.
(2019) added this to O'Connor's bird analysis and recovered it deeply
nested in Enantiornithes in a polytomy with CAGS-IG-07-CM-001, Concornis, Enantiophoenix, Eoenantiornis and Neuquenornis.
References-
Lamanna, You, Harris, Chiappe, Ji, L� and Ji, 2006. A partial skeleton
of an enantiornithine bird from the Early Cretaceous of northwestern China.
Acta Palaeontologica Polonica. 51(3), 423-434.
Bailleul, O'Connor, Zhang, Li, Wang, Lamanna, Zhu and Zhou, 2019. An
Early Cretaceous enantiornithine (Aves) preserving an unlaid egg and
probable medullary bone. Nature Communications. 10:1275.
"Cathayornis" aberransis
Hou, Zhou, Zhang and Gu, 2002
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V12353; lost) skull (28 mm), gastralia, coracoids (16
mm), incomplete furcula?, sternum, forelimb elements including humerus (30 mm)
and ulnae (29 mm), carpometacarpi (15 mm), pubes (24.5 mm), proximal tibia,
fibula, numerous other elements
Comments- Described by Hou et al. (2002) in a book which has not yet
been translated to English, making information on this specimen extremely limited.
Of the characters in the original diagnosis, toothed jaws, a well developed
posteriorly distributed sternal keel, humerus slightly shorter than ulna and
distally fused pubes are all plesiomorphic for Enantiornithes. Cathayornis
yandica only differs from these in that its ulna is slightly shorter than
its humerus, but variations of 5-10% are known for other basal birds, so this
doesn't guarantee a valid distinguishing characteristic. The longitudinal ridge
between the frontals (absent according to O'Connor and Dyke, 2010), and tubercles
on "both sides of the frontal" are difficult to evaluate given taphonomy
and the lack of frontal description and preservation in most enantiornithines.
The last proposed diagnostic feature- posterolateral sternal processes shorter
than posteromedian processes, does appear to be valid. This is also present
in Protopteryx, probably Elsornis, Eoenantiornis and Hebeiornis
though. O'Connor and Dyke said further preparation and examination are needed
to validate the species, though Wang and Liu (2016) state the holotype is lost.
Reference- Hou, Zhou, Zhang and Gu, 2002. Mesozoic birds from western
Liaoning in China. ISBN 7-5381-3392-5. 120 pp.
O'Connor and Dyke, 2010. A reassessment of Sinornis santensis and Cathayornis
yandica (Aves: Enantiornithes). Records of the Australian Museum. 62, 7-20.
Wang and Liu, 2016 (online 2015). Taxonomical reappraisal of Cathayornithidae (Aves: Enantiornithes).
Journal of Systematic Palaeontology. 14(1), 29-47.
"Cathayornis" chabuensis
Li, Li, Zhang, Zhou, Bai, Zhang and Ba, 2008
Early Cretaceous
Jingchuan Formation, Inner Mongolia, China
Holotype- (BMNHC Ph 000110) (subadult) ten cervical vertebrae, two cervical
ribs, six dorsal vertebrae, nine dorsal ribs, scapulae (one incomplete; 23 mm),
coracoids (17.6 mm), sternum (21 mm), humeri (one incomplete; 31.8 mm) radii
(34.4 mm), ulnae (36.5 mm), carpometacarpi (one incomplete; 15 mm), phalanx
II-1, phalanx II-2, phalanx III-1, femora (30.8 mm), tibiotarsi (38.6 mm), metatarsal
I, phalanx I-1, pedal ungual I, tarsometatarsi (one partial; 19 mm), phalanx
II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3,
pedal ungual III, feathers
Diagnosis- (after Wang and Liu, 2016) differs from Cathayornis
in- distal edge of posterolateral sternal process rounded (also in Longipteryx;
ontogenetic?); posteromedian sternal process distally blunt; lateral process
at base of posterolateral sternal process absent.
Other diagnoses- Li et al. (2008) use the posteriorly diverging posterolateral
sternal processes to distinguish this species from Cathayornis yandica,
but this is true of most enantiornithines (e.g. Alethoalaornis, Boluochia,
Houornis, Concornis, Dapingfangornis, Elsornis, Eocathayornis, Eoenantiornis,
Hebeiornis, Jibeinia). The authors also distinguished it by its posteromedian
sternal process which extends posteriorly past the posterolateral processes.
This is also found in Protopteryx, Eocathayornis, Eoenantiornis,
Hebeiornis, Shanweiniao and probably Elsornis.
Comments- Li et al. discovered this specimen in 2002 and described it
as a new species of Cathayornis in 2008. They assigned it to Cathayornis
based on several characters. The longitudinal radius groove is present in all
enantiornithines more derived than Longipteryx. Cathayornis actually
has a broad intermetacarpal space (contra Li et al.), with the illusion of a
nearly absent space in some enantiornithines due to postmortem distortion of
the flattened third metacarpal. Several other enantiornithines have only one
phalanx on manual digit III (Alethoalaornis, Concornis, Eoalulavis, Eoenantiornis,
Gobipteryx, Hebeiornis, Sinornis), which is often closely appressed
to phalanx II-1 when articulated (e.g. Eoalulavis, Hebeiornis, Sinornis)
and is actually fused in Alethoalaornis based on its figure. Finally,
Li et al. state "proportions of limb bones" are similar between Cathayornis
and chabuensis. The ulnohumeral ratios are indeed quite similar (98%
vs. 97%), but so are those of Houornis (100%), Rapaxavis (100%)
and Longirostravis (98%). The humerofemoral ratio of chabuensis
(113%) is similar to Cathayornis (117%), but so are Houornis (113%),
Eoenantiornis (111%) and Sinornis (114%). The tibiofemoral ratio
of 127% is again close to Cathayornis' (126%), but so are Dapingfangornis
(126%), Jibeinia (126%), Shanweiniao (128%), Longirostravis
(129%) and Sinornis (124%). The tarsometatarsofemoral ratio of 63% is
a bit lower than Cathayornis' (~66%), with Houornis (63%), Gobipteryx
(~69%), Largirostrornis (67%), Shanweiniao (68%), and Shenquiornis
(64%) all being at least as similar to Cathayornis in this regard. Thus
there are no unique shared characters with Cathayornis and while the
limb proportions are mostly similar, they are not necessarily derived. It is
here excluded from Cathayornis. O'Connor and Dyke (2010) and Wang and
Liu (2016) agreed the characters did not justify referral to Cathayornis.
Both papers agreed it could be distinguished from Cathayornis, though
the latter paper declared it a nomen dubium without stating which taxa it could
not be distinguished from. Wang and Liu found chabuensis to be more closely
related to Hebeiornis than to Cathayornis.
Zhang et al. (2010) referred a new specimen (OFMB-3) from the same locality
to Cathayornis chabuensis, interpreting the differences (broadly triangular
distal expansions of the posterolateral sternal processes; post-costal sternal
processes) as being due to greater ontogenetic age. Wang and Liu (2016) suggested
this could not be demonstrated, and given the lack of shared characters with
chabuensis, declared OFMB-3 indeterminate.
References- Li, Li, Zhang, Zhou, Bai, Zhang and Ba, 2008. A new species
of Cathayornis from the Lower Cretaceous of Inner Mongolia, China and
its stratigraphic significance. Acta Geologica Sinica. 82(6), 1115-1123.
O'Connor and Dyke, 2010. A reassessment of Sinornis santensis and Cathayornis
yandica (Aves: Enantiornithes). Records of the Australian Museum. 62, 7-20.
Zhang, Zhang, Li and Li, 2010. New discovery and flying skills of Cathayornis
from the Lower Cretaceous strata of the Otog Qi in Inner Mongolia, China. Geological
Bulletin of China. 29(7), 988-992.
Wang and Liu, 2016 (online 2015). Taxonomical reappraisal of Cathayornithidae (Aves: Enantiornithes).
Journal of Systematic Palaeontology. 14(1), 29-47.
Cathayornithiformes Zhou, Jin and Zhang, 1992a
Definition- (Cathayornis yandica <- Iberomesornis romeralii, Longipteryx
chaoyangensis, Gobipteryx minuta, Enantiornis leali) (Martyniuk, 2012)
Cathayornithidae Zhou, Jin and Zhang, 1992a
References- Zhou, Jin and Zhang, 1992a. [Preliminary report on a Mesozoic bird
from Liaoning, China]. Chinese Science Bulletin. 5, 435-437.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Cathayornis Zhou, Jin and Zhang,
1992a
C. yandica Zhou, Jin and Zhang, 1992a
?= Cathayornis "shanwangensis" Xu, Yang and Deng, 1999
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V 9769) (63 g) incomplete skull (28.1 mm), mandibles,
five cervical vertebrae (2.7, 2.5 mm), ?fourth dorsal vertebra (2.5 mm), dorsal
ribs, synsacrum (13.1 mm), first caudal vertebra (2 mm), second caudal vertebra,
third caudal vertebra, fourth caudal vertebra, fifth caudal vertebra (1.6 mm),
sixth caudal vertebra, pygostyle (14.4 mm), scapulae (20.4 mm), incomplete coracoids,
furcula, partial sternum (21 mm), sternal rib, humeri (25.7 mm), radii (24.9
mm), ulnae (26.2 mm), scapholunares, pisiforms, carpometacarpi (12.3 mm; metacarpal
I 2.2 mm, metacarpal III 12.6 mm), phalanges I-1 (4.6 mm), manual unguals I
(1.6 mm), phalanges II-1 (6.8 mm), phalanges II-2 (4.3 mm), manual ungual II
(1.1 mm), phalanges III-1 (3.1 mm), ilia (13.9 mm), pubis (~15.4 mm), ischia,
femora (23 mm), tibiotarsi (one incomplete; 29.4 mm), fibulae, metatarsal I
(3 mm), partial tarsometatarsus (mtII 14.8 mm), several pedal phalanges, three
pedal unguals
Referred- ?(DNHM 2510; DNHM 2511) incomplete skeleton including incomplete
skull (O'Connor, 2009)
?(DNHM 2567; DNHM 2568) incomplete skeleton including incomplete skull, scapula,
coracoid, furcula and sternum (O'Connor, 2009)
?(IVPP V9936) tarsometatarsus (mtII ~21.6, mtIII ~22.5, mtIV ~22.3 mm), phalanx
II-1, phalanx II-2, two phalanges III-?, three phalanges IV-?, two pedal unguals,
pedal claw sheath (Zhou, 1999)
?(IVPP V10896) specimen including premaxilla, dentary and coracoid (Martin and
Zhou, 1997)
Diagnosis- (after Zhou et al., 1992) transverse processes of seventh
and eighth sacral vertebrae fusing distally.
(after Zhou, 1999) manual ungual I slightly longer than ungual II [145%] (also
in Bohaiornis 125-150% and Sulcavis 135%).
(after O'Connor and Dyke, 2010) postacetabular process with almost straight
dorsal margin (also in bohaiornithids and Eoalulavis); postacetabular
process less tapered than Sinornis (also in Zhouornis and Eoalulavis).
(after Wang and Liu, 2016) postcostal sternal process.
Other diagnoses- Zhou et al. (1992) included numerous ornithothoracine
symplesiomorphies in their original diagnosis- cranial elements "seldom
fused"; premaxilla toothed; dentary toothed; pygostyle long; "straight
and slender" scapula; strut-like coracoid; sternal keel low; low and flat
humeral head; very small pneumotricipital fossa; semilunate dorsal ulnar condyle;
carpometacarpus; manual unguals present; pelvic bones unfused; fibula "weak"
and unfused with tibia; pedal unguals strongly curved and pointed; pedal unguals
with "undeveloped" extensor tubercles. Other characters are common
in enentiornithines- synsacrum including 8 vertebrae; posterolateral and posteromedial
sternal processes. The foramen magnum is unpreserved, so Zhou et al's listing
it as posteroventrally oriented cannot be verified. Contra Zhou et al., the
metatarsus is fused.
Hou (1997) also included more characters symplesiomorphic for ornithothoracines-
rostrum relatively long and low; pygostyle present; scapula with oblique acromion
process; humeral head small or undeveloped; humeral medial and lateral tuberosities
distinct; ulna robust and slightly curved; small olecranon process; radius slender
with expanded proximal end; carpal trochlea; reduced unguals on first and second
manual digits; fibula is long and "conical" (actually transversely
flattened); pedal unguals not "extremely curved". Other characters
used by Hou are common in enantiornithines- posterolateral sternal processes
well developed with termini expanded as oblique triangles; humerus and ulna
equivalent in length [u/h 102%].
Zhou (1999) listed a supracetabular crest that is anterodorsally developed,
but among advanced enantiornithines this is only otherwise determinable in Sinornis
(present) and Bohaiornis (absent). Other characters listed are common
in enantiornithines- large and shallow metacarpal incision in pisiform; phalanx
III-1 ~50% [46%] of II-1 length; phalanx III-1 expanded proximally. The supposedly
absent antitrochanter is due to damage (O'Connor and Dyke, 2010).
O'Connor and Dyke (2010) listed other characters which differ from Sinornis,
but of these the supposedly blunter postacetabular process tip seems comparable,
and the other two are common in enantiornithines- pygostyle longer [63% of femur
vs. 55%]; manual phalanx III-1 straight.
Wang and Liu (2016) also listed posterolateral sternal process extends further
posteriorly than posteromedian process, which is found in several other derived
enantiornithines. A tapered posteromedian sternal process is primitive. The
supposedly unforked jugal whose posterior end curves dorsally is problematic.
The presence of a posterior process is unclear, and the dorsal half of the apparant
dorsal process may be another element.
Comments- The holotype was discovered in 1990 and first mentioned in
an abstract by Zhou (1992) before being named and described by Zhou et al. (1992).
It was later redescribed in both Hou (1997) and Zhou's (1999) thesis. Cathayornis
yandica was considered a junior synonym of Sinornis santensis by
Sereno et al. (2002), but was revalidated by O'Connor (2009; published as O'Connor
and Dyke, 2010).
Xu et al. (1999) listed Cathayornis shanwangensis as a fossil bird along
with Archaeopteryx, Ichthyornis and Hesperornis in their
announcement of Hebeiornis, but this is near certainly an error (in both
the Chinese and English). As the other three listed genera are famous, the similarly
well known Cathayornis yandica would be expected as opposed to a new
species. It's possible the authors were thinking of the phasianid Shandongornis
shanwanensis from the Miocene Shanwan Series of Shandong, China.
Referred specimens- Hou (1997) includes a photograph of an articulated
pelvis (IVPP coll.) which was illustrated as Cathayornis yandica by Zhou
(1999) and Zhou and Hou (2002) without comment. Martin and Zhou (1997) refer
IVPP V10896 and V10916 to Cathayornis. The latter was made the holotype
of Eocathayornis in 2002, while V10896 was listed as Cathayornis
indet. by O'Connor and Chiappe (2011). Zhou reported "over a dozen"
Cathayornis specimens were known, though he only lists IVPP V10896 and
V9936 as referred specimens, the latter photographed as a referred specimen
by Zhou and Hou. O'Connor and Dyke (2010) incorrectly say Hou referred IVPP
V10533 and V10904 to Cathayornis yandica, but he actually referred these
to C. caudatus (now Houornis). O'Connor (2009) lists DNHM 2510/1
and 2567/8 in her thesis as Cathayornis sp., but otherwise only refers
to them as Enantiornithes or Euenantiornithes indet..
Besides noting basic surangular morphology, DNHM 2510/1 remains undescribed
and is unillustrated, so cannot be evaluated from publications unless O'Connor's
data matrix is examined.
DNHM 2567/8 has postcostal sternal processes, so may be correctly referred to
Cathayornis.
IVPP V9936 is 46% larger than the holotype, but difficult to compare otherwise
as the type's metatarsus is only partially preserved and the few phalanges preserved
in each specimen are disarticulated.
IVPP V10896 was listed as preserving a premaxilla and dentary by O'Connor and
Chiappe, and to have a coracoid 2.5 times longer than wide by Zhou (2002). The
coracoid's dimensions in the holotype are uncertain (estimated at 2.3 by Zhou,
1999), as the preserved coracoid is broken in two with an unknown amount under
the sternum. Wang and Liu (2016) said V10896 "preserves an articulated
pelvic girdle", but this is probably an error referring to the unnumbered
IVPP specimen.
The IVPP articulated pelvis has a highly convex dorsal postacetabular margin
and large amount of taper, unlike Cathayornis, so is probably wrongly
referred. It's listed as an unnamed Jiufotang enantiornithine here.
References- Zhou, 1992. Discovery of new Cretaceous birds in China. Abstracts
of the Third Symposium of the Society of Avian Paleontology and Evolution.
Zhou, Jin and Zhang, 1992a. [Preliminary report on a Mesozoic bird from Liaoning,
China]. Chinese Science Bulletin. 5, 435-437.
Zhou, Jin and Zhang, 1992b. Preliminary report on a Mesozoic bird from Liaoning,
China. Chinese Science Bulletin. 37(16), 1365-1368.
Zhou, 1995. The discovery of Early Cretaceous birds in China. Courier Forschungsinstitut
Senckenberg. 181, 9-22.
Zhou, 1995. New understanding of the evolution of the limb and girdle elements
in early birds - Evidences from Chinese fossils. In Sun and Wang (eds.). Sixth
Symposium on Mesozoic Terrestrial Ecosystems and Biota, short papers. 209-214.
Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park, Lugu Hsiang, Taiwan.
221 pp.
Martin and Zhou, 1997. Archaeopteryx-like skull in enantiornithine bird.
Nature. 389, 556.
Xu, Yang and Deng, 1999. First discovery of Mesozoic bird fossils in Hebei Province
and its significance. Regional Geology of China. 18(4), 444-448.
Zhou, 1999. Early evolution of birds and avian flight- Evidence from Mesozoic
fossils and modern birds. PhD thesis, University of Kansas. 216 pp.
Sereno, Rao and Li, 2002. Sinornis santensis (Aves: Enantiornithes) from
the Early Cretaceous of Northeastern China. In Chiappe and Witmer (eds.). Mesozoic
Birds - Above the Heads of Dinosaurs. University of California Press, Berkeley,
Los Angeles, London. 184-208.
Zhou, 2002. A new and primitive enantiornithine bird from the Early Cretaceous
of China. Journal of Vertebrate Paleontology. 22(1), 49-57.
Zhou and Hou, 2002. The discovery and study of Mesozoic birds in China. In Chiappe
and Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London. 160-183.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
O'Connor and Dyke, 2010. A reassessment of Sinornis santensis and Cathayornis
yandica (Aves: Enantiornithes). Records of the Australian Museum. 62, 7-20.
O'Connor and Chiappe, 2011. A revision of enantiornithine (Aves: Ornithothoraces)
skull morphology. Journal of Systematic Palaeontology. 9(1), 135-157.
Wang and Liu, 2016 (online 2015). Taxonomical reappraisal of Cathayornithidae (Aves: Enantiornithes).
Journal of Systematic Palaeontology. 14(1), 29-47.
Concornithidae Kurochkin, 1996
Concornis Sanz and Buscalioni,
1992
C. lacustris Sanz and Buscalioni, 1992
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Holotype- (LH-2814) (~130 mm, 70 g) four posterior dorsal vertebrae,
dorsal rib fragments, posterior sacrum, first caudal vertebra, second caudal
vertebra, partial scapulae, coracoids, furcula, anterolateral sternal ossification,
sternum, sternal ribs, humerus, incomplete radius, incomplete ulna, carpometacarpus,
phalanx I-1, manual ungual I, phalanx II-1, phalanx II-2, manual ungual II,
phalanx III-1, pubes, ischia, femora (24 mm), tibiotarsi (36 mm), metatarsal
I, phalanx I-1, pedal ungual I, tarsometatarsus (22 mm), phalanx II-1, phalanx
II-2, partial pedal ungual II, proximal phalanx III-1, phalanx IV-1, phalanx
IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, feather impressions
References- Sanz and Buscalioni, 1992. A new bird from the Early Cretaceous
of Las Hoyas, Spain, and the early radiation of birds. Palaeontology. 35, 829-845.
Sanz, Chiappe and Buscalioni, 1995. The osteology of Concornis lacustris
(Aves: Enantiornithes) from the Lower Cretaceous of Spain and a reexamination
of its phylogenetic relationships. American Museum Novitates. 3133, 23 pp.
Sanz, P�rez-Moreno, Chiappe and Buscalioni, 2002. The birds from the
Lower Cretaceous of Las Hoyas (Privince of Cuenca, Spain). In Chiappe and Witmer
(eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University of California
Press, Berkeley, Los Angeles, London. 209-229.
Dalingheornis Zhang, Hou, Hasegawa,
O'Connor, Martin and Chiappe, 2006
D. liweii Zhang, Hou, Hasegawa, O'Connor, Martin and Chiappe,
2006
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (CNU VB2005001) (juvenile) skull (20 mm), mandibles, ten cervical
vertebrae, cervical ribs, eleven dorsal vertebrae, eighteen dorsal ribs, sternal
ribs, eight sacral vertebrae, twenty caudal vertebrae (17.5 mm), chevrons, scapulae
(8 mm), coracoids (6 mm), furcula (5 mm), posterolateral sternal processes,
humeri (14 mm), radii, ulnae (14 mm), scapholunare, pisiform, semilunate carpal, metacarpal
I, phalanx I-1, metacarpal II (6 mm), phalanx II-1, phalanx II-2, manual ungual
II, metacarpal III (6 mm), ilia (8 mm), pubis (8 mm), ischium (4 mm), femora
(11 mm), tibiae (16 mm), astragalus, calcaneum, metatarsal I, phalanx I-1, pedal
ungual I, metatarsal II, phalanx II-1, phalanx II-2, pedal ungual II, metatarsal
III (9 mm), phalanx III-1, phalanx III-2, proximal phalanx III-3, pedal ungual
III, metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4,
pedal ungual IV, feather impressions
Comments- O'Connor (2009) considers this to be a nomen dubium and a
nomen nudum as it is supposedly in a private collection, but the original description
has it placed in a university, and the repository is unrelated to validity.
References- Zhang, Hou, Hasegawa, O'Connor, Martin and Chiappe, 2006.
The first Mesozoic heterodactyl bird from China. Acta Geologica Sinica. 80(5),
631-635.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Dapingfangornis Li,
Duan, Hu, Wang, Cheng and Hou, 2006
D. sentisorhinus Li, Duan, Hu, Wang, Cheng and Hou, 2006
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (LPM 00039) skull (28 mm), sclerotic plates, mandibles, hyoids,
cervical vertebrae, dorsal vertebrae, dorsal ribs, sacrum, six caudal vertebrae,
pygostyle (15 mm), furcula, sternum (17 mm), scapulae, coracoids (15 mm), humeri
(22 mm), radii, ulnae (27 mm), phalanx I-1, manual ungual I, carpometacarpi
(11 mm), phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, ilia,
pubes, ischia, femora (23 mm), tibiotarsi (29 mm), fibula, metatarsal I, phalanx
I-1, pedal ungual I, tarsometatarsi (16 mm), phalanx II-1, phalanx II-2, pedal
ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx
IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, feather impressions
Diagnosis- (after Li et al., 2006) straight lateral coracoid edge; short
hypocleidium; articular surfaces for coracoids on sternum at small angle (~100
degrees) to each other; distal expansion of posterolateral sternal process hooked
anterolaterally; elongate ulna (>107% of humeral length); extremely slender
radius (~30% of ulnar width) (?); elongate metacarpal I (~34-40% of metacarpal
II length) (?); metatarsal II trochlea not significantly wider than metatarsal
III trochlea (?).
Other diagnoses- Li et al. (2006) listed numerous features in their diagnosis.
The supposedly sharp rostrum is due to the dorsal snout being either crushed
or missing. The supposed median nasal horn is questionable. I wouldn't be surprised
if it were the standard maniraptoriform laterally projected lacrimal 'horn',
viewed ventrally. This would make sense, because the frontal's concave upper
margin would then be the lateral orbital margin in life. O'Connor (2009) agrees,
saying "a nasal crest cannot be confirmed although at this time, it also
cannot be entirely refuted." The frontal is domed posteriorly as typical
for birds, not flat. O'Connor notes the dentary is not longer than in other
enantiornithines, nor are the teeth more widely spaced. The "high feathered
crown" is a taphonomic illusion often seen in feathered Jehol specimens.
Description- What appear to be parietals are preserved posterior to the
skull, as seen in the photo of the skeleton (though they aren't illustrated).
The ventral margin of the skull is very well preserved, with a maxilla strongly
resembling Hebeiornis' and a typical bowed enantiornithine-grade jugal
with an expanded anterior end. The 'tympanic' is actually one of the few well
preserved enantiornithine-grade quadratojugals. O'Connor (2009) notes at least
three maxillary teeth and seven dentary teeth are preserved, contra the at least
six maxillary and ten dentary teeth reported by Li et al. (2006). The described
'palatines' are closer in position to pterygoids. The fenestra posteroventral
to the 'nasal horn' appears to be a broken or disarticulated space between the
frontal and nasal/lacrimal. Two sclerotic plates are apparent, but I don't know
what Li et al. identified as a vomer or lacrimal.
The dentaries seem to have an elongate posterodorsal process, which combined
with the surangular's outline, indicate a large external mandibular fenestra.
I can't identify what Li et al. describe as a prearticular or articular.
The cervical vertebrae are described as heterocoelous, but this could be only
partial heterocoely. The presence of at least eight sacral vertebrae indicate
an ornithothoracine, while the long pygostyle is characteristic of basal avebrevicaudans.
The furcula is said to have a short hypocleidium, which would be atypical of
enantiornithine-grade birds (though known in juveniles and Aberratiodontus).
Notably there is no other evidence this is a young individual, as the sternal
posterolateral processes are present, the carpometacarpus and tarsometatarsus
are fused, and the pygostyle is completely fused. There is a furcula-shaped
structure in the illustration, but it's so atypical (one clavicular branch more
slender and drawn unfused to the rest; hypocleidium extends posterolaterally;
interclavicular angle comparable to basal pygostylians) that either it was drawn
exceedingly poorly or not all of it is supposed to be a furcula (or both).
The short sternum with fused distal posterolateral processes indicate an enantiornithine-grade
bird. The anterior margin is more acute than most eumaniraptorans, with the
exceptions of Longirostravis, Aberratiodontus, Cuspirostrisornis,
Yanornis and Ambiortus. The posterolateral processes end in small
expansions, as in Jibeinia, Protopteryx, Boluochia, Hebeiornis
and Aberratiodontus. However, Dapingfangornis' are apomorphically
hooked anterolaterally. The posteromedial processes are very poorly developed,
as in Protopteryx, Longipteryx and Hebeiornis (Aberratiodontus
lacks them entirely). The posteromedian process is unexpanded, as in Jibeinia,
Protopteryx, Longipteryx, Boluochia, Hebeiornis,
Eoenantiornis, Cathayornis and Aberratiodontus.
The illustration would suggest an ulnar sesamoid and three elongate metacarpals
(II-IV), but I ascribe this to the artist instead of the specimen. The radius
is drawn as much more slender than most Mesozoic birds, and this could be due
to artistic inaccuracy as well. The first metacarpal as illustrated is longer
than any other birds except confuciusornithids. Phalanx I-1 is comparable in
length to Jibeinia and enantiornithine-grade birds (except Protopteryx,
Longipteryx and Eoalulavis). Phalanx II-2 is shorter (compared
to II-1) than other coelurosaurs except Jibeinia, Hebeiornis,
Cathayornis, Sinornis and Eocathayornis. Metacarpal III is illustrated
as subequal or barely passing metacarpal II distally, which would be odd for
an enantiornithine-grade bird and more like euornithines and more basal birds.
It may be due to inaccurate illustration. Digit III seems to only have one phalanx,
though I wouldn't be surprised if a tiny second one were present but not illustrated.
This would be unlike Jibeinia and most more basal birds.
Relationships- Li et al. assign Dapingfangornis to the Eoenantiornithiformes
because of a short skull, larger nasals and similar sternum. I disagree. The
craniofemoral ratio of Dapingfangornis is 1.22, while Eoenantiornis'
is 1.32. These are longer than Aberratiodontus (1.07), Hebeiornis
(1.05) and Cuspirostrisornis (.99), but comparable to Cathayornis
(1.22) and Sinornis (1.26). Protopteryx (~1.42), Longipteryx
(1.90) and Longirostravis (1.80) have longer skulls. Even assuming the
nasals are correctly identified in Dapingfangornis, elongate nasals are
primitive for birds. The sterna are not very similar, as noted above. Eoenantiornis
has a more obtuse anterior margin, large distal expansions on the posterolateral
processes (contra Hou et al., 1999), and prominant posteromedial processes.
Li et al. distinguish the genera by Dapingfengornis' dubious nasal horn,
primitive (and overemphasized by taphonomy) sharp snout, apparently short hypocleidium,
and sternal keel (which is unknown in Eoenantiornis because the sternum
is in dorsal view; contra Hou et al.,1999).
Reference- Li, Duan, Hu, Wang, Cheng and Hou, 2006. New eoenantiornithid
bird from the Early Cretaceous Jiufotang Formation of Western Liaoning, China.
Acta Geologica Sinica. 80(1), 38-41.
Dunhuangia Wang, Li, O'Connor, Zhou
and You, 2015
D. cuii Wang, Li, O'Connor, Zhou and You, 2015
Late Aptian, Early Cretaceous
Xiagou Formation, Gansu, China
Holotype- (CAGS-IG-05-CM-030) gastralia, scapulae (one incomplete), coracoids
(18.3 mm), partial furcula, sternum (24.1 mm), sternal ribs, incomplete humeri,
incomplete radii, incomplete ulnae, pisiforms, carpometacarpi (17.1 mm; mcI 2.9
mm), phalanx I-1 (4.8 mm), manual ungual I (2.5 mm), phalanges II-1 (8.8 mm),
phalanges II-2 (6.1 mm), manual ungual II (2.6 mm), phalanges III-1 (3.7 mm)
Diagnosis- (after Wang et al., 2015) dorsal fossa of coracoid defined
laterally by thick ridge which extends further laterally and forms dorsoventrallycompressed
lateral margin; sternum bearing elongated posterolateral process measuring more
than half length of sternum.
Comments- Discovered in 2005, this was described as a new taxon of enantiornithine
sister to Fortunguavis by Wang et al. (2015).
Reference- Wang, Li, O'Connor, Zhou and You, 2015. Second species of
enantiornithine bird from the Lower Cretaceous Changma Basin, northwestern China
with implications for the taxonomic diversity of the Changma avifauna. Cretaceous
Research. 55, 56-65.
Elbretornis Walker and Dyke,
2009
E. bonapartei Walker and Dyke, 2009
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4022) scapula, incomplete coracoid, humerus (90.2 mm),
proximal radius, proximal ulna
Referred- ?(PVL 4027) distal tibiotarsus (78.5 mm) (Chiappe, 1996)
?(PVL-4041-2) two dorsal vertebrae
....(PVL-4041-4) dorsal rib fragment, sacrum fused to ilia (41 mm), femur (Chippe
and Walker, 2002)
?(PVL-4047) dorsal vertebrae (Chiappe and Calvo, 1994)
?(PVL-4051) six dorsal vertebrae
Diagnosis- (after Walker and Dyke, 2009) dorsal tuberculum of humerus
strongly projected; mediolateral angle of proximal humerus slanted; large and
deeply excavated pneumatic fossa on proximal end containing a deep, rounded
and wide pneumatic foramen that undercuts the shaft; pneumatic foramen located
distally within fossa; absence of an olecranon fossa on the caudal face of the
distal humerus; condylus dorsalis bulbous and not angled transversely; absence
of a bridge crossing the caudal portion of the shaft of the coracoid; welldeveloped
and caudally orientated processus lateralis of coracoid; well-developed and
concave sternal facet of coracoid turned somewhat onto the dorsal face; very
large circular foramen nervi supracoracoidei that opens into the dorsal fossa
of the coracoid; external cotyla of ulna deep and cup-shaped; ulna shorter than
humerus; radius two-thirds the width of the ulna.
Comments- PVL-4022 includes a humerus illustrated by Chiappe and Walker
(2002), though noted (without reference to a specimen number) as early as Walker
(1981) for being unique among Lecho enantiornithines in having a pneumotricipital
foramen. It's an enantiornithine based on- well-developed fossa on the midline
of the proximal humerus making the articular surface appear V-shaped in proximal
view; ventrodistal margin of humerus projected significantly distal to dorsodistal
margin, distal margin angling strongly ventrally (also in Piksi and Apsaravis);
proximoposterior surface of deltopectoral crest concave (also in Confuciusornis,
Apsaravis and Ichthyornis); long axis of dorsal condyle of humerus
almost transversely oriented (also in Yanornis and Apsaravis).
Within Enantiornithes, it is derived based on the proximal edge of humeral head
which is centrally concave and the hypertrophied bicipital crest.
PVL-4041 and 4051 were first reported and commented on by Chiappe and Calvo
(1994), and later illustrated by Chiappe and Walker (2002). Both of these specimens
are Enantiornithes at least as derived as Iberomesornis due to the centrally
located posterior dorsal parapophyses.
PVL-4041-4 is a synsacrum and articulated ilia illustrated by Chiappe and Walker
(2002). The ilia contact over the sacrum, which is otherwise only known in neognaths
(Chiappe and Walker note it may be due to distortion). However, the ilium does
not extend anterior to the sacral vertebrae, unlike Gansus and Aves.
Furthermore, the postacetabular process is vertically oriented, unlike Carinatae
sensu Chiappe. The presence of eight sacral vertebrae establishes the specimen
as an enantiornithine as derived as Iberomesornis or an ornithothoracine.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Enantiornithes (Aves)
from the Upper Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology.
14, 230–246.
Chiappe, 1996. Late Cretaceous birds of southern South America: anatomy and
systematics of Enantiornithes and Patagopteryx deferrariisi. Munchner
Geowissenschaftliche Abhandlungen (A). 30, 203–244.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Elektorornis Xing, O'Connor, Chiappe, McKellar, Carroll, Hu, Bai and Lei, 2019
E. chenguangi Xing, O'Connor, Chiappe, McKellar, Carroll, Hu, Bai and Lei, 2019
Early Cenomanian, Late Cretaceous
Angbamo, Myanmar
Holotype- (HPG-15-2) (subadult or adult) forelimb fragments(?), distal femora, tibiotarsi, fibula, metatarsals I, phalanges
I-1, pedal unguals I, tarsometatarsi (7.7 mm), phalanges II-1,
phalanges II-2, pedal unguals II, phalanges III-1, phalanges
III-2, phalanges III-3, pedal unguals III, phalanges IV-1,
phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal
unguals IV, pedal claw sheaths, skin, body feathers, remiges
Diagnosis- (after Xing et al.,
2019) pedal digit III 20% longer than tarsometatarsus; hallux more than
86% length of pedal digit II; pedal digit II 59% length of digit III.
Comments- Discovered prior to
January 2019. "Diffuse traces of pigments within the barbules
give the wing an overall dark brown color, with paler barb rami and
rachises, and with two large-scale pale wing spots visible anteriorly.
Entire barb apices within the posterior vanes of the primaries are
either pale or white in color, which would have made the underside of
the wing pale or striped." Xing et al. (2019) added this to
O'Connor's avialan matrix and recovered it as a euenantiornithine in a
polytomy with Elsornis, Enantiophoenix, Eoenantiornis, Halimornis and avisaurids.
Reference- Xing, O'Connor,
Chiappe, McKellar, Carroll, Hu, Bai and Lei, 2019. A new
enantiornithine bird with unusual pedal proportions found in amber.
Current Biology. 29(4), 2396-2401.e2.
Clark and O'Connor, 2021. Exploring the ecomorphology of two Cretaceous
enantiornithines with unique pedal morphology. Frontiers in Ecology and
Evolution. 9:654156.
Elsornis Chiappe, Suzuki, Dyke, Watabe,
Tsogtbaatar and Barsbold, 2007
= "Elsornis" Chiappe, Suzuki, Dyke, Watabe, Tsogtbaatar and Barsbold,
2006 online
E. keni Chiappe, Suzuki, Dyke, Watabe, Tsogtbaatar and Barsbold,
2007
= "Elsornis keni" Chiappe, Suzuki, Dyke, Watabe, Tsogtbaatar and Barsbold,
2006 online
Late Campanian, Late Cretaceous
Tugrikin Shire, Djadokhta Formation, Mongolia
Holotype- (MPD-b 100/201; 980725 TS-V Bird SZK) two posterior cervical vertebrae, two anterior
dorsal vertebrae, few dorsal ribs, partial scapulae (63 mm), coracoids (41.7
mm), incomplete furcula, incomplete sternum (>58.55 mm), humeri (77.3 mm),
radii (60.65, 60.48 mm), ulnae (66.68 mm), partial carpometacarpi, three pedal
phalanges, four pedal unguals, fragments
Diagnosis- (after Chiappe et al., 2007) brachial index (humeral length:ulnar
length ratio) substantially greater than 1; scapular shaft with an abrupt bend
on its cranial quarter; cranial margin of sternum subdivided in three distinct
segments due to widely spaced coracoidal sulci; distal symphysis of the major
and minor metacarpals extending for at least one-third the total length of the
carpometacarpus.
Comments-
The holotype was discovered on August 25 1998 and first reported in a few meeting
abstracts in 1999 (Suzuki and Watabe, 1999; Suzuki et al., 1999a,
b). It was first photographed
(as "Forelimb bones of an enantiornithine bird at Tugrikin Shire") by
Suzuki and Watabe (2000). The description was first available
online December 2006 but was not officially published until May 2007.
References-
Suzuki and Watabe, 1999. New occurrence of enantiornithine bird from
the Upper Cretaceous of Mongolia. Paleontological Society of Japan
Annual Meeting, Abstracts. 48.
Suzuki, Watabe and Tsogtbaatar, 1999a. A new enantiornithine bird from
the Upper Cretaceous Djadokhta Formation of Gobi desert, Mongolia.
Geological Society of Japan Annual Meeting 104, Abstracts. 209.
Suzuki, Watabe and Tsogtbaatar, 1999b. A new enantiornithine bird from
the Upper Cretaceous Djadokhta Formation of Gobi desert, Mongolia. Journal of Vertebrate Paleontology. 19(3), 79A.
Suzuki and Watabe, 2000. Report on the Japan-Mongolia Joint
Paleontological Expedition to the Gobi desert, 1998. Hayashibara Museum
of Natural Sciences Research Bulletin. 1, 83-98.
Chiappe, Suzuki, Dyke, Watabe, Tsogtbaatar and Barsbold, 2007.
A new enantiornithine bird from the Late Cretaceous of the Gobi Desert. Journal
of Systematic Palaeontology. 5(2), 193-208.
Enantiornithiformes Martin, 1983
Definition- (Enantiornis leali <- Gobipteryx minuta) (Martyniuk,
2012)
"Enantiornithidae" Nessov and Borkin, 1983
Enantiornithidae Nesov, 1984
Comments- Nessov and Borkin (1983) mentioned the proximal tarsometatarsus
ZIN PO 3494 as a member of Enantiornithidae, but as they do not list a diagnosis
or definition for the family, it was a nomen nudum at the time. This makes the
nominal author Nesov (1984), who references the Martinavis? vincei humerus
and notes enantiornithid humeri have dorsal condyles more transversely oriented
than in alexornithids.
References- Martin, 1983. The origin and early radiation of birds. in
Brush and Clark, (eds.). Perspectives in Ornithology. 291-338.
Nessov and Borkin, 1983. New records of bird bones from Cretaceous of Mongolia
and Middle Asia. Trudy Zoologicheskogo Instituta AN SSSR. 116, 108-110.
Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Enantiornis Walker, 1981
E. leali Walker, 1981
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4035) (~1.0 m) proximal scapula (~89 mm), coracoid (77.2
mm), proximal humerus (~151 mm)
Referred-
(PVL-4020) scapula (75.4 mm), incomplete coracoid (66.4 mm), humerus
(141.2 mm), proximal radius (142.1 mm), ulnae (one proximal; 146 mm),
scapholunare, pisiform, proximal carpometacarpus, phalanx I-1 (lost),
manual ungual I (lost) (Chiappe, 1996)
(PVL-4029) incomplete coracoid (~65 mm) (Chiappe and Calvo, 1994)
(PVL-4039) scapula (89 mm) (Walker, 1981)
(PVL-4055) scapula (78.5 mm) (Chiappe, 1996)
(PVL-4181) ulna (Chiappe, 1996)
(PVL-4266) proximal humerus (Chiappe, 1996)
(PVL-4267) ulna (Chiappe, 1996)
(PVL-4271) coracoid (Chiappe, 1996)
Diagnosis- (after Walker and Dyke, 2009) large perforating, pneumatic
foramen on distal ulna; scapula with distinct depression in the acromion process
(anterior to the coracoid articulation), and a narrow notch just ventral to
it; coracoid with fenestra in the medial wall of the neck; humerus with narrow
pneumatic fossa, sometimes perforated by a canal running proximodistally through
the internal tuberosity; bicipital crest markedly projected cranially; external
tuberosity rises above the level of the humeral head in caudal view; medial
edge of the internal condyle of the ulna straight; large pit present in ventral
view above the distal articulation of the ulna (this contains the large foramen)
Comments- Walker (1981) named this taxon and based it on PVL-4035, of
which only the coracoid was illustrated. The Lecho enantiornithine was described
briefly, but the only explicit mention of Enantiornis' characters were
several features in a table. Chiappe (1996) described the taxon more fully and
listed other specimens as being referred, illustrating the rest of the holotype.
Some referred elements were later illustrated by Chiappe and Walker (2002).
PVL-4029 was illustrated by Chiappe and Calvo (1994) as an enantiornithine,
and was referred to Enantiornis by Walker and Dyke (2009). PVL-4266 is
a proximal humerus photographed by Chiappe (1996) which was assigned to E.
leali by Walker and Dyke. While PVL-4049 was originally illustrated by Walker
(1981) then referred to Enantiornis by Chiappe and Walker (2002), Walker
and Dyke (2009) placed it in Martinavis instead.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Enantiornithes (Aves)
from the Upper Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology.
14, 230-246.
Chiappe, 1996. Early avian evolution in the southern hemisphere: The fossil
record of birds in the Mesozoic of Gondwana. Memoirs of the Queensland Museum.
39(3), 533-554.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
E? sp. nov. (Chiappe, 1991)
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Material- ?(PVL-4023) proximal ulna (~165 mm) (Chiappe, 1996)
(PVL-4043) proximal humerus (~156 mm) (Chiappe, 1991)
Comments- The proximal humerus PVL-4043 was photographed by Chiappe (1991)
and is an enantiornithine based on the well-developed fossa on the midline of
the proximal humerus, making the articular surface appear V-shaped in proximal
view. Additional characters shared with derived enantiornithines include the
proximally concave humeral head and hypertrophied bicipital crest. Walker and
Dyke (2009) tentatively assigned it to Enantiornis leali, but noted it
was anatomically distinct and probably a different taxon.
The proximal ulna PVL-4023 was referred to E. leali by Chiappe (1996),
and later more tentatively referred to the species by Walker and Dyke (2009).
The latter authors find it is larger than other specimens and differs in the
shape of its internal cotyla. As PVL-4043 also differs from E. leali
in minor details and is larger, they are both provisionally listed here in the
same species.
Reference- Chiappe, 1991. Cretaceous birds of Latin America. Cretaceous
Research. 12(1), 55-63.
Chiappe, 1996. Early avian evolution in the southern hemisphere: The fossil
record of birds in the Mesozoic of Gondwana. Memoirs of the Queensland Museum.
39(3), 533-554.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
E. sp. indet. (Walker, 1981)
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Material- ?(PVL-4021-2) fragmentary sternum (Chiappe and Calvo, 1994)
?(PVL-4042) incomplete pelvis (ilium 64 mm) (Walker, 1981)
?(PVL-4045) synsacrum (Chiappe, 1996)
?(PVL-4050) fifth or sixth cervical vertebra (Chiappe, 1996)
?(PVL-4057) mid cervical vertebra (Chiappe, 1996)
?(PVL-4058) distal tarsometatarsus (Chiappe, 1996)
?(PVL-4272) partial coracoid (Walker and Dyke, 2009)
Comments- This material was referred to Enantiornis sp. by Walker
(unpublished) and later Walker and Dyke (2009) based on size. Walker also initially
referred the hindlimb material that was later named Lectavis and Yungavolucris
to Enantiornis. Walker and Dyke (2009) later noted it was likely that
Lectavis is Enantiornis based on size and associations.
PVL-4021-2 is a sternum noted by Chiappe and Calvo (1994) as having deep posterior
notches. It shares the same specimen number with Lectavis, though Walker
(unpublished) considered the association doubtful.
PVL-4042 is a pelvis missing most of the pubis and the distal ischium, illustrated
by Walker (1981) and later Chiappe and Walker (2002) (where it is mislabeled
PVL-4032-3). Walker et al. (2007) stated it was consistant in size with Enantiornis,
which was formalized by Walker and Dyke (2009). The complete pelvic fusion is
more similar to euornithines than enantiornithines, though the elongate proximodorsal
ischial process is only known in confuciusornithids and enantiornithines and
the m. cuppedicus fossa is unlike euornithines. The low pointed postacetabular
process is a symplesiomorphy only retained in Archaeorhynchus among euornthines,
though found in most enantiornithines (except Gobipteryx).
PVL-4050 and 4057 are mid cervical vertebrae noted by Chiappe (1996) and Chiappe
and Walker (2002) which are avialan due to their heterocoelous
anterior surfaces, but unlike most euornithines (except Archaeorhynchus,
Yixianornis, Gansus and Ichthyornis) in lacking heterocoelous
posterior surfaces. Their centra are highly compressed tranversely, as in enantiornithines
and Ichthyornis.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Enantiornithes (Aves)
from the Upper Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology.
14, 230-246.
Chiappe, 1996. Late Cretaceous birds of southern South America: anatomy and
systematics of Enantiornithes and Patagopteryx deferrariisi. Munchner
Geowissenschaftliche Abhandlungen (A). 30, 203-244.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Eocathayornis Zhou, 2002
E. walkeri Zhou, 2002
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype-
(IVPP V10916) (56 g) premaxilla, maxilla, lacrimal?, jugal?,
quadratojugal?, frontal, parietals, quadrate, basicranium?, dentaries,
articular, hyoid, six cervical vertebrae, dorsal vertebrae, several
partial dorsal ribs, four caudal vertebrae, proximal pygostyle,
scapula, coracoids (13.6 mm), sternum (18.5 mm), sternal ribs, humeri
(23.5 mm), radii (25.6 mm), ulnae (26 mm), scapholunare, pisiform,
carpometacarpus (14 mm), phalanx I-1 (6 mm), manual ungual I (2.1 mm),
phalanx II-1 (7 mm), phalanx II-2 (4.3 mm), manual ungual II (2.4 mm),
phalanx III-1 (2.5 mm), manual ungual III (1.3 mm)
Comments- Collected in 1994, Martin and Zhou (1997) first referred this
specimen to Cathayornis.
References- Martin and Zhou, 1997. Archaeopteryx-like skull in
Enantiornithine bird. Nature. 389, 556.
Zhou, 2002. A new and primitive enantiornithine bird from the Early Cretaceous
of China. Journal of Vertebrate Paleontology. 22(1), 49-57.
Eoenantiornithiformes Hou, Martin, Zhou and Feduccia, 1999
Definition- (Eoenantiornis buhleri <- Cathayornis yandica, Iberomesornis
romeralii, Enantiornis leali) (Martyniuk, 2012)
Eoenantiornithidae Hou, Martin, Zhou and Feduccia, 1999
Definition- (Eoenantiornis buhleri <- Longipteryx chaoyangensis,
Cathayornis yandica, Enantiornis leali) (Martyniuk, 2012)
References- Hou, Martin, Zhou and Feduccia, 1999. Archaeopteryx to opposite
birds - missing link from the Mesozoic of China. Vertebrata PalAsiatica. 37(2),
88–95.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Eoenantiornis Hou, Martin,
Zhou and Feduccia, 1999
E. buhleri Hou, Martin, Zhou and Feduccia, 1999
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V11537) (135 mm, 80 g) incomplete skull (22 mm), mandibles,
hyoid, eleven cervical vertebrae (~29 mm), dorsal vertebrae, several dorsal
ribs, two uncinate processes, gastralia, anterior sacrum, several caudal vertebrae,
distal pygostyle, scapula, coracoids (12.5 mm), furcula, sternum, humerus (29.5
mm), partial radii, incomplete ulnae (31 mm), scapholunare?, pisiforms, carpometacarpi
(12 mm), phalanx I-1, manual ungual I, phalanx II-1, phalanx II-2, manual ungual
II, phalanx III-1, partial ilium, distal pubes, distal ischium, incomplete femur
(26.5 mm), tibiotarsus (31 mm), metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsus
(22.3 mm), phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, feather
impressions
Comments- Hou et al. (1999) initially interpreted the sternum as lacking
posterolateral processes, but Zhou et al. (2005) reinterpreted a supposed distal
humerus as one. This was later called into question by O'Connor (2012).
References- Hou, Martin, Zhou and Feduccia, 1999. Archaeopteryx
to opposite birds - Missing link from the Mesozoic of China. Vertebrata PalAsiatica.
37(2), 88-95.
Zhou, Chiappe and Zhang, 2005. Anatomy of the Early Cretaceous bird Eoenantiornis
buhleri (Aves: Enantiornithes) from China. Canadian Journal of Earth Sciences.
42, 1331-1338.
O'Connor, 2012. A revised look at Liaoningornis longidigitrus (Aves).
Vertebrata PalAsiatica. 50(1), 25-37.
Flexomornis Tykoski and Fiorillo,
2010
F. howei Tykoski and Fiorillo, 2010
Middle Campanian, Late Cretaceous
Lewisville Member of the Woodbine Formation, Texas, US
Holotype- (DMNH 18137) incomplete scapula (~64 mm), distal ?humerus, proximal
carpometacarpus, proximal tibiotarsus, several fragments
Diagnosis- (after Tykoski and Fiorillo, 2010) scapular blade dorsoventrally
broad and mediolaterally laminar; scapula lacks a medial longitudinal groove;
scapula has a distinct ventral bend in the blade axis in mediolateral view;
crests along the anterodorsal margins of metacarpals II and III.
Comments- This was described as an enantiornithine perhaps related to
Elsornis based on the ventrally bent scapula and bowed carpometacarpus.
Reference- Tykoski and Fiorillo, 2010. An enantiornithine bird from the
lower middle Cenomanian of Texas. Journal of Vertebrate Paleontology. 30(1),
288-292.
Fortunguavis Wang, O'Connor
and Zhou, 2014
F. xiaotaizicus Wang, O'Connor and Zhou, 2014
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V18631) (adult) skull, mandibles, atlas, several cervical
vertebrae, eight dorsal vertebrae, dorsal ribs, gastralia, synsacrum, four-six
caudal vertebrae, pygostyle (19.84 mm), incomplete scapula, coracoids (22.5 mm), incomplete
furcula, incomplete sternum, sternal ribs, humeri (one partial; 43.6 mm), radii
(46.8 mm), ulnae (one partial), scapholunare, pisiform, carpometacarpi (21.9, 21.4
mm), phalanges I-1 (9.9, 9.8 mm), manual unguals I (4.8 mm), phalanges II-1
(11, 10.9 mm), phalanges II-2 (6.8, 7 mm), partial manual ungual II, phalanges
III-1 (6, 5.7 mm), phalanx III-2, manual claw sheaths, ilium, pubes, ischia,
femora (~41 mm), tibiotarsi (47, 49.2 mm), fibulae, metatarsals I, phalanges
I-1 (5.9 mm), pedal unguals I (7.1 mm), tarsometatarsi (25.3, 25.6 mm), phalanx
II-1 (6 mm), phalanges II-2 (8.5 mm), pedal unguals II (10 mm), phalanges III-1
(7.6 mm), phalanges III-2 (6.8 mm), phalanges III-3 (6.8 mm), pedal unguals
III (~7.4 mm), phalanx IV-1 (4.5 mm), phalanx IV-2 (3.8 mm), phalanx IV-3 (3.1
mm), phalanx IV-4 (4.1 mm), phalanx IV-?, pedal unguals IV (~5.2 mm), pedal
claw sheaths, body feathers, remiges
Diagnosis- (after Wang et al., 2014) dorsoventrally bowed clavicular
ramus; straight to weakly concave lateral margin of coracoid; well-developed
alular digit with large and strongly recurved ungual; large pubic foot with
recurved tip; metatarsal II reduced, not reaching proximal margin of metatarsal
IV trochlea; stout and robust pedal phalanges; strongly recurved pedal unguals.
Comments- Wang et al. (2014) entered Fortunguavis into O'Connor's
analysis and found it to emerge in a polytomy with most enantiornithines except
non-longipterygid-grade taxa, Protopteryx, Elsornis and Iberomesornis.
References- Wang, O'Connor and Zhou, 2014. A new robust enantiornithine
bird from the Lower Cretaceous of China with scansorial adaptations. Journal
of Vertebrate Paleontology. 34(3), 657-671.
Wang, O'Connor, Pan and Zhou, 2017. A bizarre Early Cretaceous
enantiornithine bird with unique crural feathers and an ornithuromorph
plough-shaped pygostyle. Nature Communications. 8:14141.
Gobipipus Kurochkin, Chatterjee
and Mikhailov, 2013
= "Gobipipus" Mourer-Chauvire, 1995
G. reshetovi Kurochkin, Chatterjee and Mikhailov, 2013
= "Gobipipus reshetovi" Mourer-Chauvire, 1995
Late Campanian, Late Cretaceous
Khermeen Tsav, Baruungoyot Formation, Mongolia
Holotype-
(PIN 4492-3) (embryo) partial skull (16 mm), mandible, seven cervical
vertebrae, four anterior dorsal vertebrae, scapulae (9 mm), coracoids
(6 mm), clavicle, sternum, humeri (13 mm), radii (14 mm), ulna (15 mm),
scapholunare, pisiform, carpometacarpus (7.2 mm), phalanx I-1, phalanx
II-1
Paratypes- (PIN 4492-4) (embryo) verteabrae, ilium (7 mm), (?)pubis (6
mm), femur (9 mm), tibia (13 mm), fibula (12 mm), eggshell
numerous eggs (30-36 x 20-24 mm)
Diagnosis- (after Kurochkin et al., 2013) toothless; upturned rostrum;
maxilla forms an inner and lower flange of the external naris; anterior part
of mesethmoid has a ventral flange within antorbital fenestra; lateral surface
of dentary shows deep horizontal groove posteriorly and two rows of vascular
pits anteriorly; mandibular symphysis; acromial process of scapula has medioventral
projection for procoracoid process; preserved manual phalangeal formula is 1-1-0,
with digit 1 much longer than digit 2.
Comments- Several embryos were described by Elzanowski (1981) and tentatively
referred to Gobipteryx minuta. Chatterjee and Kurochkin (1994) and Kurochkin
(1995, 1996) separated ZPAL MgR-I/33 and two new specimens in the PIN collections
from ZPAL MgR-I/34 as a new taxon of palaeognath. This was to be described in
Nature by Chatterjee, Kurochkin and Mikhailov as "Gobipipus reshetovi"
(Mourer-Chauvire, 1995). Indeed, such a reference is cited as a manuscript by
Kurochkin (1996) and Starck and Ricklefs (1998) and "in press" in
Nature by Kurochkin (1995). The name "Gobipipus reshetovi" was published
by Mourer-Chauvire (1995) and later by Chatterjee (1997), though only as nomina
nuda. Ford (www.paleofile.com) lists "Gobipipus elzanowskii" as a
nomen nudum ascribed to Chatterjee in 1994, though the 'Chatterjee, 1994' entry
in his bibliography is a miscitation of Chatterjee and Kurochkin, 1994. That
species name has not been published to my knowledge. By 2000, Kurochkin (2000,
2004) no longer believed the PIN specimens and ZPAL-MgR-I/33 were a separate
taxon from the enantiornithine specimens. The differences were ascribed to ontogeny.
Kurochkin (2000, 2004) felt these embryos were a new taxon of enantiornithine
which could be distinguished from Gobipteryx based on several characteristics.
The official description was finally published in 2013 by Kurochkin et al. after
Kurochkin's death, though only the PIN specimens were now referred to the new
taxon, with the rest being retained in Gobipteryx. Kurochkin et al. include
Gobipipus in a version of Clarke's analysis and find it to be a basal
enantiornithine.
The eggs have been named Gobioolithus minor and are laevisoolithid (Mikhailov,
1996).
References- Elzanowski, 1981. Embryonic bird skeletons from the Late
Cretaceous of Mongolia. Palaeontologica Polonica. 42, 147-176.
Chatterjee and Kurochkin, 1994. An new embryonic bird from the Cretaceous of
Mongolia. Journal of Vertebrate Paleontology. 14(3), 20A.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut Senckenberg. 181, 37-53.
Kurochkin, 1995. Synopsis of Mesozoic birds and early evolution of Class Aves.
Archaeopteryx. 13, 47-66.
Mourer-Chauvir�, 1995. Society of Avian Paleontology and Evolution. Information
Newsletter.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Mikhailov, 1996. The eggs of birds in the Upper Cretaceous of Mongolia. Paleontologichesky
Zhurnal. 1, 19-121. [in Russian]
Chatterjee, 1997. The Rise of Birds. 312 pp.
Starck and Ricklefs, 1998. Patterns of development: The altricial-precocial
spectrum. in Starck and Ricklefs (eds.). Avian Growth and Development. Evolution
within the altricial precocial spectrum. University Press, New York. pp 3-30.
Kurochkin, 2000. Mesozoic birds of Mongolia and the former USSR. in Benton et
al., eds. The Age of Dinosaurs in Russia and Mongolia. 533-559.
Kurochkin, 2004. The truth about Gobipteryx. Sixth International Meeting
of the Society of Avian Paleontology and Evolution. Abstracts. 33-34.
Kurochkin, Chatterjee and Mikhailov, 2013. An embryonic enantiornithine bird
and associated eggs from the Cretaceous of Mongolia. Paleontological Journal.
47(11), 1252-1269.
Gobipterygiformes Elzanowski, 1974
Gobipterygidae Elzanowski, 1974
Gobipteryx Elzanowski, 1974
G. minuta Elzanowski, 1974
= Nanantius valifanovi Kurochkin, 1996
Late Campanian, Late Cretaceous
Khulsan, Baruungoyot Formation, Mongolia
Holotype- (ZPAL MgR-I/12) (~190 mm) premaxillae, quadrate, vomeral fragment(?),
palatine, partial ectopterygoid, partial pterygoids, mandibles (38 mm), cervical
vertebral fragments
Referred-
(ZPAL MgR-I/32) premaxillae, maxillae, nasal fragment, partial vomer, palatine,
partial pterygoids, dentaries, surangular, angular (Elzanowski, 1976)
Late Campanian, Late Cretaceous
Khermeen Tsav, Baruungoyot Formation, Mongolia
?(PIN 4492-1; holotype of Nanantius valifanovi) (~175
mm) anterior premaxillae, frontals, pterygoids, parabasisphenoid, anterior dentaries,
axis (6.2 mm), seven incomplete cervical vertebrae (5.2 mm), incomplete anterior
dorsal vertebra, sacrum (15 mm), four caudal vertebrae, pygostyle (8.6 mm),
proximal scapula, partial coracoids (~30.8 mm), partial furcula, incomplete
humeri (~44 mm), incomplete radius (~43 mm), incomplete ulnae (~57 mm), distal
metacarpal II, phalanx II-1 (11.3 mm), distal metatarsal III, phalanx III-1
(4.3 mm), partial ilia, distal pubes, partial femur (~36 mm), femoral fragment,
incomplete tibiotarsus (~59.9 mm), tibiotarsal fragments, incomplete fibulae,
metatarsal I (4.1 mm), proximal phalanx I-1, pedal ungual I (8 mm), incomplete
tarsometatarsi (metatarsal II 24.1 mm, metatarsal III 25 mm, metatarsal IV 23.7
mm), proximal phalanx II-1, phalanx II-2, pedal ungual II (8.5 mm), phalanx
III-1, proximal phalanx III-2, distal phalanx III-3, pedal ungual III (7.8 mm),
pedal digit IV phalanges, pedal ungual IV (7.6 mm), thirty eggshell fragments
(Kurochkin, 1996)
(ZPAL MgR-I/33) (embryo) (skull ~20 mm) premaxillae, maxilla, nasals, frontal,
squamosal, quadrate, ectethmoid, exoccipital, basioccipital, posterior mandibular
fragment, atlas(?), anterior cervical neural arch, eighth cervical neural arch,
ninth cervical neural arch, fragmentary tenth cervical neural arch, several
cervical centra, eleventh dorsal neural arch, twelfth dorsal neural arch, first
dorsal neural arch, second dorsal neural arch, third dorsal neural arch, fourth
dorsal neural arch, fifth dorsal neural arch, sixth dorsal neural arch, seventh
dorsal neural arch, four dorsal rib fragments, scapulae (11 mm), coracoid fragments,
incomplete humeri (14 mm), incomplete radius (15.9 mm), incomplete ulna (16.1
mm), metacarpal II, metacarpal III (7.5 mm), distal femur, proximal tibia, pedal
phalanx, pedal ungual, eggshells (Elzanowski, 1981)
(ZPAL MgR-I/34) (embryo) quadrate fragment, pterygoid fragment, parabasisphenoid,
braincase fragments, mandibular fragment, atlas, axis, third cervical vertebra,
fourth cervical vertebra (1.3 mm), fifth cervical vertebra (1.3 mm), sixth cervical
vertebra, seventh cervical vertebra (1.7 mm), eighth cervical vertebra (1.7
mm), ninth cervical vertebra, tenth cervical vertebra, eleventh cervical vertebra,
twelfth cervical vertebra (1.3 mm), first dorsal vertebra (1.3 mm), second dorsal
vertebra (1.6 mm), third dorsal neural arch fragment, five anterior dorsal ribs,
incomplete scapulae, coracoids, partial furcula, proximal humeri (~18.7 mm),
distal radius, distal ulna, pisiform, distal carpals, phalanx I-1 (~2.6 mm), manual
ungual I (~1.3 mm), metacarpal II (11.1 mm), metacarpal III (11.8 mm), eggshells
(Elzanowski, 1981)
(ZPAL MgR-I/88) (embryo) (skull ~88 mm) premaxillae, maxillae, nasal, frontal,
ectethmoid, anterior mandibles, penultimate pedal phalanx (3.6 mm), pedal ungual
(3.3 mm), eggshells (Elzanowski, 1981)
(ZPAL MgR-I/89) (embryo) three dorsal neural arches, fragmentary humerus(?),
fragmentary radius(?), fragmentary ulna(?), metacarpal II, metacarpal III, eggshells
(Elzanowski, 1981)
(ZPAL MgR-I/90) (embryo) fragmentary tibia(?), pedal ungual, eggshells (Elzanowski,
1981)
(ZPAL MgR-I/91) (embryo) posterior skull fragment, fragmentary humerus, fragmentary
radius, fragmentary ulna, fragmentary metacarpal II, fragmentary metacarpal
III, eggshells (Elzanowski, 1981)
(ZPAL MgR-I/92) (embryo) fragmentary coracoid(?), fragmentary humerus(?), fragmentary
metacarpal II, two pedal phalanges, eggshells (Elzanowski, 1981)
Late Campanian, Late Cretaceous
Ukhaa Tolgod, Djadokhta Formation, Mongolia
?(IGM 100/1011) premaxillae, maxillae, partial nasals, vomer, palatines, pterygoid,
ectethmoid, nine sclerotic ossicles, anterior dentary (Chiappe, Norell and Clark,
2001)
Comments- While Chiappe et al. (2001) synonymized Nanantius valifanovi
with Gobipteryx minuta, Kurochkin (2004) kept them separate and referred
IGM 100/1011 to a new species of Nanantius instead of G. minuta.
This was based on an unpublished character analysis, with only a few supposedly
distinguishing characters listed. N. valifanovi was said to differ from
Gobipteryx in the thin and sharp tomium, dorsal premaxillary groove,
and absence of a ventral symphyseal crest on the dentary. Kurochkin et al. (2013)
later kept the two synonymized, though this was published after Kurochkin's
death so may be Mikhailov's opinion instead.
The eggshells associated with PIN 4492-1 have been assigned to the ootaxon Subtilioolithus
multituberculatus in the Laevisoolithidae by Mikhailov (1996).
Several embryos were described by Elzanowski (1981), tentatively referred to
Gobipteryx minuta because of several cranial features. Martin (1983,
1995) and Elzanowski (1995) followed this assignment.
References- Elzanowski, 1974. Preliminary note on the palaeonathous bird
from the Upper Cretaceous of Mongolia. Results of the Polish-Mongolian Paleontological
Expeditions - Part V. Palaeontologica Polonica. 30, 103-109.
Elzanowski, 1976. Palaeognathous bird from the Cretaceous of central Asia. Nature.
264, 51-53.
Elzanowski, 1977. Skulls of Gobipteryx (Aves) from the Upper Cretaceous
of Mongolia. Results of the Polish-Mongolian Paleontological Expeditions - Part
VII. Palaeontologica Polonica. 37, 153-165.
Elzanowski, 1981. Embryonic bird skeletons from the Late Cretaceous of Mongolia.
Palaeontologica Polonica. 42, 147-176.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut Senckenberg. 181, 37-53.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Mikhailov, 1996. The eggs of birds in the Upper Cretaceous of Mongolia. Paleontologichesky
Zhurnal. 1, 19-121. [in Russian]
Chiappe, Norell and Clark, 2001. A new skull of Gobipteryx minuta (Aves:
Enantiornithes) from the Cretaceous of the Gobi Desert. American Museum Novitates.
3346, 1-15.
Kurochkin, 2004. The truth about Gobipteryx. Sixth International Meeting
of the Society of Avian Paleontology and Evolution. Abstracts. 33-34.
Kurochkin, Chatterjee and Mikhailov, 2013. An embryonic enantiornithine bird
and associated eggs from the Cretaceous of Mongolia. Paleontological Journal.
47(11), 1252-1269.
Gretcheniao Chiappe, Meng, Serrano, Sigurdsen, Wang, Bell and Liu, 2019
G. sinensis Chiappe, Meng, Serrano, Sigurdsen, Wang, Bell and Liu, 2019
Barremian-Aptian, Early Cretaceous
Huludao, Yixian Formation, Liaoning, China
Holotype- (BMNHC Ph 829) (236 g)
incomplete skull, mandibles, hyoid, eight cervical vertebrae, elven
dorsal vertebrae, partial dorsal ribs, synsacrum, five acuadl
vertebrae, pygostyle (~20.6 mm), two chevrons, scapulae (~36.8 mm),
coracoids (29.3, 29.3 mm), furcula, sternum, humeri (49.7, ~50.0 mm),
radii (49.2 mm), ulnae (52.9 mm), scapholunares, pisiform,
carpometacarpi (27.9 mm), phalanges I-1 (~11.2, ~9.7 mm), manual ungual
I (~4.9 mm), phalanx II-1 (12.3 mm), phalanx II-2 (7.4 mm), manual
ungual II, phalanx III-1 (6.6 mm), phalanx III-2?, ilia, pubes (38.8,
~35.9 mm), ischia, femora (41.1, 43.2 mm), tibiotarsi (49.6, 50.6 mm),
fibulae, metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi
(26.9 mm), phalanx II-1, phalanges II-2, pedal ungual II, phalanges
III-1, phalanges III-2, phalanx III-3, pedal ungual III, phalanx IV-1,
phalanges IV-2, phalanx IV-3, phalanges IV-4, pedal ungual IV, pedal
claw sheaths, feathers
Diagnosis- (after Chiappe et
al., 2019) slightly tapered omal ends of the furcular rami; ventral
tubercle at the convergence of the furcular rami; slender coracoid with
a sternal margin that is slightly more than 1/3 the length of the bone;
coracoid with straight lateral margin; humeral bicipital area scarred
by a large cranioventrally facing fossa; significantly elongated
carpometacarpus; metacarpal II carrying a protuberance on its dorsal
surface.
Comments- Gretcheniao
was discovered prior to March 2019. Chiappe et al. (2019) state
"there is only a single phalanx of the minor digit" but their figure 7C
illustrates an impression of phalanx III-2. The photograph itself
shows what could be the impression, or could be an artifact in the
sediment.
Chiappe et al. added Gretcheniao to Chiappe's avialan analysis and
recovered it closer to avisaurids and 'bohaiornithids' than to
longipterygids, closest to Junornis.
Reference- Chiappe, Meng, Serrano, Sigurdsen, Wang, Bell and Liu, 2019. New Bohaiornis-like bird from the Early Cretaceous of China: Enantiornithine interrelationships and flight performance. PeerJ. 7:e7846.
Hebeiornis Yan vide Xu,
Yang and Deng, 1999
= Vescornis Zhang, Ericson and Zhou, 2004
H. fengningensis Yan vide Xu, Yang and Deng, 1999
= Vescornis hebeiensis Zhang, Ericson and Zhou, 2004
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China
Holotype- (NIGP 130722) (125 mm; 50 g, subadult) skull, mandibles, hyoid,
atlas, axis, third cervical vertebra, fourth cervical vertebra, fifth cervical
vertebra, sixth cervical vertebra, seventh cervical vertebra, eighth cervical
vertebra, ninth cervical vertebra, several dorsal vertebrae, dorsal ribs, gastralia,
sacrum, pygostyle (10.72 mm), scapulae (13 mm), coracoids, furcula, sternum, sternal ribs,
humeri (25 mm), radii, ulnae (30 mm), scapholunares, pisiforms, metacarpal I, phalanx
I-1, manual ungual I, carpometacarpus, phalanx II-1, phalanx II-2, manual ungual
II, phalanx III-1, partial ilium, partial pubes, incomplete ischium, femora
(25 mm), tibiotarsi (30 mm), proximal tarsals, metatarsal I, phalanx I-1, pedal
ungual I, tarsometatarsi (16.00 mm), phalanx II-1, phalanx II-2, pedal ungual II,
phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1,
phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV
Comments- Jin et al. (2008) reassign Hebeiornis' horizon to the
Qiaotou Member of the Huajiying Formation, as opposed to the Yixian Formation
which was stated in Xu et al. (1999) and Zhang et al. (2004).
This specimen was initially very briefly described in an obscure paper as Hebeiorins
fengningensis (Xu et al., 1999). They list it as gen. et sp. nov. and attribute
it to Yan, 1999, which I assume to mean they are the only author (perhaps a
mispelling of Yang You-shi?) taking credit for the name, as opposed to there
being a separate Yan, 1999 publication that has not been located. The photograph
in Xu et al. is extremely poor, and only labeled "Bird fossils in the bottom
of the Jurassic Yixian Formation". However, only one Yixian bird specimen
is described there, and the pose described for Hebeiornis is the same
(complete specimen exposed ventrally, neck curving to its left). In 2006, Mortimer
(DML) realized it was a photograph of the holotype of Vescornis hebeiensis,
which was described in detail by Zhang et al. (2004). The latter taxon was also
thought to be from the Yixian Formation of Senjitsu in Fengning County, though
that horizon has recently been changed (see above). The measurements match fairly
well with Vescornis (skull ~24 vs. 27 mm; scapula ~17 vs. 13 mm; humerus
~24 vs. 25 mm; ulna ~25 vs. 30 mm; femur ~24 vs. 25 mm; tibia ~30 vs. 30 mm),
as do the few osteological details with the exception of the pygostyle. As Babelfish
translates, Hebeiornis "does not have the tail synthesis bone",
while Vescornis has a pygostyle. Then again, the authors were apparently
unfamiliar with the numerous basal pygostylians with elongate pygostyles (with
the exception of Cathayornis, which they never discuss, only list), so
perhaps Vescornis' elongate pygostyle was too dissimilar to ornithurine
sensu Gauthier
and de Queiroz pygostyles for them to count it. Jin et al. (2008) confirm they
are the same specimen, though they regard Hebeiornis as a nomen nudum.
More recently, Hebeiornis has become the accepted name, being used in
several of O'Connor's publications.
One issue is that the only time Hebeiornis is used in Xu et al.'s (1999)
paper, it is misspelled Hebeiorins. However, ICZN Article 32.5.1 states
"If there is in the original publication itself, without recourse to any
external source of information, clear evidence of an inadvertent error, such
as a lapsus calami or a copyist's or printer's error, it must be corrected."
Xu et al. say "Hebeiorins fengningensis Yan 1999 (gen et sp nov),
namely Hebei Fengning bird (new genus and new species)." Since the suffix
for "bird" is "-ornis" not "-orins", and the difference
is a simple switching of n and i, that seems to be clear evidence of a lapsus
calami. Even if this were not the case, it would still be correct to use Hebeiornis.
Several publications have since used Hebeiornis, but only one I know
of has used Hebeiorins (Ji et al., 2008). If Hebeiorins was the
correct original spelling, the uses of Hebeiornis would be incorrect
subsequent spellings. These are defined by ICZN Article 33.3 as "any subsequent
spelling of a name different from the correct original spelling, other than
a mandatory change or an emendation". Article 33.3.1 states "when
an incorrect subsequent spelling is in prevailing usage and is attributed to
the publication of the original spelling, the subsequent spelling and attribution
are to be preserved and the spelling is deemed to be a correct original spelling."
Since Hebeiornis is in prevailing usage and attributed to Xu et al.,
it's deemed to be the correct original spelling.
References- Xu, Yang and Deng, 1999. First discovery of Mesozoic bird
fossils in Hebei Province and its significance. Regional Geology of China. 18(4),
444-448.
Zhang, Ericson and Zhou, 2004. Description of a new enantiornithine bird from
the Early Cretaceous of Hebei, northern China. Canadian Journal of Earth Sciences.
41(9), 1097-1107.
Mortimer, DML 2006. https://web.archive.org/web/20160806075437/http://dml.cmnh.org/2006Dec/msg00079.html
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx
and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science
Bulletin. 53(18), 2820-2827.
Wang, O'Connor, Pan and Zhou, 2017. A bizarre Early Cretaceous
enantiornithine bird with unique crural feathers and an ornithuromorph
plough-shaped pygostyle. Nature Communications. 8:14141.
Holbotia Zelenkov and Averianov,
2015
= "Holbotia" Kurochkin, 1982 vide Kurochkin, 1991
= "Kholbotiaka" Kurochkin, 1994
H. ponomarenkoi Zelenkov and Averianov, 2015
= "Holbotia ponomarenkoi" Kurochkin, 1982 vide Kurochkin, 1991
Hauterivian-Barremian, Early Cretaceous
Andaikhudag Formation, Mongolia
Holotype- (PIN 3147-200) (subadult) partial skull, partial mandibles,
cervical neural arch, one or two fragmentary dorsal vertebrae, last dorsal centrum,
partial dorsal ribs, fragmentary synsacrum, incomplete caudal vertebra, furcula,
sternal fragment, four sternal ribs, ?phalanx II-1, incomplete ?phalanx II-2,
fragmentary ilia, pubic fragment, partial ischium, partial femur, tibia (~33
mm), astragalus, calcaneum, distal tarsal, metatarsal I, phalanx I-1, pedal
ungual I, metatarsal II, phalanx II-1, partial phalanx II-2, pedal ungual II,
metatarsal III, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III,
metatarsal IV, phalanx IV-1/2/3 fragments, partial phalanx IV-4, pedal ungual
IV, pedal claw sheaths, body feathers
Diagnosis- (after Zelenkov and Averianov, 2015) prenarial portion of
premaxilla low with subparallel dorsal and ventral margins; dentary with widely
spaced, small teeth; at least one cervical vertebra with most anterior part
of prezygapophyseal articular surface facing ventrally; posterior surface of
distal tibia with laterally located robust crest; metatarsus at least eight
times longer than wide proximally.
Comments- Fragmentary manual elements were identified as distal metacarpals
II and III and an incomplete II-1 by Zelenkov and Averianov (2015), but in my
opinion the supposed metacarpals look more similar to a broken II-1, with the
supposed II-1 being II-2. The authors stated "poor preservation of this
area precludes equivocal interpretation of these bone fragments", which
I agree with.
The specimen was discovered in 1977 and initially identified as a bird by Kurochkin
(1979) before he misidentified it as a pterosaur. It was first published by
Kurochkin (1991), who included a photo of the specimen with the caption "Part
of the skeleton of a tiny pterosaur (Mongolia). Bone surrounded [by] convert
organic matter to the side [that] shows two fingerprint feathers. Original."
Next to the slab in the photo is a card with "Holbotia ponomarenkoi Kurochkin,
1982" written on it. Kurochkin (1993) later reidentified the specimen as
a bird in his thesis, as did Unwin (1993). Unwin was the first author to publish
the name Holbotia ponomarenkoi in text, and identified it as probably
ambiortid and possibly Ambiortus, though further study has shown this
to be untrue (Kurochkin, 1995a; etc.). Kurochkin (1994) mentions the Early Cretaceous
"Mongolian Kholbotiaka" as an enantiornithine, but this is a literal
translation from Cyrillic and not a newly proposed genus name. Kurochkin (1995a,
b; 1996; 2000) and Bakhurina and Unwin (1995) provided further details of Holbotia
as an enantiornithine similar to other Early Cretaceous taxa. Note however,
that Bakhurina and Unwin were incorrect in stating Holbotia has subequal
tarsometatarsus and tibiotarsus (actual ratio ~68%) and penultimate pedal phalanges
"no longer than any of the preceding phalanges" (at least phalanx
III-3 is longer than III-2). Also contra Kurochkin (1996), no coracoid is preserved.
More recently, Zelenkov and Averianov (2014) discuss the specimen in an abstract,
misspelling the genus as 'Holobotia'. The official description appeared the
following year, with Zelenkov and Averianov (2015) finding Holbotia to
be most closely related to Neuquenornis, Concornis and Qiliania
using O'Connor's bird matrix.
References- Kurochkin, 1979. Fossil avifauna of Mongolia. Basic results
of the Joint Soviet-Mongolian Palaeontological Expedition for 1969-1969. Palaeontological
Institute, Moscow. 9-10.
Kurochkin, 1991. Protoavis, Ambiortus, and other palaeornithological
rarities. Priroda. 1991(12), 43-53 [In Russian].
Kurochkin, 1993. [The principle stages in evolution of class Aves]. Thesis,
Palaeontological Institute, RAS, Moscow. 64 pp.
Unwin, 1993. Chapter 40. Aves. In Benton (ed.). The Fossil Record 2. Chapman
and Hall, NY. 717-738.
Kurochkin, 1994. Synopsis and Evolution of Mesozoic Birds. Journal F�r
Ornithologie. 135.
Bakhurina and Unwin, 1995. Survey of pterosaurs from the Jurassic and Cretaceous
of the former Soviet Union and Mongolia. Historical Biology. 10, 197-245.
Kurochkin, 1995a. Synopsis of Mesozoic Birds and Early Evolution of Class Aves.
Archaeopteryx. 13, 47-66.
Kurochkin, 1995b. The assemblage of the Cretaceous birds in Asia. in Sun and
Wang (eds.). Sixth Symposium on Mesozoic Terrestrial Ecosystems and Biota, Short
Papers. 203-208.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Kurochkin, 2000. Mesozoic birds of Mongolia and the former USSR. In Benton,
Shishkin, Unwin and Kurochkin (eds.). The Age of Dinosaurs in Russia and Mongolia.
533-559.
Zelenkov and Averianov, 2014. A historical specimen of enantiornithine bird
from the Early Cretaceous of Mongolia. 4th International Paleontological Congress,
Abstract Volume. 148.
Zelenkov and Averianov, 2015. A historical specimen of enantiornithine bird
from the Early Cretaceous of Mongolia representing a new taxon with a specialized
neck morphology. Journal of Systematic Palaeontology. DOI:10.1080/14772019.2015.1051146
Houornis Wang
and Liu, 2015
= "Similicathayornis" Wang and Liu, 2015 online
H. caudatus (Hou, 1997) Wang and Liu, 2015
= Cathayornis caudatus Hou, 1997
= "Similicaudipteryx" caudatus (Hou, 1997) Wang and Liu, 2015 online
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V10917) incomplete skull (26.4 mm), partial mandibles
(~21 mm), gastralia, four caudal vertebrae, partial pygostyle, partial ?coracoid,
incomplete sternum (21.5 mm), humeri (one partial; 25.5 mm), radii (~25 mm),
ulnae (~26.5 mm), pisiform, carpometacarpi (II 12.2, III 12.7 mm), phalanx II-1
(6.9 mm), phalanx II-2 (4.3 mm), manual ungual II (1.7 mm), phalanx III-1 (3.4
mm), pubes (one partial), femora (one partial; ~22.9 mm), tibiotarsi (28.5 mm),
fibula (~7 mm), metatarsals I, phalanges I-1, pedal ungual I (5 mm), tarsometatarsi
(II 14.2, III 15.6, IV 14.8 mm), phalanx II-1, phalanx II-2, pedal unguals II,
phalanx III-1, phalanx III-2, phalanx III-3, pedal unguals III, phalanx IV-4,
pedal unguals IV, five pedal phalanges, pedal claw sheaths
Paratypes- (IVPP V10533) synsacrum (15.5 mm), several caudal vertebrae,
pygostyle, ilia (13 mm), pubes (one partial), femora (one partial; 24.5 mm),
tibiotarsi (30.5 mm), fibulae (9 mm), tarsometatarsi (16 mm), pedal phalanges,
pedal unguals (5 mm), seeds?
?(IVPP V10904) gastralia, tibiotarsi (34.5 mm), fibula, tarsometatarsi (19 mm),
pedal phalanges, pedal unguals (8 mm)
Diagnosis- (after Wang and Liu, 2016) pygostyle longer than tarsometatarsus;
sternum with anterior spine and concave costal margin; posterolateral process
with large fan-shaped distal expansion; pubic peduncle of ilium well developed
and approaching ischiadic peduncle in length; pubic peduncle strongly posteriorly
directed; postacetabular process weakly curved ventrally; distal ends of metatarsals
II and III deflected medially; metatarsal IV trochlea less than half width metatarsal
III trochlea.
Other diagnoses- Hou (1997) included several characters in caudatus'
diagnosis which are problematic. The supposed transverse trough lying between
the frontal and parietal is either an area where the bone has broken away or
due to disarticulation of those elements. A minimum of three pairs of dentary
teeth, "relatively well developed" sternal carina, and elongated tarsometatarsus
that exceeds half tibiotarsal length are true of most enantiornithines. Hou's
interpretation of the caudal vertebrae as unfused is due to misidentifying the
partial left femur as the caudal series, as detailed by Wang and Liu (2016).
Comments- The holotype was discovered in 1993 and described by Hou (1997)
as a new species of Cathayornis based on numerous symplesiomorphies.
O'Connor and Dyke (2010) identified the pygostyle, viewing Hou's supposed string
of unfused caudal vertebrae as the left pubis. They considered the species a
nomen dubium pending further study. Wang and Liu (2016) performed that study,
finding caudatus to be valid though not necessarily closely related to
Cathayornis. Thus they placed it in a new genus Houornis. Their
redescription could not verify the presence of dorsal vertebrae, sacral vertebrae
or scapula, and found the supposed caudal series was actually the left femur.
The supplementary information includes a NEXUS file with the OTU "Similicaudipteryx
caudatus", seemingly an earlier idea for the genus name. Their figured
cladogram does not place Houornis more precisely than Enantiornithes
more derived that Protopteryx and Iberomesornis, and excluded
from derived longipterygids and bohaiornithids, though this may be due to including
the fragmentary Parvavis and OFMB-3. Wang and Liu confirmed the referral
of IVPP V10533 to Houornis based on tarsometatarsal characters, but they
did not mention IVPP V10904 which was also referred to the taxon by Hou. While
the deflection of metatarsal III is ambiguous in Hou's figure, metatarsal IV
does seem to be comparably narrow. It is provisionally retained as Houornis
here pending further study.
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
O'Connor and Dyke, 2010. A reassessment of Sinornis santensis and Cathayornis
yandica (Aves: Enantiornithes). Records of the Australian Museum. 62, 7-20.
Wang and Liu, 2016 (online 2015). Taxonomical reappraisal of Cathayornithidae (Aves: Enantiornithes).
Journal of Systematic Palaeontology. 14(1), 29-47.
Jibeiniaithiformes Zhou and Wang, 2010
"Jibeiniaithidae" Zhou and Wang, 2010
Comments- "Jibeiniaithidae" is
formed incorrectly, as it should be 'Jibeiniidae'. However, it is
also a nomen nudum as it is not "accompanied by a description or
definition that states in words characters that are purported to
differentiate the taxon" (ICZN Article 13.1.1).
Jibeiniaithiformes is also formed incorrectly (should be
'Jibeiniiformes'), but orders are not covered by the ICZN.
Reference- Zhou and Wang, 2010.
Vertebrate diversity of the Jehol Biota as compared with other
lagerst�tten. Science China Earth Sciences. 53(12), 1894-1907.
Jibeinia Hou, 2000
= "Jibeinia" Hou, 1997
J. luanhera Hou, 2000
= "Jibeinia luanhera" Hou, 1997
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China
Holotype- (IVPP collection; lost) (juvenile) partial skull, mandible
(22 mm), six cervical vertebrae (~2.4 mm), five dorsal vertebrae (~2.9 m), dorsal
ribs, gastralia, sacrum, six caudal vertebrae, pygostyle (13 mm), scapula (20
mm), coracoids (11.5 mm), incomplete furcula, sternum (17 mm), humerus (23.3
mm), radius (24.2 mm), ulna (24 mm), semilunate carpal, pisiform, metacarpal I
(2 mm), phalanx I-1 (4 mm), manual ungual I (2.5 mm), metacarpal II (9.3 mm),
phalanx II-1 (6 mm), phalanx II-2 (3.7 mm), manual ungual II (2.1 mm), metacarpal
III (8.3 mm), phalanx III-1 (1.5 mm), phalanx III-2 (2.9 mm), manual ungual
III (1 mm), partial ilium, pubis (21 mm), partial ischium, femora (22.2 mm),
tibiae (28 mm), astragali, calcanea, distal tarsal, metatarsal I, phalanx I-1,
pedal ungual I, metatarsal II, phalanx II-1, phalanx II-2, pedal ungual II,
metatarsal III (16.3 mm), phalanx III-1, phalanx III-2, proximal phalanx III-3,
pedal ungual III, metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx
IV-4, pedal ungual IV, feather impressions
Diagnosis- narrow furcular branches; metacarpal II does not extend past
metacarpal II (?); three phalanges on manual digit III (?); trochlea of metatarsal
II not wider than that of metatarsal III (?).
Other diagnoses- Of the diagnostic characters listed by Hou (1997), most
are symplesiomorphic for enantiornithines (numerous unserrated maxillary teeth;
large, broad sternum; reduced manual digit III; fused pubic symphysis; metatarsals
partially fused proximally and unfused distally; metatarsal II shorter than
metatarsal III or IV) or ambiguous (extremely concave cervical centra; unexpanded
distal pubes). The narrow posteromedian sternal process is present in almost
all enantiornithines as derived as Longipteryx, while the final character
(poorly developed posterolateral sternal processes) is problematic. The distal
end of the right process is covered by another element, while the right process
has a broader base which may be the remains of a large distal expansion. If
the right side is more accurate, it would resemble Hebeiornis, while
the left side could resemble Eoenantiornis. Another possibility is that
the sternum is similar to Cathayornis in possessing a small anterolateral
process on the right side, with most of the posterolateral process broken off.
Interestingly, if manual phalanx III-1 is actually a broken piece of metacarpal
III, both the apparently short metacarpal III and presence of three phalanges
on that digit would be resolved and the manus would resemble those of other
enantiornithines. Hou previously claims Confuciusornis has five phalanges
on manual digit III in the same book (again probably due to a broken element),
so such a mistake by him would not be unheard of. It would still have two phalanges
on the digit however, which would be like basal enantiornithines but unlike
some derived taxa.
Comments- The name "Jibeinia luanhera" was first used in Hou
(1997), but only in the captions of three illustrations. In the text, it was
merely called Ji Bei bird (this is untrue in the English translation). Because
the scientific name was not given in the text itself, "Jibeinia" was
a nomen nudum. Later, Hou (2000) used the scientific name in the text of his
semipopular Picture Book of Chinese Fossil Birds, with accompanying illustrations
and disgnosis. This counts as the first official use of the name. Unfortunately,
neither work contains trustworthy descriptions or accurate illustrations. The
illustrations in Hou (1997) are hopelessly schematic, while the skeletal reconstructions
in Hou (2000) aren't respresentative of bird anatomy, let alone that of Jibeinia
itself. Hou's (1997) descriptions contain features not known in birds (e.g.
septomaxillae, presternae) as well as numerous characters which clash with those
described in more recent and better illustrated papers (e.g. Confuciusornis
in Chiappe et al., 1999). In addition, the holotype is presently lost (Hou pers.
comm., 2001 to Zhang et al., 2004) and existing casts are of low quality. Thus
all morphological details of Jibeinia are suspect, except the few which
can be gleaned from published photographs.
Jin et al. (2008) reassign Jibeinia's horizon to the Qiaotou Member of
the Huajiying Formation, as opposed to the Yixian Formation which was stated
in Hou (1997) and Zhang et al. (2004).
Based on comparison with undoubted juvenile enantiornithines (Dalingheornis,
Liaoxiornis, GMV 2158, GMV 2159, etc.), Jibeinia is near certainly
a juvenile as well. Characters supporting this conclusion include- unfused sacrum;
sternal keel absent; high interclavicular angle; humeral head not concave proximally;
humeral distal condyles undeveloped, which in turn causes the ventral condyle
to not project distally; carpometacarpus fusion absent; pelvic fusion absent;
cnemial crest absent; tibiotarsal, proximal tarsal and distal tarsal fusion
absent. Some of these characters are seen in most of the taxa described by Hou
(1997), so may be due to the schematic illustration quality or incorrect description
instead.
Jibeinia exhibits several primitive characters for an ornithothoracine.
It supposedly lacks a sternal keel, has three phalanges on manual digit III,
and a metacarpal I which is unfused to the carpometacarpus. In addition, the
unfused carpometacarpus and pelvis, absent cnemial crest and unfused tibiotarsus
and tarsus are all near certainly juvenile characters, being more primitive
than more basal avebrevicaudans like Sapeornis and Confuciusornis.
However, Jibeinia exhibits a narrower interclavicular angle (~66 degrees)
and less phalanges on manual digit III than confuciusornithids and most more
basal maniraptorans. Because Jibeinia is probably a juvenile, it is unclear
if some characters it possesses are due to being juvenile or being basal. The
posteromedian sternal process is narrow as in enantiornithines, but the ventral
humeral condyle doesn't appear to be distally projected, if the illustration
can be trusted. The latter is the juvenile condition for enantiornithines, however.
Metatarsal IV is reduced in width as in enantiornithines.
Zhang et al. (2004) suggested Jibeinia may be a senior synonym of Hebeiornis
(described by those authors as Vescornis), which they described from
the same formation. This was based on their identical size and numerous similar
characteristics. Besides those characters listed in the diagnosis, Jibeinia
differs from Hebeiornis in- more shallow anterior dentary; elongate posteromedial
sternal processes; narrow ventral tubercle of humerus; larger manual ungual
I. Jibeinia supposedly has amphicoelous cervicals and dorsals, while
Hebeiornis has heterocoelous cervicals and an opisthocoelous dorsal (but
note the comment above regarding enantiornithine central articulations). Besides
the numerous juvenile characters listed above (some of which Hebeiornis
shows as well- unfused sacrum, metacarpal I unfused to carpometacarpus, proximal
tarsals unfused to tibia), Jibeinia is younger based on supposed foramina
between neural arches in the pygostyle, and its undeveloped distal femoral condyles.
Based on comparison to Hebeiornis, the proximal coracoid of Jibeinia
may be broken off, though Hou does describe it as having a rounded head. If
it is complete, it is shorter than in Hebeiornis.
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Hou, 2000. Picture Book of Chinese Fossil Birds. Yunnan Science and Technology
Press, Kunming, China.
Zhang, Ericson and Zhou, 2004. Description of a new enantiornithine bird from
the Early Cretaceous of Hebei, northern China. Canadian Journal of Earth Sciences.
41(9), 1097-1107.
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx
and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science
Bulletin. 53(18), 2820-2827.
Junornis Liu, Chiappe, Serrano, Habib, Zhang and Meng, 2017
J. houi Liu, Chiappe, Serrano, Habib, Zhang and Meng, 2017
Barremian-Aptian, Early Cretaceous
Liutaiogou, Yixian Formation, Inner Mongolia, China
Holotype- (BMNHC Ph 919a, b)
(30.4 g) skull (30.6 mm), mandibles, hyoids, atlas, axis, six or seven
postaxial cervical vertebrae, several dorsal vertebrae, dorsal ribs,
gastralia, synsacrum, seven caudal vertebrae, few chevrons?, pygostyle,
scapulae (20.1 mm), coracoids (14.1 mm), furcula, sternum (18.5 mm),
sternal ribs, humeri (25.9 mm), radii (25.7 mm), ulnae (26.9 mm),
scapholunares, pisiform, carpometacarpi (mcI 1.9, mcII 11.7, mcIII 12.6
mm), phalanges I-1 (4.5 mm), manual unguals I (2.8 mm), phalanges II-1
(5.5 mm), phalanges II-2 (4.1 mm), manual unguals II (2.5 mm),
phalanges III-1 (3.5 mm), phalanges III-2 (1.1 mm), manual claw
sheaths, ilia (~15 mm), pubes (25.5 mm), ischia (~15 mm), femora (23.4
mm), tibiotarsi (28.1 mm), fibulae, metatarsals I, phalanges I-1 (4.3
mm), pedal unguals I (4.8 mm), tarsometatarsi (mtII 15.5, mtIII 16.8,
mtIV 16.1 mm), phalanges II-1 (3.1 mm), phalanges II-2 (4.8 mm), pedal
unguals II (5.1 mm), phalanges III-1 (4.6 mm), phalanges III-2 (4.1
mm), phalanges III-3 (4.5 mm), pedal unguals III (6.1 mm), phalanges
IV-1 (2.8 mm), phalanges IV-2 (2.8 mm), phalanges IV-3 (2.8 mm),
phalanges IV-4 (3.1 mm), pedal unguals IV (5.1 mm), pedal claw sheaths,
body feathers (6-14 mm), remiges (to ~72.7 mm), retrices (~200 mm)
Diagnosis- (after Liu et al.,
2017) costal processes of last two penultimate synsacral vertebrae
three times wider than same process of last synsacral vertebra; rounded
anterolateral corner of sternum (more angular in Cathayornis and Houornis);
distinct trough excavating ventral surface of anteromedial portion of
sternum; triangular process at base of sternal posterolateral process
(absent in Houornis and Eocathayornis); sternal posterolateral process broad (much wider than in Cathayornis, Eocathayornis and Houornis); sternal posterolateral process laterally deflected (straight in Cathayornis and Eocathayornis); sternal posteromedial process nearly level with mid-shaft of posterolateral process (significantly shorter in Cathayornis, Houornis and Eocathayornis); sternal posteromedian process level with posterolateral process (posterolateral processes project further posteriorly in Houornis and Cathayornis); very broad pelvis.
Comments- The holotype was discovered by June 2016. Liu et al. felt it was most similar to Cathayornis, Eocathayornis and Houornis but did not perform a phylogenetioc analysis.
Reference- Liu, Chiappe,
Serrano, Habib, Zhang and Meng, 2017. Flight aerodynamics in
enantiornithines: Information from a new Chinese Early Cretaceous bird.
PLoS ONE. 12(10): e0184637.
Largirostrornis Hou,
1997
L. sexdentoris Hou, 1997
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V10531) (~160 mm) skull (32 mm), partial mandibles, cervical
vertebrae, several dorsal vertebrae, gastralia, sacrum, caudal vertebrae, coracoids
(19 mm), partial furcula, sternum (~22 mm), humerus (31 mm), radius, ulna (~31.5
mm), carpometacarpus (15 mm), manual ungual (2 mm), ilia, pubes, ischia, femora
(28.5 mm), tibiotarsi (33 mm), fibula, tarsometatarsi (19 mm), pedal phalanges,
pedal unguals
Comments- Pittman et al. (2020) listed Largirostrornis as a junior synonym of Cathayornis without comment.
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Pittman, O'Connor, Tse, Makovicky, Field, Ma, Turner, Norell, Pei and
Xu, 2020. The fossil record of Mesozoic and Paleocene pennaraptorans.
In Pittman and Xu (eds.). Pennaraptoran Theropod Dinosaurs: Past
Progress and New Frontiers. Bulletin of the American Museum of Natural
History. 440(1), 37-95.
Liaoxiornithiformes Hou, Zhou, Zhang and Gu, 2002
Liaoxiornithidae Hou, Zhou, Zhang and Gu, 2002
Liaoxiornis Hou and Chen, 1999a
= Lingyuanornis Ji and Ji, 1999
L. delicatus Hou and Chen, 1999a
= Lingyuanornis parvus Ji and Ji, 1999
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (NIGP 130723; GMV-2156 is counterpart and holotype of
Lingyuanornis parvus) (82 mm; juvenile) skull (20.3 mm), mandible (20
mm), ten cervical vertebrae, cervical rib, twelve dorsal vertebrae, twenty-two
dorsal ribs, six sacral vertebrae (11 mm), seven caudal vertebrae (4.1 mm),
pygostyle (16 mm), scapulae (10.1, 10.1 mm), coracoids (7.5 mm), furcula (7.6
mm), sternum (3.2 mm), lateral sternal ossification, humeri (15.5, 15.4 mm),
radii (14.9 mm), ulnae (15.6 mm), scapholunare, pisiform, semilunate carpal, metacarpal
I (1.3 mm), metacarpals II (6.5 mm), manual phalanx II-1 (4.3 mm), metacarpals
III (7.4 mm), phalanx III-1, ilia (9-10 mm), pubes (6.6 mm), femora (14.4, 14.5
mm), tibiae (16.5, 17.1 mm), tarsal, metatarsals I, phalanx I-1, pedal unguals
I, metatarsals II (9.6 mm), phalanges II-1, phalanges II-2, metatarsals III
(10.4 mm), phalanges III-1, phalanx III-2, metatarsals IV (9.6 mm), pedal phalanges,
remiges
Comments- Discovered in 1998 or 1999, the part and counterpart of Liaoxiornis
were obtained by different museums and described as different taxa. Hou and
Chen (1999a,b) of the NIGP (and IVPP) described the part as Liaoxiornis delicatus
in early February 1999 (English version appeared in May). Ji and Ji (1999) of
the GMV described the counterpart as Lingyuanornis parvus in March 1999.
Harris (pers. comm. 2001 to Mortimer (online, 2001) discovered the specimens
were from the same individual, while Creisler (online 2001) determined the nomenclatural
priority. While at least Hou and Chen viewed Liaoxiornis as an adult,
it is clearly a juvenile as confirmed by Chiappe and Ji (2002) and Chiappe et
al. (2007). The latter authors argue the holotype is indeterminate and that
the name Liaoxiornis delicatus "should be abandoned", placing
it in quotes. Yet the taxon is valid under the ICZN and cannot simply be disappeared
regardless of how diagnostic its holotype is. Similarly, O'Connor's (2009) claim
the taxon is a nomen nudum is incorrect, as it was properly established under
ICZN rules.
References- Hou and Chen, 1999a. Liaoxiornis delicatus gen. et
sp. nov., the smallest Mesozoic bird. Kexue Tongbao. 44(3), 311-315.
Hou and Chen, 1999b. Liaoxiornis delicatus gen. et sp. nov., the smallest
Mesozoic bird. Chinese Science Bulletin. 44(9), 834-838.
Ji and Ji, 1999. A new genus of the Mesozoic birds from Lingyuan, Liaoning,
China. Chinese Geology. 262(3), 45-48.
Creisler, online 2001. https://web.archive.org/web/20160806095206/http://dml.cmnh.org/2001Jun/msg00051.html
Mortimer, online 2001. https://web.archive.org/web/20160806121810/http://dml.cmnh.org/2001Jul/msg00344.html
Chiappe and Ji, 2002. Enantiornithine (Aves) neonates from the Early Cretaceous
of China. Journal of Vertebrate Paleontology. 22(3), 43A.
Chiappe and Walker, 2002. Skeletal morphology and systematics of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). In Chiappe and Witmer (eds.).
Mesozoic Birds - Above the Heads of Dinosaurs. University of California Press,
Berkeley, Los Angeles, London. 240-267.
Hou, Zhou, Zhang and Gu, 2002. Mesozoic birds from Western Liaoning in China.
ISBN 7-5381-3392-5. 120 pp.
Chiappe, Ji and Ji, 2007. Juvenile birds from the Early Cretaceous of China:
Implications for enantiornithine ontogeny. American Museum Novitates. 3594,
46 pp.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
Linyiornis Wang, Wang, O'Connor,
Wang, Zheng and Zhang, 2016
L. amoena Wang, Wang, O'Connor, Wang, Zheng and Zhang, 2016
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (STM 11-80; = STM 19-8) (adult female) skull, mandible, ten to twelve cervical
vertebrae fused with ribs, eight to ten dorsal vertebrae, dorsal ribs, synsacrum,
four caudal vertebrae, partial pygostyle, scapulae (38.7 mm), coracoids (25.2
mm), incomplete furcula, fragmentary sternum, humeri (45.2 mm), radii (43.2
mm), ulnae (45.7 mm), radialae, pisiforms, metacarpal I (4.4 mm), phalanges I-1,
carpometacarpi (one partial; 19.7 mm), phalanx II-1, phalanx II-2, manual ungual
II, phalangeal fragments?, ilia (36.1 mm), pubes (one partial; 47 mm), ischium
(19.4 mm), femora (39.7 mm), tibiotarsi (48.3 mm), fibula, metatarsal I, phalanx
I-1, pedal ungual I, tarsometatarsi (mtII 21.2, mtIII 23.4, mtIV 22 mm), phalanges
II-1, phalanges II-2 (one partial), pedal ungual II, phalanges III-1, phalanges
II-2 (one partial), phalanx III-3, pedal unguals III, phalanges IV-1, phalanx
IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal phalanges, seven ovarian
follicles (5.6-7.1 mm)
Diagnosis- (after Wang et al., 2016) rostrum with dorsoventral height
of premaxillary body equal to its anteroposterior length; scapular shaft sagittally
curved with blunt distal end; bicipital crest hypertrophied with strong cranial
projection relative to humeral shaft; muscle attachment pit massive and craniodistally
located on bicipital crest; fossa for capital ligament distinctly absent from
femoral head.
Comments-
The specimen was discovered prior to 2015. Wang et al. (2016a) found
this to be a bohaiornithid using O'Connor's bird matrix. Notably, Wang
et al. (2016b) later in a paper describing what would be named Piscivorenantiornis added the OTU STM19-8 to O'Connor's matrix which they referenced as referring to Linyiornis. The scores are identical, so whether STM 19-8 was a typo or the specimen changed numbers is uncertain.
Reference- Wang, Zhou and Sullivan, 2016b. A fish-eating enantiornithine bird from
the Early Cretaceous of China provides evidence of modern avian
digestive features. Current Biology. 26, 1170-1176.
Wang, Wang, O'Connor, Wang, Zheng and Zhang, 2016a. A new Jehol
enantiornithine bird with three-dimensional preservation and ovarian follicles.
Journal of Vertebrate Paleontology. 36(2), e1054496.
Martinavis Walker, Buffetaut
and Dyke, 2007
Other diagnoses- Walker et al. (2007) note numerous characters which
they correctly state are shared with other enantiornithines- proximal margin
of humerus concave in its central portion, rising both ventrally and dorsally
on either side; bicipital crest prominent; ventral surface of bicipital crest
bearing a small fossa for muscle attachment; proximally L-shaped humeral head;
well-marked depression underneath the proximal head of the humerus; weakly developed
distal condyles; flat distal end that is not deflected dorsally. They also list
many characters intended to be apomorphies of Martinavis. The pneumotricipital
fossa is no wider in vincei, saltariensis or minor than
Elbretornis, Enantiornis, Gurilynia, Halimornis or Otogornis,
and is narrow in cruzyensis and whetstonei. It is wide in the
American specimen KU-NM-37 though. The lack of a perforated ventral tubercle
is plesiomorphic and also present in such taxa as Halimornis and Eoalulavis.
Most enantiornithine deltopectoral crests could be described as "flat and
broad", while the stated lack of ventral curvature in the crest is difficult
to understand since it projects dorsally in enantiornithines. The lack of a
marked distal angle between the deltopectoral crest and shaft distally is primitive
and also seen in such taxa as Eoalulavis, Eocathayornis, Hebeiornis, Otogornis,
Pengornis and Cathayornis, but is absent in saltariensis and
not determinable in KU-NM-37. The bicipital crest in cruzyensis and vincei
is no smaller than in Gurilynia, while KU-NM-37, minor, saltariensis
and whetstonei have large crests. The bicipital crest is indeed more
anteriorly angled in vincei and KU-NM-37 than Elbretornis, Enantiornis,
Halimornis or Gurilynia, but is less angled than Elsornis.
Supposed Martinavis species minor, saltariensis and whetstonei
have less angled crests. The condition in cruzyensis is not illustrated,
though stated to be less than vincei at least. "Ventral margin of bicipital
crest small" is a confusing statement, and the ventrally placed bicipital
fossa is also present in Elbretornis, Gurilynia and Halimornis
while those of M. cruzyensis, saltariensis and minor are
anteroventrally placed. The ventral condyle is as poorly developed in Elbretornis,
Elsornis, Eocathayornis, Kizylkumavis and Cathayornis. Note neither
this nor the next three characters can be evaluated in minor, whetstonei
or KU-NM-37. Alexornis, Elbretornis, Elsornis, Kizylkumavis and Otogornis
lack both scapulotricipital and humerotricipital grooves as well. The ventral
epicondyle is as large and distally projected in Kizylkumavis and probably
Alexornis. A transversely oriented dorsal condyle is present in almost
all enantiornithines, even Elbretornis (contra Walker and Dyke). Walker
et al. also included a differential diagnosis, though it repeats some characters
of the general diagnosis (anteriorly angled bicipital crest; deltopectoral crest
smoothly angled; transversely oriented dorsal condyle) and has another which
contradicts the general diagnosis (small entepicondyle). Of the remaining characters,
the shaft is actually less gracile than Enantiornis (and most other enantiornithines),
not more. A laterally positioned ectepicondyle is present in all enantiornithines.
Walker and Dyke do not add further characters to the diagnosis.
Comments- Walker et al. (2007) established this genus for several large
humeri from the Late Cretaceous of Argentina (M. vincei, PVL-4025, 4028
and 4046), France (M. cruzyensis) and the US (KU-NM-37). Walker and Dyke
(2009) later named PVL-4025 M. saltariensis, PVL-4028 M. whetstonei
and PVL-4046 M. minor. However, as seen above, none of these specimens
share unique apomorphies. In fact, M. cruzyensis lacks two of the supposed
Martinavis synapomorphies, saltariensis lacks four, both minor
and whetstonei lack at least three, and the American specimen lacks at
least one. Walker and Dyke refer numerous additional postcranial elements to
Martinavis sp. based on size (PVL-4030-4032, 4034, 4036-4038, 4044, 4049,
4056, 4060 and tentatively 4273), but since there's no evidence that genus was
present in Argentina, it seems best to keep these as Enantiornithes indet..
References- Walker, Buffetaut and Dyke, 2007. Large euenantiornithine
birds from the Cretaceous of southern France, North America and Argentina. Geological
Magazine. 144(6), 977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
M. cruzyensis Walker, Buffetaut and Dyke, 2007
Late Campanian-Early Maastrichtian, Late Cretaceous
Massecaps, Herault, France
Holotype- (ACAP-M 1957) humerus (92 mm)
Other diagnoses- Several characters in Walker et al.'s diagnosis are
identical to those for their Martinavis generic diagnosis and are present
in other taxa as noted above- bicipital crest of humerus strongly projected
anteriorly; broad deltopectoral crest; lack of a perforated ventral tubercle;
ventral epicondyle enlarged and extended distally. Of the remaining characters,
the capital groove is also wide in Gurilynia and Eoalulavis and
is also deep in most enantiornithines (except Elsornis; it is actually
said to be deeper in M? vincei). The deltopectoral crest is also deeply
concave posteriorly in M? vincei and Halimornis. The dorsal and
ventral condyles are not enlarged or expanded more than M? vincei, Gurilynia,
Kizylkumavis or Alexornis.
Reference- Walker, Buffetaut and Dyke, 2007. Large euenantiornithine
birds from the Cretaceous of southern France, North America and Argentina. Geological
Magazine. 144(6), 977-986.
Martinavis? minor Walker and Dyke,
2009
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4046) incomplete humerus (~67 mm)
Diagnosis- (after Walker and Dyke, 2009) two-thirds the size of M?
vincei and M? saltariensis; head of its humerus less notched on its
cranial surface; external tuberosity less bulbous in proximal view.
Comments- PVL-4046 was first listed as Enantiornithes by Chiappe (1996),
and later assigned by Walker et al. (2007) to Martinavis sp.. Walker
and Dyke (2009) described it as a new species, Martinavis minor. As noted
in the Martinavis comments though, minor does not share any known
apomorphies with the type species of Martinavis and indeed lacks at least
three of that genus' listed apomorphies. Thus there is no reason to refer minor
to Martinavis at this time.
References- Chiappe, 1996. Late Cretaceous birds of southern South America:
anatomy and systematics of Enantiornithes and Patagopteryx deferrariisi.
Munchner Geowissenschaftliche Abhandlungen (A). 30, 203–244.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Martinavis? saltariensis
Walker and Dyke, 2009
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4025) humerus (95.3 mm)
Diagnosis- (after Walker and Dyke, 2009; compared to other Martinavis
species) bicipital crest less cranially inclined; distal extremity of deltopectoral
crest meets the shaft more abruptly; no depression present in capital groove;
base of pneumatic fossa deeper and broader; internal border of shaft proximal
to this fossa is more gently sloped; small entepicondyle; more laterally positioned
ectepicondyle; more transversely orientated external condyle.
Comments- PVL-4025 is a humerus first photographed as Enantiornithes
by Chiappe (1996), and later illustrated by Chiappe and Walker (2002). Walker
et al. (2007) assigned it to Martinavis sp. and it was later made the
holotype of Martinavis saltariensis by Walker and Dyke (2009). However,
saltariensis does not have some supposed Martinavis characters
listed by Walker et al. (deltopectoral crest merges smoothly into shaft; bicipital
crest small and anteriorly angled; large ventral epicondyle), and there are
no characters which it uniquely shares with M. cruzyensis and/or vincei.
It seems best to keep this species out of Martinavis, and it could be
named as a new genus. Based on size, it may belong to Soroavisaurus.
References- Chiappe, 1996. Late Cretaceous birds of southern South America:
anatomy and systematics of Enantiornithes and Patagopteryx deferrariisi.
Munchner Geowissenschaftliche Abhandlungen (A). 30, 203–244.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Martinavis? vincei Walker, Buffetaut
and Dyke, 2007
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4054) humerus (110 mm)
Paratype- (PVL-4059) distal humerus (~110 mm)
Other diagnoses- The bicipital crest was said to be angled more anteriorly
than in M. cruzyensis, but is even more anteriorly angled in Elsornis.
The capital groove seem equally deep in Enantiornis and probably Eocathayornis.
Finally, the distal condyles do not appear "more distally enlarged"
than in M. cruzyensis.
Comments- PVL-4054 was first illustrated by Walker (1981) and later by
Chiappe and Walker (2002) as Enantiornithes, and described as the holotype of
Martinavis vincei by Walker et al. (2007). Chiappe (1996) listed PVL-4059
as Enantiornithines and it was later made the paratype of M. vincei.
However, as noted the the Other diagnoses of Martinavis, none of Walker
et al.'s supposed apomorphies for that genus are valid. This makes referring
vincei to it problematic and indeed it resembles Gurilynia and
Halimornis more than Martinavis in having a broad pneumotricipital
fossa and ventrally placed bicipital fossa. Based on size, it may belong to
Soroavisaurus.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe, 1996. Late Cretaceous birds of southern South America: anatomy and
systematics of Enantiornithes and Patagopteryx deferrariisi. Munchner
Geowissenschaftliche Abhandlungen (A). 30, 203–244.
Chiappe and Walker, 2002. Skeletal morphology and systematics of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University of
California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Martinavis? whetstonei Walker
and Dyke, 2009
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4028) incomplete humerus (~70 mm)
Diagnosis- (after Walker and Dyke, 2009; compared to other Martinavis
species) two-thirds the size of M? vincei and M? saltariensis;
short deltoid crest; internally positioned pneumatic fossa; less cranially inclined
bicipital crest; more bulbous external tuberosity.
Comments- PVL-4028 was first listed as Enantiornithes by Chiappe (1996),
and later assigned by Walker et al. (2007) to Martinavis sp.. Walker
and Dyke (2009) described it as a new species, Martinavis whetstonei.
As noted in the Martinavis comments though, whetstonei does not
share any known apomorphies with the type species of Martinavis and indeed
lacks at least three of that genus' listed apomorphies. Thus there is no reason
to refer whetstonei to Martinavis at this time.
References- Chiappe, 1996. Late Cretaceous birds of southern South America:
anatomy and systematics of Enantiornithes and Patagopteryx deferrariisi.
Munchner Geowissenschaftliche Abhandlungen (A). 30, 203–244.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Microenantiornis Wei and Li, 2017
M. vulgaris Wei and Li, 2017
Early Albian, Early Cretaceous
Chaoyang, Jiufotang Formation, Liaoning, China
Holotype- (PMOL-AB00171) skull (26.5 mm), mandible, atlas,
axis, at least eight postaxial cervical vertebrae, posterior three
dorsal vertebrae, gastralia, synsacrum, three caudal vertebrae,
pygostyle (11.5 mm), scapulae (15.2 mm), coracoids (13.6 mm), furcula,
sternum, humeri (23.6 mm), radii (23.0 mm), ulnae (23.7 mm),
scapholunares, semilunate carpals, metacarpals I (2.9 mm),
carpometacarpi (mcII 7.9, mcIII 9.8 mm), phalanges II-1 (4.3 mm),
phalanges II-2 (4.9 mm), manual ungual II, phalanges III-1 (~1.5 mm),
incomplete ilium, incomplete pubis, ischium, femora (21.3 mm),
tibiotarsi (26.1 mm), fibulae, metatarsals I (2.9 mm), phalanges I-1
(4.5 mm), pedal unguals I (4.6 mm), tarsometatarsi (mtII 16.6, mtIII
17.7, mtIV 17.2 mm), phalanges II-1 (3.8 mm), phalanges II-2 (4.2 mm),
pedal unguals II (4.7 mm), phalanges III-1 (4.5 mm), phalanges III-2
(3.6 mm), phalanges III-3 (4.9 mm), pedal unguals III (6.2 mm), phalanx
IV-1 (~2.7 mm), phalanges IV-2 (~2.4 mm), phalanges IV-3 (2.1 mm),
phalanges IV-4 (3.3 mm), pedal unguals IV (4.1 mm), remiges?
Diagnosis- (after Wei and Lei,
2017) skull high with short snout, orbit ~29% of skull length; no
dentary teeth; forelimbs and himdlimbs nearly equal in length; ratio of
coracoid length vs. distal width ~2.6; length/width ratio of sternum
~1; anterior margin of sternum rounded; sternal posterolateral
processes not expanded distally; sternal posteromedian process slightly
expanded distally; sternal keel absent.
Comments- This was described by
Wei and Li (2017) as an enantiornithine but the paper has not been
fully translated from Chinese. Most of the supposedly diagnostic
characters are indicative of a young ontogenetic stage (high skull with
large orbit; rounded anterior sternum; small sternal posterolateral
process distal expansions; sternal keel absent), which matches the
incompletely fused carpometacarpi.
Reference- Wei and Li, 2017.
Discovery of a new enantiornithine bird from Lower Cretaceous of
western Liaoning, China. Global Geology. 36(3), 655-662.
Monoenantiornis Hu and
O'Connor, 2016
M. sihedangia Hu and O'Connor, 2016
Early Albian, Early Cretaceous
Sihedang, Jiufotang Formation, Liaoning, China
Holotype- (IVPP V20289) (subadult) incomplete skull, incomplete mandibles,
hyoid, seven cervical vertebrae, six dorsal vertebrae, several dorsal ribs,
uncinate processes, synsacrum, three caudal vertebrae, incomplete pygostyle,
scapulae (one fragmentary; ~37.1 mm), coracoids (24.4 mm), partial furcula,
incomplete sternum, sternal ribs, humeri (45.1 mm), radii (43.3 mm), ulnae (45.6
mm), scapholunares, pisiforms, semilunate carpals, metacarpal I (~5 mm), phalanges
I-1 (7.1 mm), manual unguals I (4.2 mm), metacarpals II (19.2 mm), phalanges
II-1 (one partial; 10.8 mm), phalanges II-2 (one partial; 11.2 mm), manual unguals
II (one partial; 4 mm), metacarpals III (20 mm), phalanx III-1, partial ilia,
pubes, femora (38.5 mm), tibiae (45.5 mm), fibulae, astragalocalcaneum, distal
tarsals III+IV, metatarsal I, phalanx I-1 (6.4 mm), pedal ungual I (9.1 mm),
metatarsals II, phalanges II-1 (5.7 mm), phalanges II-2 (7.9 mm), pedal unguals
II (11.2 mm), metatarsals III, phalanges III-1 (7.5 mm), phalanges III-2 (7.2
mm), phalanges III-3 (6.5 mm), pedal ungual III, metatarsals IV, phalanges IV-1
(4.3 mm), phalanges IV-2 (3 mm), phalanges IV-3 (3.4 mm), phalanges IV-4 (2.4
mm), pedal unguals IV, pedal claw sheaths, body feathers, remiges
Diagnosis- (after Hu and O'Connor, 2016) small teeth with unrecurved
and pointed apices; premaxillary teeth with lingual grooves; sternum with narrowly
vaulted anterior margin; posterolateral sternal processes directed posterolaterally
and terminating anterior to distal end of posteromedian process; furcular articular
surface of scapula large and triangle-shaped; distal half of lateral coracoid
margin strongly convex; extension of metacarpal III beyond metacarpal II >15%
length of the latter; single and low cnemial crest present along proximal 30%;
extremely robust pedal digit II and delicate pedal digit IV.
Comments- While Hu and O'Connor (2016) assigned Monoenantiornis
to the Yixian Formation, it was found in Sihedang, which is here viewed as belonging
to the Jiufotang Formation (see Iteravis entry). Using a verson of O'Connor's
bird matrix, Hu and O'Connor recovered Monoenantiornis as the most basal
enantiornithine more derived than longipterygids.
Reference- Hu and O'Connor, 2016. First species of Enantiornithes from
Sihedang elucidates skeletal development in Early Cretaceous enantiornithines.
Journal of Systematic Palaeontology. http://dx.doi.org/10.1080/14772019.2016.1246111
Musivavis Wang, Cau, Luo, Kundrat, Wu, Ju, Guo, Liu and Ji, 2022
M. amabilis Wang, Cau, Luo, Kundrat, Wu, Ju, Guo, Liu and Ji, 2022
Early Albian, Early Cretaceous
Shangheshou, Jiufotang Formation, Liaoning, China
Holotype- (MHGU-3000)
(subadult) incomplete skull (30 mm), sclerotic plates, mandibles (one
partial), partial hyoid, nine cervical vertebrae, three dorsal
vertebrae, two dorsal ribs, synsacrum (15 mm), few caudal vertebrae,
pygostyle (~12 mm), scapulae (one partial; 26 mm), coracoids (14 mm),
furcula, sternum (15 mm), twelve sternal ribs, humeri (30 mm), radii
(33 mm), ulnae (33 mm), scapholunare, pisiforms, metacarpals I (4 mm),
phalanges I-1 (5 mm), manual unguals I (2 mm), carpometacarpi (mcII 14,
mcIII 16 mm), phalanges II-1 (8 mm), phalanges II-2 (one proximal; 5
mm), manual ungual II (2 mm), phalanges III-1 (4 mm), ilial fragment,
pubes, distal ischium, femora (27 mm), incomplete tibiotarsi (33 mm),
fibulae (~8 mm), metatarsals I (4 mm), phalanges I-1 (5 mm), pedal
unguals I (7 mm), tarsometatarsi (mtII 19, mtIII 19, mtIV 18 mm),
phalanges II-1 (4 mm), phalanges II-2 (4 mm), pedal unguals II (6 mm),
phalanges III-1 (6 mm), phalanges III-2 (5 mm), phalanges III-3 (5 mm),
pedal unguals III (5 mm), phalanges IV-1 (3 mm), phalanx IV-2 (3 mm),
phalanges IV-3 (3 mm), phalanges IV-4 (4 mm), pedal unguals IV (4 mm)
Diagnosis- (after Wang et al., 2022) pygostyle abruptly tapers distally (also in Gretcheniao);
sulcus excavating furcular arms very deep and extends onto the proximal
third of the hypocleideum; sharp keel runs along entire ventral surface
of furcula, from the junction of the epicleideal rami to the distal tip
of the hypocleideum; flat anterior margin of sternum becomes curved
near the anterolateral process; sternum possesses anterolaterally
projected anterolateral processes; posteromedian process of sternum
extends nearly to same level as posterolateral processes and expands as
a blunt distal end (also in Bohaiornis);
manual phalanx I-1 has a transversally expanded proximal end followed
by a gracile shaft, resulting in a concave proximomedial corner of the
bone.
Comments- The holotype "was
discovered around year 2000, and was at least for a decade in the
Museum of Hebei University collection before being studied" (Cau, online 2022).
Wang et al. (2022) used Cau's bird matrix to recover Musivavis as the sister taxon to Dunhuangia in Euenantiornithes.
References- Cau, online 2022. http://theropoda.blogspot.com/2022/02/lamabile-mosaico-di-musivavis.html
Wang, Cau, Luo,
Kundrat, Wu, Ju, Guo, Liu and Ji, 2022. A new bohaiornithid-like
bird from the Lower Cretaceous of China fills a gap in enantiornithine
disparity. Journal of Paleontology. 96(4), 961-976.
Nanantius Molnar, 1986
Diagnosis- (after Kurochkin and Molnar, 1997) laterally convex tibiotarsal
shaft; caudal intercotylar prominence on the proximal tibiotarsal articular
surface; well expressed fibular crest on lateral edge of tibial shaft; oblong
fossae on cranial and caudal sides of the fibular crest.
Comments- The partial skeleton PIN 4492-1 was originally described as
a new species, Nanantius valifanovi (Kurochkin, 1996), but has been identified
as a specimen of Gobipteryx minuta (Chiappe et al., 2001). This limits
known Nanantius specimens to partial tibiotarsi and a vertebra from the
Tollebuc Formation of Queensland.
References- Molnar, 1986. An enantiornithine bird from the Lower Cretaceous
of Queensland, Australia. Nature 322 736-738.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
Kurochkin and Molnar, 1997. New material of enantiornithine birds from the Early
Cretaceous of Australia. Alcheringa. 21, 291-297.
Chiappe, Norell and Clark. 2001. A new skull of Gobipteryx minuta (Aves:
Enantiornithes) from the Cretaceous of the Gobi Desert. American Museum Novitates
3346: 1-15.
N. eos Molnar, 1986
Albian, Early Cretaceous
Toolebuc Formation, Queensland, Australia
Holotype- (QM F12992; lost) (~135 mm) incomplete tibiotarsus (~34 mm)
Referred- ....(QM F12991; lost) cervical vertebra (Kurochkin and Molnar,
1997)
(QM F16811) proximal tibiotarsus (Kear et al., 2003)
Diagnosis- (modified from Kurochkin and Molnar, 1997) lateral cnemial
crest absent; absence of long, low lateral eminence in fossa lateral to lateral
cnemial crest; cranial cnemial crest on the medial edge of the tibiotarsus;
nutrient foramen on caudal side of shaft near termination of fibular crest.
Comments- The cervical vertebra (QM F12991) was found less than 5 cm
from the holotype tibiotarsus, so may belong to the same individual and taxon.
O'Connor (2009) reports both are lost. The proximal tibiotarsus described by
Kear et al. (2003) from ichthyosaur gut contents is more similar to N. eos
than QM F31813 in the absence of a lateral cnemial crest and eminence lateral
to that. It is provisionally assigned to N. eos here based on provenence.
References- Molnar, 1986. An enantiornithine bird from the Lower Cretaceous
of Queensland, Australia. Nature. 322, 736-738.
Kurochkin and Molnar, 1997. New material of enantiornithine birds from the Early
Cretaceous of Australia. Alcheringa. 21, 291-297.
Kear, Boles and Smith, 2003. Unusual gut contents in a Cretaceous ichthyosaur.
Proceedings of the Royal Society of London B. 270, S206-S208.
O'Connor, 2009. A systematic review of Enantiornithes (Aves: Ornithothoraces).
PhD thesis, University of Southern California. 586 pp.
N. sp. nov. (Kurochkin and Molnar, 1997)
Albian, Early Cretaceous
Toolebuc Formation, Queensland, Australia
Material- (QM F31813) proximal tibiotarsus (~28 mm)
Diagnosis- (modified from Kurochkin and Molnar, 1997) lateral cnemial
crest present; long, low lateral eminence in fossa lateral to lateral cnemial
crest; cranial cnemial crest caudal to the medial edge of the tibiotarsus; nutrient
foramen on caudal side of shaft near termination of fibular crest absent.
Reference- Kurochkin and Molnar, 1997. New material of enantiornithine
birds from the Early Cretaceous of Australia. Alcheringa. 21, 291-297.
Otogornis Hou, 1994
O. genghisi Hou, 1994
Early Cretaceous
Jingchuan (not Yijinholuo) Formation, Inner Mongolia, China
Holotype- (IVPP V9607) (~150 mm, 170 g) scapulae (24 mm), coracoids (22
mm), humeri (31 mm), radii (40, 42 mm), ulnae (43, 50.1 mm), partial carpometacarpus,
phalanx I-1(?), manual ungual I(?), feather impressions
Comments- Originally identified as an enantiornithine by Dong (1994),
Hou (1994) later named the specimen and placed it as a basal enantiornithine.
Kurochkin (1999) believed the taxon to be a palaeognath related to Ambiortus
instead, assigning both to the Ambiortiformes.
References- Dong, 1994. A Lower Cretaceous enantiornithine bird from
the Ordos Basin of Inner Mongolia, People's Republic of China. Canadian Journal
of Earth Sciences. 30(10), 2177-2179.
Hou, 1994. A Late Mesozoic bird from Inner Mongolia. Vertebrata PalAsiatica.
32(4), 258-266.
Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park, Lugu Hsiang, Taiwan.
221 pp.
Kurochkin, 1999. The relationships of the Early Cretaceous Ambiortus
and Otogornis (Aves: Ambiortiformes). Smithsonian Contributions to Paleobiology.
89, 275-284.
Paraprotopteryx Zheng,
Zhang and Hou, 2007
P. gracilis Zheng, Zhang and Hou, 2007
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China
Holotype- (STM V001) (subadult) several dorsal vertebrae, partial dorsal
ribs, gastralia, pygostyle (12.9 mm), scapula (17.9 mm), coracoids (12.8 mm),
partial sternum, sternal rib, incomplete humeri (22.6 mm), radii, ulnae (23.5
mm), scapholunares, pisiforms, carpometacarpi (11.5 mm), manual phalanx I-1 (2.9 mm),
manual ungual I, phalanx II-1 (5.5 mm), phalanx II-2 (3.5 mm), manual ungual
II, phalanges III-1 (2.9 mm), phalanx III-2, manual claw sheath, incomplete
femur (22.2 mm), tibiae (one partial; 26.3 mm), astragalocalcanea, metatarsals
I, phalanges I-1, pedal unguals I, tarsometatarsi (15.7 mm), phalanges II-1,
phalanges II-2, pedal unguals II, phalanx III-1, phalanx III-2, phalanx III-3,
pedal ungual III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges
IV-4, pedal unguals IV, remiges, retrices, body feathers
Other diagnoses- Zheng et al. (2007) list numerous additional characters
in their diagnosis. The scapula is no longer (79%) than several other enantiornithines
including the contemporaneous Jibeinia (86%). The elongation of the coracoid
(length 2.37 times distal width, not 2.5 times as listed in the diagnosis) is
very similar to Eoenantiornis (2.34) and in any case is intermediate
between ratios in other enantiornithines. The authors state the furcula has
two distinguishing features- an interclavicular angle of less than 40 degrees
and a highly elongate hypocleideum (three-fourths of clavicular branch length).
However, plate II shows that the supposed clavicular branches of the furcula
are dorsal ribs while the illustrated hypocleidium is nowhere to be found in
the photograph. This would explain the unusually slender clavicular branches
in the illustration. The posteromedial sternal process is said to be longer
and more robust than the posterolateral process, but the photograph indicates
the supposed posterolateral process is probably a sternal rib instead. This
leaves the supposed posteromedial process as the posterolateral process while
the real posteromedial process is unpreserved with most of the posterior sternum.
Manual ungual I is said to be larger than ungual II, but this seems to be merely
due to the preserved keratinous sheath on ungual I, though larger manual ungual
I's are known in some enantiornithines (e.g. Jibeinia). The length of
manual digit I (76%- as measured from the base of the carpometacarpus to the
tip of phalanx I-1 compared to the length of the semilunate carpal plus metacarpal
II) is very similar to Jibeinia (71%) and especially Eoenantiornis
(76%). Metacarpal III being more slender than metacarpal II is found in most
theropods. Manual phalanx II-2 being shorter than II-1 is present in many derived
enantiornithines. The carpometacarpus being only fused proximally is true in
most enantiornithines. The unfused tibiotarsus is probably ontogenetic and is
known in the young holotypes of other enantiornithines (Protopteryx,
Rapaxavis, Dalingheornis, Jibeinia). Strong, curved pedal
unguals and a long pygostyle are present in most enantiornithines. Finally,
two pairs of elongate retrices are known in Shanweiniao.
Comments- While Zheng et al. (2007) refer Paraprotopteryx to the
Liaoning Formation of Fengning, they also state Protopteryx, Jibeinia
and Vescornis (= Hebeiornis) are from this locality. Jin et al.
(2008) reassigned it to the Qiaotou Member of the Huajiying Formation. Zheng
et al. state the skull "seems not to be the same individual as the postcranial
bones after careful examination", and the portion of the slab containing
the skull and cervical vertebrae does seem to contain an additional left coracoid.
Zheng et al. stated Paraprotopteryx was most similar to Protopteryx
due to several characters. Of these, the unfused tibiotarsus is probably ontogenetic
while the carpometacarpus is not unfused in Paraprotopteryx. Elongate
paired retrices are also known in Jibeinia, Longirostravis, Shanweiniao
and Dapingfangornis and seem standard for enantiornithines. The shared
character of "complete manual claws" probably refers to the presence
of two phalanges on digit III, which is seen in all basal enantiornithines including
Pengornis, Jibeinia, Longipteryx, Longirostravis,
Rapaxavis and Eocathayornis.
References- Zheng, Zhang and Hou, 2007. A new enantiornithine bird with
four long retrices from the Early Cretaceous of Northern Hebei, China. Acta
Geologica Sinica. 81(5), 703-708.
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx
and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science
Bulletin. 53(18), 2820-2827.
Parvavis Wang, Zhou and Xu,
2014
P. chuxiongensis Wang, Zhou and Xu, 2014
Turonian-Santonian, Late Cretaceous
Jiangdihe Formation, Yunnan, China
Holotype- (IVPP V18586) (subadult) occiput, several cervical vertebrae,
six caudal vertebrae, incomplete pygostyle, humeri (18.4 mm), radius (18.4 mm),
ulna (18.6 mm), femur (14.5 mm), tibiotarsi (one partial; 17.7 mm), metatarsals
I, phalanges I-1 (2.6 mm), pedal unguals I (3 mm), tarsometatarsi (9.5 mm),
phalanges II-1 (2.3 mm), phalanges II-2 (3.1 mm), pedal unguals II (4.5 mm),
phalanges III-1 (3.1 mm), phalanges III-2 (2.6 mm), pahlanges III-3 (2.5 mm),
pedal unguals III (4.2 mm), phalanges IV-1 (1.7 mm), phalanges IV-2 (1.7 mm),
phalanx IV-3 (1.9 mm), phalanges IV-4 (1.9 mm), pedal unguals IV (2.9 mm), feathers
Diagnosis- (after Wang et al., 2014) small, with humerus less than half
as long as that of Longipteryx; proximal profile of humerus concave;
anterior face immediately distal to head concave; deltopectoral crest narrower
than shaft width; ventral side of distal humerus extending more distally than
dorsal side; (combination of) metatarsals II and IV and proximal to entire trochlea
of metatarsal III; trochlea of metatarsal II broader than those of II and IV
(also in many other enantiornithines such as Eoenantiornis and Vescornis);
ungual of digit IV reduced (also in in Vescornis and Qiliania).
Comments- The holotype was discovered in 2010 and found by Wang et al.
(2014) to be the most basal examined non-longipterygid enantiornithine when
entered in O'Connor's analysis.
Reference- Wang, Zhou and Xu, 2014. The first enantiornithine bird from
the Upper Cretaceous of China, Journal of Vertebrate Paleontology. 34(1), 135-145.
Piscivorenantiornis Wang and Zhou, 2017
P. inusitatus Wang and Zhou, 2017
Early Albian, Early Cretaceous
Dapingfang, Jiufotang Formation, Liaoning, China
Holotype- (IVPP V22582)
premaxillae, frontal, braincase, quadrates, dentary, splenials,
surangulars, atlas, eight cervical vertebrae, nine dorsal vertebrae,
dorsal ribs, gastralia, synsacrum, six caudal vertebrae, scapula,
coracoids (24.4, 24.3 mm), furcula, sternum, humeri (40.5 mm), radii
(40.5, 40.6 mm), ulnae (44.2, 43.0 mm), scapholunares, pisiforms,
carpometacarpi (mc 4.1, cmc 19.1 mm), phalanx I-1, manual ungual (?)I,
pelves (ilium 27.9, pubis 36.2, ischium 22.4 mm), femora (35.0 mm),
tibiotarsi (one partial), fibulae, metatarsal I, tarsometatarsus (mtII
19.7, mtIII 21.8, mtIV 19.9 mm), six pedal phalanges, two pedal
unguals, gastric pellet (22.6 mm)
Early Albian, Early Cretaceous
Sihedang, Jiufotang Formation, Liaoning, China
Referred- (IVPP V23362)
incomplete skull, mandible, atlas, four anterior cervical vertebrae,
mid cervical vertebra, posterior cervical vertebra, four dorsal
vertebrae, dorsal ribs, uncinate processes, gastralia, synsacrum, four
caudal vertebrae, pygostyle, scapulae, coracoids, furcula, sternum,
humeri (one incomplete), incomplete radii, ulnae (one partial),
scapholunare, pisiform, carpometacarpus, phalanx I-1, phalanx II-1,
phalanx II-2, incomplete pelves, femora (one partial), tibiotarsi (one
incomplete), fibula, tarsometatarsus, six pedal phalanges, two pedal
unguals, pedal claw sheaths (Wang and Zhou, 2020)
Diagnosis- (after Wang and
Zhou, 2017) premaxillary symphysis notched anteriorly; anterior
articular facets of posterior cervical vertebrae dorsoventrally
concave and
mediolaterally convex; ventral margin of preacetabular process straight.
(after Wang and Zhou, 2020) exoccipital with pair of round fossae lateral to foramen magnum.
Comments- The holotype was
discovered before October 2015 and initially briefly described by Wang
et al. (2016) as an enantiornithine for which "a detailed morphological
study of the new specimen is in preparation and will be presented in a
separated paper." This was published the next year by Wang and
Zhou (2017), who officially named and described the taxon. Both
papers added it to O'Connor's avialan analysis and recovered it as
close to Pterygornis, Dunhuangia and bohaiornithids. Wang and Zhou (2020) described a referred specimen, and using more taxa recovered Piscivorenantiornis sister to Mirusavis plus Shangyang.
References- Wang, Zhou and
Sullivan, 2016. A fish-eating enantiornithine bird from the Early
Cretaceous of China provides evidence of modern avian digestive
features. Current Biology. 26, 1170-1176.
Wang and Zhou, 2017. A morphological study of the first known
piscivorous enantiornithine bird from the Early Cretaceous of China.
Journal of Vertebrate Paleontology. 37(2), e1278702.
Wang and Zhou, 2020. Anatomy of a new specimen of Piscivorenantiornis inusitatus
(Aves: Enantiornithes) from the Lower Cretaceous Jehol biota. Journal
of Vertebrate Paleontology. 40(3), e1783278.
Pterygornis Wang, Hu
and Li, 2015
= "Dispersusia" Wang, Hu and Li, 2015
P. dapingfangensis Wang, Hu and Li, 2015
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V20729) (adult) partial skull, sclerotic ossicles, incomplete
mandible, atlas, axis, six postaxial cervical vertebrae, seven dorsal vertebrae,
dorsal ribs, synsacrum, six caudal vertebrae, pygostyle (12.3 mm), scapulae,
coracoids (15.9 mm), incomplete sternum, sternal ribs, humeri (25.3 mm), radii
(26.4 mm), ulnae (28.3 mm), scapholunares, pisiforms, carpometacarpi (13.3 mm, mcI
2.4 mm), phalanx I-1 (4.4 mm), phalanx II-1 (7.1 mm), femora (23.8 mm), tibiotarsi
(28.6 mm), fibulae (12.2 mm), metatarsals I, tarsometatarsi (mtII 15.1, mtIII
17, mtIV 15.6 mm), fifteen pedal phalanges, six pedal unguals
Diagnosis- (after Wang et al., 2015) proximal half of coracoid shaft
curved medially (also in Cathayornis and Eocathayornis); sternum
with external anteromedian spine (possibly external spine also in Eocathayornis
and Houornis); sternum with anterolateral processes (also in Rapaxavis
and Concornis); metatarsal II strongly ginglymoid articulation; wide
articular furrow on plantar surface of metatarsal II.
Other diagnoses- Wang et al. also view the surangular as diagnostic,
proposing it has an anteroventrally sloping anterior margin. Yet this would
be unlike almost all other theropods, and not match the slope of the dentary
(Wang et al. propose they form an autapomorphic overlapping articulation). Note
the supposed angular is continuous posteriorly with the surangular, flaring
at its posterior end. These facts make it more likely the surangular is a left
element in medial view and that the 'angular' is the ridge dorsal to the Meckelian
fossa, comparable to Archaeopteryx. The authors also propose the distally
fused first and second metacarpals to be unique among Early Cretaceous enantiornithines,
but correctly note the condition is present in several Late Cretaceous members
of that group.
Comments- The name "Dispersusia" is used and bolded in Wang
et al.'s cladogram, no doubt an earlier name for Pterygornis in reference
to the dispersed elements of the holotype. Wang et al. entered Pterygornis
into a version of O'Connor's bird matrix and found it to be more derived than
longipterygids, in a position just closer to avisaurids than to bohaiornithids.
Reference- Wang, Hu and Li, 2015. A new small enantiornithine bird from
the Jehol Biota, with implications for early evolution of avian skull morphology.
Journal of Systematic Palaeontology. DOI:10.1080/14772019.2015.1073801
Euenantiornithes Chiappe, 2002
Definition- (Sinornis santensis <- Iberomesornis romerali)
(modified from Chiappe, 2002)
Sinornithiformes Hou, 1997
"Sinornithidae" Hou, 1997
Comments- As Hou (1997) did not define or diagnose Sinornithidae, it
is a nomen nudum (ICZN Article 13.1.1).
References- Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park,
Lugu Hsiang, Taiwan. 221 pp.
Sinornis Sereno and Rao, 1992
S. santensis Sereno and Rao, 1992
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (BPV 538) incomplete skull (~26.5 mm), partial mandibles, eleven
dorsal vertebrae (2.4, 2.3 mm; dorsal column ~30.5 mm), dorsal ribs, sacrum
(12.9 mm; first sacral 2.5 mm, eighth sacral 1.5 mm), first caudal vertebra
(1.6 mm), second caudal vertebra (1.5 mm), third caudal vertebra (1.5 mm), fourth
caudal vertebra (1.3 mm), fifth caudal vertebra (1 mm), sixth caudal vertebra
(.6 mm), five chevrons, pygostyle (11.5 mm), scapula (~18 mm), partial coracoid,
furcula, partial sternum, incomplete humerus (24 mm), partial radii (~22.2 mm),
partial ulnae (~19.2 mm), scapholunare, pisiform, carpometacarpus (10.3 mm; metacarpal
I ~1.9 mm, metacarpal III ~10.8 mm), phalanx I-1 (4 mm), manual ungual I (1.6
mm), phalanx II-1 (5.4 mm), phalanx II-2 (3.8 mm), manual ungual II (2.1 mm),
phalanx III-1 (3.9 mm), incomplete ilium (~13 mm), pubes, ischia, femora (~21
mm), tibiotarsi (25.7, 26.4 mm), fibulae, metatarsal I (3.2 mm), phalanx I-1
(3.7 mm), pedal ungual I (5.6 mm), tarsometatarsi (metatarsal II 14.1 mm, metatarsal
III 14.6 mm, metatarsal IV 14.1 mm), phalanx II-1 (3.2 mm), phalanx II-2 (4.1
mm), pedal ungual II (5.8 mm), phalanx III-1 (4.3 mm), phalanx III-2 (3.6 mm),
phalanx III-3 (3.9 mm), pedal ungual III (6.7 mm), phalanx IV-1 (2.1 mm), phalanx
IV-2 (2.1 mm), phalanx IV-3 (2.1 mm), phalanx IV-4 (3 mm), pedal ungual IV (5.3
mm)
References- Sereno and Rao, 1992. Early evolution of avian flight and
perching: New evidence from the Lower Cretaceous of China. Science. 255, 845-848.
Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park, Lugu Hsiang, Taiwan.
221 pp.
Sereno, Rao and Li, 2002. Sinornis santensis (Aves: Enantiornithes) from
the Early Cretaceous of Northeastern China. pp 184-208. in Chiappe and Witmer,
(eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University of California
Press, Berkeley, Los Angeles, London.
Zhou and Hou, 2002. The Discovery and Study of Mesozoic Birds in China. pp 160-183.
in Chiappe and Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs.
University of California Press, Berkeley, Los Angeles, London.
O'Connor and Dyke, 2010. A reassessment of Sinornis santensis and Cathayornis
yandica (Aves: Enantiornithes). Records of the Australian Museum. 62, 7-20.
Xiangornis Hu, Xu, Hou and Sullivan,
2012
X. shenmi Hu, Xu, Hou and Sullivan, 2012
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (PMOL-AB00245) coracoid (35 mm), incomplete furcula, sternal
fragment, proximal humerus, distal radius, distal ulna, incomplete carpometacarpus
(38.5 mm), phalanx I-1 (15.2 mm)
Diagnosis- (after Hu et al., 2012) large size; coracoid with medially
curved acrocoracoid process; proximally convex humeral head; carpometacarpus
longer than coracoid and completely fused both proximally and distally; short
metacarpal I (about one-sixth of the length of metacarpal II) completely fused
to metacarpal II; large, flange-like extensor process; intermetacarpal space
positioned significantly distal to metacarpal I.
Comments- The holotype was discovered in 2005. Hu et al. included it
in a version of Clarke's matrix and found it to be an enantiornithine.
Reference- Hu, Xu, Hou and Sullivan, 2012. A new enantiornithine bird
from the Lower Cretaceous of western Liaoning, China, and its implications for
early avian evolution, Journal of Vertebrate Paleontology. 32(3), 639-645.
Yuornis Xu, Buffetaut, O'Connor, Zhang, Jia, Zhang, Chang and Tong, 2021
Y. junchangi Xu, Buffetaut, O'Connor, Zhang, Jia, Zhang, Chang and Tong, 2021
Late Cretaceous
Qiupa Formation, Henan, China
Holotype-
(L-08-7-3) incomplete skull (62 mm), sclerotic plates, mandibles (50
mm), two partial ribs, fragmentary synsacrum, proximal scapulae,
proximal coracoid, humeri (73 mm), radii (one fragmentary; 72 mm),
ulnae (78 mm), distal metacarpals II, partial phalanges II-1, partial
phalanges II-2, manual ungual II, distal metacarpals III, phalanx
III-1, ilial fragment, incomplete femur, incomplete tibiotarsus, two
phalanges IV-?
Diagnosis- (after Xu et al.,
2021) antorbital fenestra and supratemporal fenestra completely
confluent with orbit; quadratojugal with hook-like process that curves
around the lateral condyle
of the quadrate; acromion process with narrow pedicel with sulcus the
lateral surface; deltopectoral crest more than one-third the length of
the humerus and separated from the dorsal tubercle. Differs from Gobipteryx
in having a proportionately longer and narrower rostrum that is not
upturned rostrally; well developed nasal process on maxilla; external
nares proportionately narrower.
Comments- Lu et al. (2011) briefly describe this specimen
in an abstract and refer it to the Gobipterygidae. Xu et al. (2021)
officially described it and recovered Yuornis sister to Gobipteryx using O'Connor's bird analysis.
References- Lu, Xu, Zhang, Jia and Chang, 2011. A new gobipterygid bird
from the Late Cretaceous Central China and its biogeographic implications. Journal
of Vertebrate Paleontology. Program and Abstracts 2011, 147.
Xu, Buffetaut, O'Connor, Zhang, Jia, Zhang, Chang and Tong, 2021. A new, remarkably preserved, enantiornithine bird from the
Upper Cretaceous Qiupa Formation of Henan (central China) and
convergent evolution between enantiornithines and modern birds.
Geological Magazine. 158(11), 2087-2094.
Yungavolucris Chiappe,
1993
Y. brevipedalis Chiappe, 1993
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4053) (~340 mm) tarsometatarsus (41.9 mm)
Paratypes- (PVL-4040) incomplete tarsometatarsus (41.6 mm)
(PVL-4052) incomplete tarsometatarsus (51.9 mm) (Chiappe, 1991)
(PVL-4268) distal metatarsal II, distal metatarsal III
(PVL-4692) distal tarsometatarsus (42.8 mm)
Comments- Walker et al. (2007) mistakenly assigned the holotype to Avisaurus.
Based on size, it may correspond with Elbretornis.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Chiappe, 1991. Cretaceous birds of Latin America. Cretaceous Research. 12(1),
55-63.
Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho
Formation of Northwestern Argentina. American Museum Novitates. 3083, 39 pp.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
undescribed enantiornithine (Martin and Stewart, 1982)
Campanian, Late Cretaceous
Pembina Member of the Vermillion River Formation, Manitoba, Canada
Material- (CFDC B.77.03.07) dorsal vertebra (6 mm)
Comments- Referred to Ichthyornis sp. by Martin and Stewart (1982),
and later to Enantiornithes by Clarke (2004) because of its centrally placed
parapophyses.
References- Martin and Stewart, 1982. An ichthyornithiform bird from
the Campanian of Canada. Canadian Journal of Earth Sciences. 19, 324-327.
Nicholls, 1989. Marine vertebrates of the Pembina Member of the Pierre Shale
(Campanian, Upper Cretaceous) of Manitoba and their significance to the biogeography
of the Western Interior Seaway. University of Calgary.
Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis
and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural
History. 286: 1-179.
unnamed Enantiornithes (Shufeldt, 1915)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Material- (USNM 2909) distal metatarsal II, two distal pedal phalanges (Gilmore, 1920)
(YPM 865) distal metatarsal III, two fragments (Shufeldt, 1915)
Comments- USNM 2909 was originally referred to Ornithomimus minutus
by Gilmore (1920) but later to Euenantiornithes by Chiappe and Walker
(2002). Similarly, Shufeldt (1915) listed YPM 865 as
indeterminate fragmentary bird material, but Chiappe and Walker later
identified it as euenantiornithine.
References- Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale
University. Transactions of the Connecticut Academy of Arts and
Sciences. 19, 1-110.
Gilmore, 1920. Osteology of the carnivorous Dinosauria in
the United States National Museum, with special reference to the genera Antrodemus
(Allosaurus) and Ceratosaurus. United States National Museum,
Bulletin. 110, 1-154.
Chiappe and Walker, 2002. Skeletal morphology and systematics
of the Cretaceous Euenantiornithes (Ornithothoraces: Enantiornithes). In Chiappe
and Witmer (eds.). Mesozoic
Birds, Above the Heads of Dinosaurs. University of California Press. 240-267.
unnamed enantiornithine (Walker, Buffetaut and Dyke, 2007)
Campanian, Late Cretaceous
Lance's Quarry, New Mexico, US
Material- (KU-NM-37) proximal humerus
Comments- Walker et al. (2007) refer this to Martinavis sp., but
the supposed apomorphies of that genus are not valid (see Martinavis
Other diagnoses) and there are no characters which it uniquely shares with M.
cruzyensis and/or vincei. The authors confusingly stated it is "the
most distinctive of [the] referred specimens" and that it "is indistinguishable
from other bones referred here to Martinavis." The broad capital
groove is more similar to M. cruzyensis, while the broad pneumotricipital
groove is more similar to M? vincei. It seems best to keep this specimen
out of Martinavis.
Reference- Walker, Buffetaut and Dyke, 2007. Large euenantiornithine
birds from the Cretaceous of southern France, North America and Argentina. Geological
Magazine. 144(6), 977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
unnamed enantiornithine (Sanz, Chiappe, Perez-Moreno, Moratalla, Hernandez-Carrasquilla,
Buscalioni, Ortega, Poyato-Ariza, Rasskin-Gutman and Martinez-Delclos, 1997)
Late Berriasian-Early Barremian, Early Cretaceous
La Pedrera de Rubies Lithographic Limestones, Spain
Material- (LP-4450-IEI) (juvenile) skull, mandible, hyoids, nine cervical
vertebrae, partial dorsal ribs, scapula, coracoid, furcula, humerus, radius,
ulna, carpometacarpus, phalanx I-1, manual ungual I, phalanx II-1, phalanx II-2,
manual ungual II, feather impressions
References- Morell, 1997. Fossilized hatchling heats up the bird-dinosaur debate. Science. 276, 1501.
Sanz, Chiappe, Perez-Moreno, Moratalla, Hernandez-Carrasquilla,
Buscalioni, Ortega, Poyato-Ariza, Rasskin-Gutman and Martinez-Delclos, 1997.
A nestling bird from the Lower Cretaceous of Spain: Implications for avian skull
and neck evolution. Science. 276, 1543-1546.
Marugan-Lobon, Cambra-Moo, Martinez-Delclos, Sanz and Buscalioni, 2002. Juvenile
enantiornithine skeleton from Montsec (Catalonia, Spain) Lower Cretaceous revisited:
Taphonomy and morphometrics to access ontogenetic stage. Journal of Vertebrate
Paleontology. 22(3), 84A.
undescribed enantiornithine (Sanz, Chiappe, Fernadez-Jalvo, Ortega,
Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001)
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Material- (LH 11386 bird 1) (juvenile) four posterior cervical vertebrae,
eleven dorsal vertebrae, dorsal neural spine, six dorsal ribs, sacrum, twelve
caudal vertebrae(?), scapulae, coracoids, sternum, sternal ribs, humerus, radius,
ulna, pisiform, phalanx I-1, manual ungual I, distal metacarpal II, proximal phalanx
II-1, partial ilium, proximal pubis, ischium, partial femur, astragalus, metatarsal
I, phalanx I-1, pedal ungual I, metatarsal II, phalanx II-1, phalanges II-2,
pedal unguals II, metatarsal III, phalanx III-1, phalanges III-2, phalanges
III-3, pedal ungual III, metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx
IV-3, phalanx IV-4, pedal ungual IV, fragments, remiges
Comments- This specimen is the most complete of four juvenile birds found
associated in a theropod or pterosaur pellet. It was only identified as a bird
by Sanz et al. (2001), and colored dark gray in their illustration. The strut-like
coracoid and tapered distal scapula are like avialans (though
confuciusornithids reverse the latter). The fused sterna are similar to euavialans,
though its small size and lack of lateral processes are no doubt due to its
young age, as seen in juvenile enantiornithines and confuciusornithids. Several
characters are unlike most euornithines, but similar to enantiornithines
and more basal birds. The absent procoracoid process is only found in Patagopteryx
and Apsaravis. The scapula being shorter than the humerus is only found
in Archaeorhynchus, Yanornis and Gansus. The medial tibiotarsal
condyle being wider than the lateral one is only seen in Patagopteryx.
Finally, the proximal end of metatarsal III is in the same plane as metatarsals
II and IV, which is only seen in Patagopteryx, Archaeorhynchus
and Hongshanornis among euornithines. Other characters are shared
only with enantiornithines with a few exceptions. The deep dorsal coracoid fossa
and narrow tibiotarsal intercondylar groove (~25% of tibiotarsal width) are
only present in enantiornithines and Apsaravis. The narrow sternal xiphoid
process is only present in enantiornithines and Hongshanornis. Metatarsal
IV being so narrow compared to II and III is uniquely enantionithine. Within
Enantiornithes, the specimen may be more derived than Protopteryx, Longipteryx
and Eoenantiornis based on its short manual digit I. The sternal xiphoid
process is distally expanded as in Longirostravis, Shanweiniao,
Eocathayornis, Eoalulavis and Liaoningornis. Yet metatarsal
II has a trochlea smaller than III, which among enantiornithines is only known
in longipterygids, Vorona and Liaoningornis. It may be most closely
related to Vorona, Liaoningornis, or Shanweiniao and Longirostravis.
Reference- Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza
and Perez-Moreno, 2001. An Early Cretaceous pellet. Nature. 409, 998-999.
unnamed enantiornithine (Buffetaut, Mechin and Mechin-Salessy, 2000)
Early Maastrichtian, Late Cretaceous
Bastide-Neuve, Provence, France
Material- (Mechin coll. no. 606) tibiotarsus (132 mm)
Comments- Buffetaut et al. (2000) referred this specimen to Enantiornithes
incertae sedis. The reduced fibula indicates this is an avialan,
while the tubercle on the ascending process is a pygostylian character. Although
uncommon, lack of fusion between the astragalocalcaneum and tibia is known in
some pygostylians (e.g. Longipteryx, Hebeiornis, Gobipteryx,
Vorona) and may be ontogenetic. The lack of medially tapering distal
condyles and narrow intercondylar groove are seen in most enantiornithines,
but also the basal euornithines Apsaravis and Longicrusavis.
The large medial condyle (~200% the width of the lateral one) is characteristic
of a subset of enantiornithines, including Nanantius, Gobipteryx
and Soroavisaurus.
Reference- Buffetaut, Mechin and Mechin-Salessy, 2000. An archaic bird
(Enantiornithes) from the Upper Cretaceous of Provence (Southern France). Comptes
Rendus de l'Academie des Sciences. 331, 557-561.
undescribed enantiornithine (Dyke, Vremir, Kaiser and Naish, 2011)
Maastrichtian, Late Cretaceous
Sebes Formation, Romania
Material- (EME V.314) (adult) scapula, coracoid, partial sternum, humerus,
ulna (75 mm), tibiotarsus (75 mm), (nestling) quadrate, cervical vertebra, dorsal
vertebrae, proximal scapula, proximal tibia, pedal phalanges, ~50 bone fragments,
seven incomplete eggs, thousands of eggshell fragments
Comments- This was hypothesized to be the remains of a nesting colony
by Dyke et al. (2012), who suggested the taxon is very closely related to Enantiornis.
References- Dyke, Vremir, Kaiser and Naish, 2011. A drowned Mesozoic
bird breeding colony. Journal of Vertebrate Paleontology. Program and Abstracts
2011, 103.
Dyke, Vremir, Kaiser and Naish, 2012. A drowned Mesozoic bird breeding colony
from the Late Cretaceous of Transylvania. Naturwissenschaften. 99, 435-442.
unnamed enantiornithine (Nessov and Borkin, 1983)
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material- (ZIN PO 3494) proximal tarsometatarsus
Comments- Discovered in 1979, this was identified as an enantiornithid
by Nessov and Borkin (1983), then as an enantiornithiform by Nesov (1984a,b, 1992).
Kurochkin (1996) referred it to Alexornithidae within Enantiornithes. This was
based on the strongly reduced metatarsal IV, which however seems to characterize
most enantiornithines except for Aberratiodontus, Iberomesornis,
Liaoningornis and Vorona. The extremely enlarged medial tibiotarsal
condyle (based on the tarsometatarsal cotyla it was ~225% the width of the lateral
condyle) is characteristic of a derived set of enantiornithines including Gobipteryx,
Nanantius and Soroavisaurus though.
References- Nessov and Borkin, 1983. New records of bird bones from the
Cretaceous of Mongolia and Soviet Middle Asia. USSR Academy of Sciences, Proceedings
of the Zoological Institute. 116, 108-110 (in Russian).
Nesov, 1984a. Pterozavry i ptitsy pozdnego mela Sredney Azii. Paleontologicheskii Zhurnal. 1, 47-57.
Nesov, 1984b. Upper Cretaceous pterosaurs and birds from central Asia. Paleontological Journal. 1, 38-49.
Nessov, 1992a. Mesozoic and Paleogene birds of the USSR and their
paleoenvironments. In Campbell (ed.). Papers in Avian Paleontology
Honoring Pierce Brodkorb. Natural History Museum of Los Angeles County
Science Series. 36, 465-478.
Kurochkin, 1996. A new enantiornithid of the Mongolian Late Cretaceous, and
a general appraisal of the Infraclass Enantiornithes (Aves). Russian Academy
of Sciences, Palaeontological Institute, special issue. 50 pp.
unnamed enantiornithine (Chiappe and Calvo, 1994)
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Material- (MACN-S-01) femur (93.5 mm) (Chiappe and Calvo, 1994)
Comments- MACN-S-01 was first noted by Chiappe and Calvo (1994), while
Chinsamy et al. (1995) examined its histology. It is from an enantiornithine
based on its hypertrophied posterior trochanter and resembles Vorona,
Neuquenornis and Concornis in having a posteriorly projected lateral
border on the distal femur.
References- Chiappe and Calvo, 1994. Neuquenornis volans, a new
Enantiornithes (Aves) from the Upper Cretaceous of Patagonia (Argentina). Journal
of Vertebrate Paleontology. 14, 230-246.
Chinsamy, Chiappe and Dodson, 1995. Mesozoic avian bone microstructure: Physiological
implications. Paleobiology. 21(4), 561-574.
unnamed Enantiornithes (Naish, Martill and Merrick, 2007)
Late Aptian, Early Cretaceous
Nova Olinda Member of the Crato Formation, Brazil
Material- (MURJ private coll.) incomplete skull, twenty-two presacral vertebrae,
cervical ribs, two dorsal ribs, fragmentary sacrum, three caudal vertebrae,
caudal vertebral fragments, chevron, partial ilium, ?ischium, femur (~40 mm),
tibiotarsus (~39 mm), phalanx I-1, pedal ungual I, tarsometatarsus (~31 mm),
pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III,
phalanx IV-4, pedal ungual IV, pedal claw sheaths, body feathers
Comments- Naish et al. (2007) refer a specimen in a private collection
to Euenantiornithes based on the centrally placed dorsal parapophyses. The dorsal
neural spines are expanded axially at their tips, which Naish et al. notes is
similar to Cathayornis (their Sinornis), though it is also present
in several other enantiornithines (e.g. Eoalulavis, Fortunguavis,
Longusunguis, Noguerornis, Parabohaiornis, Rapaxavis,
Shenqiornis, Zhouornis). The authors proposed the presence of
two central fossae on the first caudal vertebra could be an autapomorphy.
Reference- Naish, Martill and Merrick, 2007. Birds of the Crato Formation.
In Martill, Bechly and Loveridge (eds.). The Crato fossil beds of Brazil: Window
into an ancient world. Cambridge University Press. 525-533.
Avisauroidea Paul and Brett-Surman, 1985 vide Martyniuk, 2012
Definition- (Avisaurus archibaldi <- Longipteryx chaoyangensis,
Sinornis santensis, Gobipteryx minuta) (Martyniuk, 2012)
Avisauridae Paul and Brett-Surman, 1985
Definition- (Avisaurus archibaldi + Neuquenornis volans) (Chiappe,
1993)
Other definitions- (Avisaurus archibaldi <- Longipteryx chaoyangensis,
Sinornis santensis, Gobipteryx minuta) (Cau and Arduini, 2008)
References- Brett-Surman and Paul, 1985. A new family of bird-like dinosaurs
linking Laurasia and Gondwanaland. Journal of Vertebrate Paleontology. 5(2),
133-138.
Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho
Formation of northwestern Argentina. American Museum Novitates. 3083, 39 pp.
Cau and Arduini, 2008. Enantiophoenix electrophyla gen. et sp. nov. (Aves,
Enantiornithes) from the Upper Cretaceous (Cenomanian) of Lebanon and its phylogenetic
relationships. Atti Soc. it. Sci. nat. Museo civ. Stor. nat. Milano. 149(II),
293-324.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs.
Vernon, New Jersey. Pan Aves. 189 pp.
Atterholt, Hutchison and O'Connor, 2018. The most complete
enantiornithine from North America and a phylogenetic analysis of the
Avisauridae. PeerJ. 6:e5910.
Avisaurus Brett-Surman and Paul, 1985
A. archibaldi Brett-Surman and
Paul, 1985
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, US
Holotype- (UCMP 117600) (~550 mm) tarsometatarsus (mtII 68.7, mtIII 73.9, mtIV 67.8 mm)
Paratype- (PU 17324) tarsometatarsus
Referred- ?(UCMP 171634) (juvenile) metatarsal III (UCMP online; Stidham and Hutchison, 1999?)
?(UCMP 174717) phalanx (UCMP online)
?(YPM 57235) proximal coracoid (Longrich, Tokaryk and Field, 2011)
(large) distal tibiotarsus (Stidham and Hutchison, 2001)
Comments-
The holotype was discovered on July 24 1975. Glut (1982) notes
Brett-Surman proposed this and an Argentinian form (presumably what
would be later named Soroavisaurus)
as a new theropod family
at the 1978 Society of Vertebrate Paleontology meeting.
Brett-Surman and Paul (1985) also designated PVL-4690 and PVL-4048 as
paratypes, but they were later made the holotype and paratype
respectively of Soroavisaurus australis (Chiappe, 1993).
Stidham and Hutchison (2001) mention "tarsometatarsal fragments
representing one or two undescribed taxa" from the Hell Creek Formation
of Montana. They (1999) state "A juvenile Avisaurus
specimen of an undescribed species from the Maastrichtian Hell Creek
Formation of Montana reveals the presence of distal tarsals in
enantiomithines." At his 2002
SVP presentation, Stidham used a juvenile avisaurid metatarsal to show
that the distal tarsals fused to the metatarsals before the metatarsals
fuse to each other in enantiornithines (Mortimer, DML 2002). This
may be UCMP 171634, a
metatarsal III on the UCMP online database.
References- Glut, 1982. The New Dinosaur Dictionary. Citadel Press. 288 pp.
Brett-Surman and Paul, 1985. A new family of bird-like dinosaurs
linking Laurasia and Gondwanaland. Journal of Vertebrate Paleontology. 5(2),
133-138.
Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho
Formation of northwestern Argentina. American Museum Novitates. 3083, 39 pp.
Stidham and Hutchison, 1999. The North American avisaurids (Aves: Enantiornithes):
New data on morphology and phylogeny. VII International Symposium on Mesozoic
Terrestrial Ecosystems, abstracts. 61.
Stidham and Hutchison, 2001. The North American avisaurids (Aves: Enantiornithes):
New data on biostratigraphy and biogeography. In Bonaparte (ed.). VII International Symposium on Mesozoic Terrestrial
Ecosystems. Asociaci�n Paleontol�gica
Argentina Publicaci�n Especial. 7, 175-177.
Mortimer, DML 2002. https://web.archive.org/web/20161206234325/http://dml.cmnh.org/2002Oct/msg00295.html
Stidham, 2002. Evolutionary and developmental origin of the extant bird tarsometatarsus
from its theropod dinosaur ancestry. Journal of Vertebrate Paleontology. 22(3),
111A.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the
Cretaceous–Paleogene (K–Pg) boundary. Proceedings of the National
Academy of Sciences of the United States of America. 108(37),
15253-15257.
Gettyia Atterholt, Hutchison and O'Connor, 2018
G. gloriae (Varricchio and Chiappe, 1995) Atterholt, Hutchison and O'Connor, 2018
= Avisaurus gloriae Varricchio and Chiappe,
1995
Middle-Late Campanian, Late Cretaceous
Two Medicine Formation, Montana, US
Holotype- (MOR 553E/6.19.91.64) (~230 mm) tarsometatarsus (mtII 28.4, mtIII 30.9, mtIV 28.5 mm)
Comments- This specimen was discovered in summer 1991 and first referred to as the Two Medicine form in
Chiappe (1993).
Diagnosis- (after Varricchio
and Chiappe, 1995) mid-length cross-section of tarsometatarsus
relatively straight; attachment for the m. tibialis cranialis located
beyond the midpoint of
the tarsometatarsus; small, medially-curving ridge on the dorsal distal
portion of metatarsal II; distal vascular foramen completely closed by
metatarsal IV.
(after Atterholt et al., 2018) dorsal surface of the tarsometatarsus strongly inclined.
References- Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from
the Cretaceous Lecho Formation of northwestern Argentina. American Museum Novitates.
3083, 39 pp.
Varricchio and Chiappe, 1995. A new enantiornithine bird from the Upper Cretaceous
Two Medicine Formation of Montana. Journal of Vertebrate Paleontology. 15(1),
201-204.
Atterholt, Hutchison and O'Connor, 2018. The most complete
enantiornithine from North America and a phylogenetic analysis of the
Avisauridae. PeerJ. 6:e5910.
Mirarce
Atterholt, Hutchison and O'Connor, 2018
M. eatoni
Atterholt, Hutchison and O'Connor, 2018
Late Campanian, Late Cretaceous
Kaiparowitz Formation, Utah, US
Holotype- (UCMP 139500)
(adult) axis (18.1 mm), third cervical vertebra, posterior cervical
vertebra, two incomplete dorsal vertebrae, pygostyle (37.9 mm),
incomplete scapula, partial coracoid, furcula, posterior sternum,
humerus (95.9 mm), partial radius, incomplete ulna, carpometacarpal
fragment, distal metacarpal II, phalanx II-1, partial pelvis, femora
(one fragmentary; 89 mm), fragmentary tibiotarsus, phalanx I-1, pedal
ungual I, tarsometatarsi (one proximal; mtII 44.1, mtIII 48.2, mtIV
45.9 mm), phalanges II-1, phalanges II-2, pedal ungual II, phalanges
III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1,
phalanx IV-3, phalanx IV-4, pedal ungual IV, seven pedal phalanges
(incl. unguals)
Diagnosis- (after Atterholt et
al., 2018) posterior end of sternum weakly flexed posterodorsally,
terminating in a small knob; ulnae with remix papillae present; small,
deep, circular pit located just
anterolateral to femoral posterior trochanter; small, triangular muscle
scar on medial margin of femoral shaft, just distal to the head,
followed distally by much larger proximodistally elongate oval;
distinct, rugose ridge-like muscle attachment located on anteromedial
margin of femur one fourth from the distal end; tubercle for m.
tibialis cranialis located at mid-point of shaft of metatarsal II on
the dorsal surface.
Comments- This was discovered on October 12 1992 and initially identified as Avisaurus
sp. nov. (Hutchison, 1993), though note that abstract incorrectly
claimed evidence of "sharply clawed digits on the wing." Stidham
and Hutchison (1999) noted it in an abstract as an "undescribed
crowsized partial skeleton of Avisaurus from the Campanian Kaiparowits Formation." Hutchinson
(2001) illustrates the proximal femur as Avisaurus and notes a few characters.
References- Hutchison, 1993. Avisaurus: A "dinosaur"
grows wings. Journal of Veterbrate Paleontology. 13(3), 43A.
Stidham and Hutchison, 1999. The North American avisaurids (Aves: Enantiornithes):
New data on morphology and phylogeny. VII International Symposium on Mesozoic
Terrestrial Ecosystems, abstracts. 61.
Hutchinson, 2001. The evolution of femoral osteology and soft tissues on the
line to extant birds (Neornithes). Zoological Journal of the Linnean Society. 131, 169-197.
Chiappe and Walker, 2002. Skeletal morphology and systematics of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). In Chiappe and
Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University
of California Press. 240-267.
Atterholt, Hutchison and O'Connor, 2018. The most complete
enantiornithine from North America and a phylogenetic analysis of the
Avisauridae. PeerJ. 6:e5910.
Soroavisaurus Chiappe, 1993
S. australis Chiappe, 1993
Maastrichtian, Late Cretaceous
Lecho Formation, Salta, Argentina
Holotype- (PVL-4690; paratype of Avisaurus archibaldi) (~345 mm)
tarsometatarsus (46.9 mm; metatarsal II 44.2, metatarsal IV 43.3 mm)
Paratype- (PVL-4048; paratype of Avisaurus archibaldi) metatarsal
I (12.2 mm), phalanx I-1 (16.2 mm), ungual I (17.3 mm), tarsometatarsus (51.5
mm; metatarsal II 48.9, metatarsal IV 48.4 mm), four pedal phalanges
Referred- ?(PVL-4033) tibiotarsus (85.6 mm) (Walker, 1981)
Comments-
Collected between 1974 and 1976, PVL-4048 was originally illustrated by
Walker (1981). Glut (1982) notes Brett-Surman proposed what is
presumably this and Avisaurus as a new theropod family
at the 1978 Society of Vertebrate Paleontology meeting. Brett-Surman
and Paul (1985) made it and PVL-4690 paratypes of Avisaurus archibaldi,
though they referred to PVL-4690 as Avisaurus sp. and 4048 as Avisauridae
in an illustration. They were also referred to Avisaurus sp. by Chiappe
(1992) and Chiappe and Calvo (1994). Chiappe (1993) named them both Soroavisaurus
australis.
PVL-4033 was also originally illustrated by Walker (and referred to Martinavis
by him in his unpublished manuscript), but not referred to Soroavisaurus
until Chiappe and Walker (2002). The latter authors also referred PVL-4030 to
Soroavisaurus and illustrated both tibiotarsi. Walker and Dyke (2009)
reassigned PVL-4030 to Martinavis sp. and assigned PVL-4033 to Martinavis
in their measurement table. Walker et al. (2007) stated PVL-4033 is consistant
in size with both Enantiornis and Martinavis. The smaller size
of Soroavisaurus does suggest it may correspond with humeri of Martinavis?
vincei or M? saltariensis, making the assignment of elements like
tibiotarsi to either taxon more semantic than scientific.
References- Walker, 1981. New subclass of birds from the Cretaceous of
South America. Nature. 292, 51-53.
Glut, 1982. The New Dinosaur Dictionary. Citadel Press. 288 pp.
Brett-Surman and Paul, 1985. A new family of bird-like dinosaurs linking Laurasia
and Gondwanaland. Journal of Vertebrate Paleontology. 5(2), 133-138.
Chiappe, 1992. Enantiornithine (Aves) tarsometatarsi and the avian affinites
of the Cretaceous Avisauridae. Journal of Vertebrate Paleontology. 12(3), 344-350.
Chiappe, 1993. Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho
Formation of northwestern Argentina. American Museum Novitates. 3083, 39 pp.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Enantiornithes (Aves)
from the Upper Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology.
14, 230–246.
Chiappe and Walker, 2002. Skeletal morphology and systematic of the Cretaceous
Euenantiornithes (Ornithothoraces: Enantiornithes). pp 240-267. in Chiappe and
Witmer, (eds.). Mesozoic Birds – Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Walker, Buffetaut and Dyke, 2007. Large euenantiornithine birds from the Cretaceous
of southern France, North America and Argentina. Geological Magazine. 144(6),
977-986.
Walker and Dyke, 2009. Euenantiornithine birds from the Late Cretaceous of El
Brete (Argentina). Irish Journal of Earth Sciences. 27, 15-62.
Neuquenornis Chiappe and Calvo,
1994
N. volans Chiappe and Calvo, 1994
Santonian, Late Cretaceous
Bajo de le Carpa Formation of the Rio Colorado Subgroup, Neuquen, Argentina
Holotype- (MUCPv-142) (~290 mm) posterior skull, five partial dorsal
vertebrae, incomplete scapula, coracoids (33.4 mm), furcula, incomplete sternum,
sternal ribs, incomplete humeri, incomplete radii (70.5 mm), incomplete ulnae
(72.1 mm), pisiform, carpometacarpus, proximal phalanx II-1, pelvic(?) fragment,
incomplete femur, partial tibiotarsi (~87.7 mm), metatarsal I (8.3 mm), phalanx
I-1 (10.7 mm), pedal ungual I (14.6 mm), incomplete tarsometatarsi (~46.8 mm),
phalanx II-1 (6.6 mm), phalanx II-2 (12.3 mm), partial pedal ungual II (11.7
mm), phalanx III-1 (10.7 mm), phalanx III-2
References- Chiappe and Calvo, 1989. El primer Enantiornithes (Aves)
del Cretacico de Patagonia. Resumes VI Jornadas Argentinas de Paleontologia
de Vertebrados. San Juan. pp. 19-21.
Chiappe, 1991a. Cretaceous birds of Latin America. Cretaceous Research. 12(1),
55-63.
Chiappe, 1991b. Cretaceous avian remains from Patagonia shed new light on the early radiation of birds. Alcheringa. 15, 333-338.
Chiappe, 1992. Enantiornithine (Aves) tarsometatarsi and the avian affinites
of the Cretaceous Avisauridae. Journal of Vertebrate Paleontology. 12(3), 344-350.
Chiappe and Calvo, 1994. Neuquenornis volans, a new Late Cretaceous bird
(Enantiornithes: Avisauridae) from Patagonia, Argentina. Journal of Vertebrate
Paleontology. 14(2), 230-246.
Intiornis Novas, Agnolin
and Scanferla, 2010
I. inexpectatus Novas, Agnolin and Scanferla, 2010
Campanian, Late Cretaceous
Las Curtiembres Formation, Salta, Argentina
Holotype- (MAS-P/2 1) distal tibiotarsus, metatarsal I, phalanx I-1, pedal
ungual I, tarsometatarsus (21 mm), phalanx II-1, phalanx II-2, pedal ungual
II, phalanx III-1, phalanx III-2, proximal phalanx III-3, phalanx IV-1, phalanx
IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV
Diagnosis- (after Novas et al., 2010) tall and cup-like intercotylar
prominence, even more developed than in Lectavis; phalanx IV-4 anteroposteriorly
short, being subequal in length to phalanx IV-2; phalanx I-1 proportionally
short and stout.
Comments- Novas et al. (2010) described this taxon as an avisaurid most
closely related to Soroavisaurus.
Reference- Novas, Agnolin and Scanferla, 2010. New enantiornithine bird
(Aves, Ornithothoraces) from the Late Cretaceous of NW Argentina. Comptes Rendus
Palevol. 9(8), 499-503.
Bohaiornithidae Wang, Zhou, O'Connor and
Zelenkov, 2014
Definition- (Bohaiornis guoi + Shenqiornis mengi) (Wang
et al., 2014)
Diagnosis- (after Wang et al., 2014) robust rostrum; large, robust, subconical
teeth with sharply tapered and slightly distally recurved tips; pygostyle tapered,
without abrupt distal constriction; scapular blade with convex dorsal magin
and straight to weakly concave ventral margin; omal tips of furcula with blunt
expansions visible in ventrolateral view; sternum with posterolateral process
strongly projecting posterolaterally; pedal digit II more robust than other
digits; pedal unguals extremely elongated with digit III ungual measuring more
than 40% length of tarsometatarsus.
Comments- Both Chiappe et al. (2019) and Hartman et al. (2019) failed to recover this clade (as also including Sulcavis, Parabohaiornis, Zhouornis and Longusunguis) without it encompassing most enantiornithines due to the basal position of Shenqiornis in both.
References- Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine
family (Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Chiappe, Meng, Serrano, Sigurdsen, Wang, Bell and Liu, 2019. New Bohaiornis-like bird from the Early Cretaceous of China: Enantiornithine interrelationships and flight performance. PeerJ. 7:e7846.
Hartman, Mortimer, Wahl, Lomax, Lippincott and Lovelace, 2019. A new
paravian dinosaur from the Late Jurassic of North America supports a
late acquisition of avian flight. PeerJ. 7:e7247. DOI: 10.7717/peerj.7247
Beiguornis Wang, Ju, Wu, Liu, Guo and Ji, 2022
B. khinganensis Wang, Ju, Wu, Liu, Guo and Ji, 2022
Early Aptian, Early Cretaceous
Pigeon Hill, Longjiang Formation, Inner Mongolia, China
Holotype- (MHGU-F307/308)
(subadult) partial skull, eight cervical vertebrae, dorsal vertebrae,
dorsal ribs, uncinate processes, gastralia, synsacrum, five caudal
vertebrae, pygostyle, scapulae, coracoids, furcula, partial sternum,
sternal ribs, humeri, radii (one partial), ulnae (one partial),
metacarpals I, phalanges I-1, manual unguals I, carpometacarpi,
phalanges II-1, phalanges II-2, manual unguals II, phalanges III-1,
phalanx III-2, partial ilium, proximal pubis, femora, tibiae, fibula,
astragalocalcanea, metatarsal I, phalanges I-1 (one distal) pedal
unguals I, tarsometatarsi (one partial), partial phalanx II-2,
incomplete pedal ungual II, fragmentary phalanx III-1, incomplete
phalanx III-2, proximal phalanx III-3, phalanx IV-1, partial phalanx
IV-3, partial phalanx IV-4, pedal claw sheath
Diagnosis- (after Wang et al.,
2022) coracoid strongly expanded distolaterally; distal coracoid margin
long and straight; anterior margin of sternum sharply angled at median;
small notch posterior to costal edge of sternum; posteromedial sternal
processes triangular; manual ungual I long and curved; manual ungual II
short and robust.
Comments- The interpretation of
preserved pedal phalanges here is slightly different than in Wang et
al.'s (2022) figure 10, in that III-3 and pedal ungual III are viewed
as III-2 and III-3, and IV-4 and pedal ungual IV are viewed as IV-3 and
IV-4 . This is based on length in typical enantiornithines, as
phalangeal morphology is largely indeterminate due to a lack of
preparation.
Wang et al. (2022) add the taxon to O'Connor's bird analysis and find it emerges sister to Sulcavis within Bohaiornithidae.
Reference- Wang, Ju, Wu, Liu,
Guo and Ji, 2022. The first enantiornithine bird from the Lower
Cretaceous Longjiang Formation in the Great Khingan Range of Inner
Mongolia. Acta Geologica Sinica. 96(2), 337-348.
Shenqiornis Wang, O'Connor, Zhao,
Chiappe, Gao and Cheng, 2010
= Dalianornis" O'Connor, Chiappe and Bell, 2011
S. mengi Wang, O'Connor, Zhao, Chiappe, Gao and Cheng, 2010
= "Dalianornis mengi" O'Connor, Chiappe and Bell, 2011
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China
Holotype- (DNHM D2950-2951) (subadult) incomplete skull (~41.8 mm), sclerotic
plates, incomplete mandibles, atlas axis, five cervical vertebrae, three cervical
ribs, three dorsal vertebrae, dorsal ribs, several gastralia, synsacrum (23.4
mm), caudal vertebra, scapulae (39.3, ~34.6 mm), coracoids (one incomplete;
26.2 mm), furcula (28.9 mm), partial sternum (~28.8 mm), sternal ribs, humeri
(one proximal; 46.6, 43 mm), radii (one incomplete; 45.8, 39.6 mm), ulnae (46.8,
44.8 mm), proximal carpal, semilunate carpal, distal carpal III, metacarpals
I (4.5, ~4.1 mm), phalanges I-1 (10 mm), manual unguals I (5.9, ~4 mm), metacarpals
II (21.7, ~16.8 mm), phalanges II-1 (11.1, 10.1 mm), phalanges II-2 (8.7, 8.4
mm), manual unguals II (5.5, 4.7 mm), metacarpals III (20.7, ~18.4 mm), phalanx
III-1 (6.9, ~4.4 mm), ?phalanx III-2, partial ilia (~27 mm), pubes (33.4, 35
mm), ischia (17.5, 18 mm), incomplete femur (~38.8 mm), incomplete tibia, astragalocalcaneum,
distal tarsal, metatarsal I (7 mm), phalanx I-1 (7 mm), tarsometatarsi (~24.8,
25 mm; mtII ~22.4, mtIII 25, mtIV 22.8 mm), phalanx II-1 (5.6 mm), phalanx II-2
(~7.8 mm), phalanx III-1 (~8.4 mm), phalanx IV-1 (4.1 mm), phalanx IV-2, phalanx
IV-3, pedal phalanx, two pedal unguals, body feathers, two remiges
Diagnosis- (after Wang et al., 2010) narrow nasal lacking subnarial process;
postorbital with elongate, straight ventral process; robust teeth with circular
sections and slightly recurved apices; omal tips of furcula expanded; distal
third of coracoid laterally convex; posterolateral sternal process expanded
distally and fan-shaped; unreduced and unfused manus with unguals on digits
I and II; dorsally projecting tubercle on posterodorsal surface of semilunate
carpal; pubic boot present; strap-like ischium without obturator process; J-shaped
metatarsal I lacking lateral compression, with lateral facet for metatarsal
II and posterior facet for phalanx I-1.
Comments- This specimen was discovered before 2009 and used in O'Connor's
(2009) thesis. O'Connor et al. (2011) listed it as "Dalianornis mengi"
in their data matrix, though as Shenquiornis is used in the main article
and cladogram, the matrix was probably created before it was officially named
and mistakenly made it through publication. Many of the characters listed in
the diagnosis are common in enantiornithines, and the unfused carpometacarpus
is probably ontogenetic.
References- O'Connor, 2009. A systematic review of Enantiornithes (Aves:
Ornithothoraces). PhD Thesis. University of Southern California. 586 pp.
Wang, O'Connor, Zhao, Chiappe, Gao and Cheng, 2010. New species of Enantiornithes
(Aves: Ornithothoraces) from the Qiaotau Formation in Northern Hebei, China.
Acta Geologica Sinica. 84(2), 247-256.
O'Connor, Chiappe and Bell, 2011. Pre-modern birds: Avian divergences in the
Mesozoic. in Dyke and Kaiser (eds.). Living Dinosaurs: The Evolutionary History
of Modern Birds. 39-114.
O'Connor, Zhang, Chiappe, Meng, Li and Liu, 2013. A new enantiornithine from
the Yixian Formation with the first recognized avian enamel specialization.
Journal of Vertebrate Paleontology. 33(1), 1-12.
Sulcavis O'Connor, Zhang, Chiappe,
Meng, Li and Liu, 2013
S. geeorum O'Connor, Zhang, Chiappe, Meng, Li and Liu, 2013
Barremian-Aptian, Early Cretaceous
Yixian Formation, Liaoning, China
Holotype- (BMNHC Ph 000805) (171 g) incomplete skull, sclerotic plates, partial
mandibles, incomplete hyoids, seven cervical vertebrae, posterior cervical ribs,
about ten fragmentary dorsal vertrebrae, incomplete dorsal ribs, gastralial
fragments, synsacrum (19.3 mm), six caudal vertebrae, pygostyle (19.6 mm), chevrons,
incomplete scapulae (34.9 mm), incomplete coracoids (24.8 mm), incomplete furcula,
sternla? fragments, sternal ribs, humeri (46.5 mm), radii (one incomplete; 47.7
mm), ulnae (one incomplete; 51.1 mm), scapholunare, pisiform, metacarpals I (one partial),
phalanges I-1 (one partial), manual ungual I, carpometacapri (one incomplete),
phalanx II-1, phalanx II-2, manual ungual II, manual claw sheaths, phalanx III-1,
manual fragments, ilia (one partial; 26.5 mm), partial pubis, ischial fragment,
femora (41.3 mm), tibiae (47.3 mm), incomplete fibulae (18.9 mm), astragalocalcanea,
metatarsals I (5 mm), phalanges I-1, pedal unguals I, tarsometatarsi (24.85
mm- II 21.6 mm, III 24.3 mm, IV 22.6 mm), phalanges II-1, phalanges II-2, pedal
unguals II, phalanx III-1, phalanx III-2, pahlanx III-3, pedal ungual III, phalanx
IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal claw
sheaths, feathers
Diagnosis- (after O'Connor et al., 2012) broad nasal with short, tapered,
anteriorly directed maxillary process; robust teeth with caudally recurved apices,
D-shaped cross-section with flat lingual margin, and lingual face with longitudinal
grooves radiating from the occlusal tip; posteriormost transverse processes
of synsacrum extending far beyond the posterior articular surface of their respective
centra; scapula with long and delicate acromion process; convex lateral margin
of the coracoid; medial angle of coracoid expanded; Y-shaped furcula with blunt
omal apices; alular claw larger than that of the major digit; pedal digit II
hypertrophied; deep pits for the collateral ligament and lateral ridges present
on pedal unguals.
Reference- O'Connor, Zhang, Chiappe, Meng, Li and Liu, 2013. A new enantiornithine
from the Yixian Formation with the first recognized avian enamel specialization.
Journal of Vertebrate Paleontology. 33(1), 1-12.
Zhouornis Zhang, Chiappe, Han and
Chinsamy, 2013
Z. hani Zhang, Chiappe, Han and Chinsamy, 2013
Barremian-Albian, Early Cretaceous
Jehol Group, Liaoning, China
Holotype- (CNUVB-0903) (227 g, subadult) skull (~35 mm), partial mandible, altas,
axis, third cervical vertebra, fourth cervical vertebra, fifth cervical vertebra,
sixth cervical vertebra, seventh cervical vertebra, eighth cervical vertebra,
cervical ribs, nine dorsal vertebrae, dorsal ribs, gastralia, synsacrum, caudal
vertebrae, pygostyle (17.3 mm), scapulae (40.7, 40.4 mm), coracoids (28.4, 28.3
mm), furcula, sternum, sternal ribs, humeri (50.6, 50.6 mm), radii, ulnae (53.5,
54 mm), scapholunares, pisiforms, carpometacarpi (mcI 4.1, 3.7 mm; 23.6, 24.4 mm),
phalanges I-1 (9.1, 9.1 mm), manual unguals I (4.6, 5.0 mm), phalanges II-1
(10.8, 10.6 mm), phalanges II-2 (8.1, 7.5 mm), manual unguals II (4.9, 3.7 mm),
phalanges III-1 (5.6, 5.6 mm), manual claw sheaths, partial ilia, pubes, femora
(44.5, 43.5 mm), tibiotarsi (52.1, 51.2 mm), fibulae, metatarsals I, phalanges
I-1 (6.3, 6.5 mm), pedal unguals I (8, 8.8 mm), tarsometatarsi (26.1, 25.8 mm),
phalanges II-1 (6.3, 7.2 mm), phalanges II-2 (8.3, 8.8 mm), pedal unguals II
(10.1, 11.2 mm), phalanges III-1 (7.7 mm), phalanges III-2 (7.1, 6.9 mm), phalanges
III-3 (7.1, 6.8 mm), pedal unguals III (10.1, 10.2 mm), phalanx IV-1 (4.2 mm),
phalanx IV-2 (4 mm), phalanx IV-3 (3.3 mm), phalanges IV-4 (4.3 mm), pedal unguals
IV (7, 7.2 mm), pedal claw sheaths, body feathers remiges
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Referred- (BMNHC Ph 756) (137 g, subadult) skull, mandibles, hyoids, six or
seven cervical vertebrae, cervical ribs, three dorsal vertebrae, dorsal ribs,
uncinate process, gastralia, synsacrum, four or five caudal vertebrae, pygostyle
(22.4 mm), scapulae (32.4, 36 mm), coracoids (20.9, 23.1 mm), partial furcula,
sternum, sternal ribs, incomplete humeri (38.3, 40.5 mm), incomplete radii,
ulnae (one incomplete; 36.9, 41.5 mm), scapholunares, pisiforms, (carpometacarpi 19.3,
19.5 mm) semilunate carpals, metacarpals I, phalanges I-1 (one partial), manual
unguals I (one fragmentary), metacarpals II, phalanges II-1, phalanges II-2,
manual unguals II, manual claw sheaths, metacarpals III, phalanges III-1, incomplete
ilium, incomplete pubes, ischium, femora (31.4, 26.4 mm), tibiotarsi (one partial;
39.3, 41.7 mm), partial fibulae, metatarsals I, phalanges I-1, pedal unguals
I, tarsometatarsi (22.5, 20 mm), phalanges II-1, phalanges II-2, pedal unguals
II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges
IV-1, phalanges IV-2, phalanges IV-3 (one partial), phalanx IV-4, pedal unguals
IV, pedal claw sheaths, feathers (Zhang et al., 2014)
Diagnosis- (after Zhang et al., 2013) bifurcated posterior end of maxillary
process of premaxilla; oval maxillary fenestra; large paraoccipital processes;
long basipterygoid processes; axis with short epipophyses; scapula with curved
blade; coracoid displaying longitudinal dorsal trough that extends through omal
half of bone; sternum bearing pair of long, robust lateral processes with triangular,
posteromedially slanting distal end, and angular anterolateral corners; humeral
head proximally flat.
Comments- The holotype was acquired from a farmer, making locality information
uncertain.
References- Zhang, Chiappe, Han and Chinsamy, 2013. A large bird from
the Early Cretaceous of China: New information on the skull of enantiornithines.
Journal of Vertebrate Paleontology. 33(5), 1176-1189.
Zhang, O'Connor, Liu, Meng, Sigurdsen and Chiappe, 2014. New information on
the anatomy of the Chinese Early Cretaceous Bohaiornithidae (Aves: Enantiornithes)
from a subadult specimen of Zhouornis hani. PeerJ. 2, e407.
Longusunguis Wang, Zhou,
O'Connor and Zelenkov, 2014
L. kurochkini Wang, Zhou, O'Connor and Zelenkov, 2014
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V17964) (130 g, subadult) partial skull (~33.9 mm), mandibles,
partial hyoids, six cervical vertebrae, elevan dorsal vertebrae, partial dorsal
ribs, synsacrum, seven caudal vertebrae, chevrons, pygostyle (22.8 mm), scapulae
(34.7 mm), coracoid (24.2 mm), furcula, sternum (31.1 mm), furcula, humeri (40.3
mm), radii (40.5 mm), ulnae (one incomplete; 43.6 mm), scapholunares, pisiforms, semilunate
carpals, metacarpals I (3.6 mm), incomplete phalanges I-1 (7.1 mm), manual ungual
I (4.5 mm), metacarpals II (16.8 mm), phalnges II-1 (one fragmentary; 10.5 mm),
phalanx II-2 (6.9 mm), manual ungual II (~3.4 mm), metacarpals III (18 mm),
phalanges III-1 (one partial; 5.2 mm), partial ilia, pubes (one partial; 29.1
mm), ischia (one partial; 17 mm), femora (one incomplete; 35.8 mm), tibiae (one
incomplete; 41.8 mm), fibula, astragalocalcanea, distal tarsal IV, metatarsal
I, phalanx I-1 (5.4 mm), metatarsals II (19.6 mm), phalanges II-1 (5.4 mm),
phalanges II-2 (7.2 mm), pedal unguals II, metatarsals III (21.4 mm), phalanges
III-1 (7 mm), phalanges III-2 (6.4 mm), phalanx III-3 (6.7 mm), pedal ungual
III (12 mm), metatarsal IV (20.2 mm), phalanx IV-1 (3.7 mm), phalanx IV-2 (2.9
mm), phalanx IV-3 (3.4 mm), phalanx IV-4 (4.6 mm), body feathers, retrices or
leg remiges
Diagnosis- (after Wang et al., 2014) maxilla with fenestra on posterior
process; ventral process of lacrimal with elongate excavation on posterior margin;
pygostyle longer than tarsometatarsus; lateral margin of coracoid more convex
than other bohaiornithids; acromion strongly projecting dorsally.
Reference- Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine
family (Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Parabohaiornis Wang, Zhou,
O'Connor and Zelenkov, 2014
P. martini Wang, Zhou, O'Connor and Zelenkov, 2014
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype-
(IVPP V18691) (subadult) incomplete skull (42.5 mm), incomplete
mandibles, partial hyoids, eight cervical vertebrae, eleven dorsal
vertebrae, dorsal ribs, uncinate processes, gastralia, synsacrum, four
caudal vertebrae, pygostyle (18 mm), scapula (33.3 mm), coracoid (21.9
mm), furcula, partial sternum, sternal ribs, humeri (43.4 mm), radii
(40.3 mm), ulnae (43.8 mm), scapholunares, pisiforms, semilunate
carpals, metacarpals I (3.9 mm), phalanges I-1 (8.1 mm), manual unguals
I (3.5 mm), metacarpals II (16.5 mm), phalanges II-1 (10.2 mm),
phalanges II-2 (7.4 mm), manual unguals II (3.2 mm), metacarpals III
(17.6 mm), phalanges III-1 (5.5 mm), ilia (23.7 mm), pubes (31 mm),
ischia (one partial; 20.3 mm), femora (36 mm), tibiae (40 mm), fibulae,
astragalocalcaneum, distal tarsal III, metatarsals I, phalanges I-1
(5.4 mm), pedal unguals I (6 mm), metatarsals II (17.1 mm), phalanges
II-1 (4.5 mm), phalanges II-2 (6.8 mm), pedal unguals II (8.7 mm),
metatarsals III (19.5 mm), phalanges III-1 (6.4 mm), phalanges III-2
(5.4 mm), phalanges III-3 (5.3 mm), pedal unguals III (8.8 mm),
metatarsals IV (18.1 mm), phalanges IV-1 (2.9 mm), phalanges IV-2 (2.6
mm), phalanges IV-3 (2.9 mm), phalanges IV-4 (4.1 mm), pedal unguals IV
(~4.7 mm)
Paratype- (IVPP V18690) (subadult) few cervical vertebrae, seven dorsal
vertebrae, dorsal ribs, uncinate processes, gastralia, synsacrum, six caudal
vertebrae, pygostyle (21.8 mm), scapulae (one partial; one incomplete), coracoids
(one incomplete; 25.6 mm), incomplete furcula, incomplete sternum, sternal ribs,
humeri (one incomplete; 46.7 mm), incomplete ilia (24.4 mm), pubes (32 mm),
ischia (20.8 mm), femora (37.5 mm), tibiotarsi (45 mm), fibulae, distal tarsal
III, metatarsals I, phalanges I-1 (6.1 mm), pedal unguals I (~6.3 mm), metatarsals
II (20.4 mm), phalanges II-1 (5.8 mm), phalanges II-2 (7.6 mm), pedal unguals
II (10 mm), metatarsals III (22 mm), phalanges III-1 (7.8 mm), phalanges III-2
(6.5 mm), phalanges III-3 (6.6 mm), pedal unguals III (11.5 mm), metatarsals
IV (20.6 mm), phalanges IV-1 (2.9 mm), phalanges IV-2 (2.6 mm), phalanges IV-3
(2.9 mm), phalanges IV-4 (4.4 mm), pedal unguals IV (7 mm), pedal claw sheaths
Diagnosis- (after Wang et al., 2014) three premaxillary teeth; four maxillary
teeth; nasal without anteroventral process; intercondylar incisure absent on
tibiotarsus; acromion parallel to scapular shaft; length ratio of pygostyle
to metatarsal III 0.92-0.99; pedal phalanx IV-1 <70% length of IV-4.
Reference- Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine
family (Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Bohaiornis Hu, Li, Hou and Xu, 2011
= "Bohaiornis" Hu, Hou and Xu, 2009
B. guoi Hu, Li, Hou and Xu, 2011
= "Bohaiornis guoi" Hu, Hou and Xu, 2009
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (LPM B00167) (296 mm; subadult) incomplete skull (~47 mm), sclerotic
plates, mandibles (38 mm), hyoid, axis, third cervical vertebra, fourth cervical
vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh cervical
vertebra, eighth cervical vertebra, ninth cervical vertebra, tenth cervical
vertebra, eleventh cervical vertebra, cervical ribs, seven dorsal vertebrae,
dorsal ribs, gastralia, synsacrum, six caudal vertebrae, pygostyle, scapulae,
coracoids (23 mm), furcula (24 mm), sternum (36.4 mm), sternal ribs, humerus
(47 mm), radii (45.4 mm), ulnae (48 mm), scapholunare, pisiforms, semilunate carpals,
metacarpals I (8 mm), phalanges I-1 (9.5 mm), manual unguals I (4.5 mm), metacarpals
II (21.3 mm), phalanges II-1 (10.8 mm), phalanges II-2 (7.5 mm), manual unguals
II (3.6 mm), metacarpals III (22.7 mm), phalanx III-1 (5.5 mm), ilium (25.6
mm), pubes (33 mm), ischia (21 mm), femora (39 mm), tibiae (46 mm), fibulae
(23 mm), astragalocalcaneum, distal tarsal, metatarsals I (5.7 mm), phalanges
I-1 (6 mm), pedal unguals I (9 mm), metatarsals II (20.8 mm), phalanges II-1
(5 mm), phalanges II-2 (7 mm), pedal unguals II (12 mm), metatarsals III (one
partial; 22.5 mm), phalanges III-1 (7.6 mm), phalanges III-2 (7.2 mm), phalanges
III-3 (6.5 mm), pedal unguals III (10.3 mm), metatarsals IV (one distal; 21.8
mm), phalanges IV-1 (4 mm), phalanges IV-2 (3.3 mm), phalanges IV-3 (3.5 mm),
phalanges IV-4 (4.2 mm), pedal unguals IV (7.5 mm), remiges, retrices
Referred- (IVPP V17963) (adult) skull (45.3 mm), sclerotic plates, mandibles,
seven cervical vertebrae, four dorsal vertebrae, dorsal ribs, gastralia, synsacrum,
six caudal vertebrae, pygostyle (19.2 mm), scapulae (one partial; ~33.9 mm),
coracoids (25.9, ~22.6 mm), furcula, incomplete sternum (36.2 mm), sternal ribs,
humeri (50.3 mm), radii (48.8 mm), ulnae (53mm), scapholunare, pisiform, carpometacarpi
(~23.3; mcI 4, mcII 22.8, mcIII ~21 mm), phalanges I-1 (9.3 mm), manual unguals
I (5.1 mm), phalanges II-1 (11.1 mm), phalanges II-2 (7 mm), manual unguals
II (3.4 mm), phalanges III-1 (6.7 mm), incomplete ilium (24.2 mm), proximal
pubes, proximal ischium, femora (42.6 mm), tibiotarsi (49.4 mm), metatarsals
I, phalanges I-1, pedal ungual I, tarsometatarsi (~22.7 mm), phalanx II-1 (6.1
mm), phalanx II-2 (8.1 mm), pedal unguals II (10.2 mm), phalanx III-1, phalanges
III-2 (6.5 mm), phalanges III-3 (6.6 mm), pedal unguals III (one fragmentary;
10.5 mm), phalanges IV-1 (3.8 mm), phalanges IV-2 (3.5 mm), phalanges IV-3 (3.2
mm), phalanges IV-4 (4.4 mm), pedal unguals IV (8.7 mm), pedal claw sheaths,
gastroliths (Li et al., 2014)
Diagnosis- (after Hu et al., 2009) sacral centra strongly compressed
transversely; clavicular ramus of furcula straight; clavicular facet with a
transversely expanded proximal end; prominent ridge along medioventral margin
of clavicular ramus of furcula.
(after Hu et al., 2011) posterior end of the articular pointed posteroventrally.
(after Li et al., 2014) strap-like and faintly ventrally recurved jugal bar;
reduced maxillary and dentary dentition; robust teeth; broad scleral ossicles;
acromion developed as a rectangular process with a broadly expanded tip; slightly
medially hooked acrocoracoid; glenoid facet on coracoid positioned at approximately
the same level as acrocoracoid process; flat to sub-concave lateral margin of
the coracoid with small lateral process; sternal midline with slightly developed
T-shaped terminus approximately equal in posterior extent to posterolateral
process; elongate, strongly recurved pedal unguals; third pedal ungual larger
but less recurved than other pedal unguals.
Other diagnoses- Hu et al. (2009) state the presence of cervical centra
with strong ventral keels is unique, but this is shared with most other enantiornithines
except Pengornis. The long acromion is also present in Eoalulavis.
Comments- Hu et al. (2009) briefly describe this new taxon in their SVP
abstract, which made it a nomen nudum according to ICZN Article 9.9. They later
described it officially in 2011.
Although Hu et al. believed the holotype to be from the Yixian Formation, Li
et al. (2014) described a specimen from near the same village which was found
in the Jiufotang Formation. As their fieldwork found most of the exposures there
to be Jiufotang, so believe the holotype was from that formation too.
While the authors state Bohaiornis strongly resembles Eoenantiornis
in several characters (short and deep skull with six to seven teeth on each
side of upper and lower jaws; forelimbs subequal to hindlimbs in length; manual
digit I with robust and curved ungual extending distally to the level of the
distal end of metacarpal II), only the short and deep skull is potentially synapomorphic.
Their 2009 phylogenetic analysis found Bohaiornis to be more derived
than Protopteryx, but more basal than most other enantiornithines including
Eoenantiornis. Their 2011 phylogenetic analysis is a version of the Elsornis
analysis with eight added characters and finds Bohaiornis in a polytomy
with other non-longipterygid enantiornithines. Li et al. (2014) used a version
of Clarke's analysis to find Bohaiornis more derived than Protopteryx,
but outside Longipterygidae and a clade of Cathayornis, Concornis,
Gobipteryx and Neuquenornis.
References- Hu, Hou and Xu, 2009. A new enantiornithine bird from the
Lower Cretaceous of Western Liaoning, China. Journal of Vertebrate Paleontology.
29(3), 118A.
Hu, Li, Hou and Xu, 2011. A new enantiornithine bird from the Lower Cretaceous
of Western Liaoning, China. Journal of Vertebrate Paleontology. 31(1), 154-161.
Li, Zhou and Clarke, 2012. A large-bodied basal enantiornithine bird from the
Early Cretaceous of China with a proposed raptorial feeding ecology. Journal
of Vertebrate Paleontology. Program and Abstracts 2012, 127.
Li, Zhou, Wang and Clarke, 2014. A new specimen of large-bodied basal enantiornithine
Bohaiornis from the Early Cretaceous of China and the inference of feeding
ecology in Mesozoic birds. Journal of Paleontology. 88(1), 99-108.
Wang, Zhou, O'Connor and Zelenkov, 2014. A new diverse enantiornithine family
(Bohaiornithidae fam. nov.) from the Lower Cretaceous of China with information
from two new species. Vertebrata PalAsiatica. 52(1), 31-76.
Liaoningornithiformes Hou, 1996
Liaoningornithidae Hou, 1996
Diagnosis- (proposed) sternum elongate (unknown in Vorona); posteromedial
sternal processes absent (also in taxa less derived than Longipteryx;
unknown in Vorona); posterolateral sternal processes absent (unknown
in Vorona); posteromedian process of sternum extremely expanded (unknown
in Vorona); metatarsals at least partially fused distally (also in Changchengornis,
Avisaurus gloriae and Euornithes; unknown in Eoalulavis); trochlea
of metatarsal II subequal in width to III (also in non-enantiornithines and
Longipterygidae; unknown in Eoalulavis); metatarsal IV not reduced in
width compared to II and III (also in non-enantiornithines and those more basal
than Longipteryx; unknown in Eoalulavis).
Reference- Hou, 1996. The discovery of a Jurassic carinate bird in China.
Chinese Science Bulletin. 41(2), 1861-1864.
Eoalulavis Sanz, Chiappe, Perez-Moreno,
Buscalioni, Moratalla, Ortega and Poyato-Ariza, 1996
E. hoyasi Sanz, Chiappe, Perez-Moreno, Buscalioni, Moratalla,
Ortega and Poyato-Ariza, 1996
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Holotype- (LH-13500) (~150 mm; 45 g, adult) five posterior cervical vertebrae,
ten dorsal vertebrae, several dorsal ribs, scapulae, coracoids (17 mm), furcula,
sternum, humeri (27 mm), radii, ulnae (31 mm), pisiform, metacarpal I, phalanx
I-1, manual ungual I, metacarpal II, phalanx II-1, phalanx II-2, manual ungual
II, metacarpal III, phalanx III-1, ilium, proximal femur, feather impressions
References- Sanz, Chiappe, Perez-Moreno, Buscalioni, Moratalla, Ortega
and Poyato-Ariza, 1996. An Early Cretaceous bird from Spain and its implications
for the evolution of avian flight. Nature. 382, 442-445.
Sanz, P�rez-Moreno, Chiappe and Buscalioni, 2002. The Birds from the
Lower Cretaceous of Las Hoyas (Privince of Cuenca, Spain). pp 209-229. in Chiappe
and Witmer (eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London.
Liaoningornis Hou, 1996
L. longidigitus Hou, 1996
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V11303) (~150 mm) several partial dorsal ribs, gastralia,
partial scapula or pubis, partial coracoid, sternum, few sternal ribs, partial
furcula, distal humerus, incomplete radius, incomplete ulna, femur, tibiotarsus,
fibula, metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi, phalanges
II-1, phalanges II-2, pedal ungual II, phalanges III-1, phalanges III-2, phalanges
III-3, pedal unguals III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx
IV-4, pedal ungual IV, body feathers
Diagnosis- (after O'Connor, 2012) small, imperforate sternum without
posterolateral or posteromedial processes; T-shaped posteromedian process; anteriorly
forked, ventrally projecting sternal keel that does no extend to anterior margin;
sternal keel low distally and continuous with posteromedian process; femorotibiotarsal
ratio 82%; metatarsal I P-shaped with nearly parallel articular surfaces; large,
curved pedal unguals.
Comments- This specimen has a number of controversial element identifications.
An element identified as a scapula by Hou (1997) was identified as a pubis by
Zhou and Hou (2002) and later as two dorsal ribs by O'Connor (2012). Another
pubis identified by Zhou and Hou was unlabeled in Hou (1997), and identified
as more dorsal ribs by O'Connor. The coracoid is interpreted as laying with
its lateral edge against the sternum by Hou, but with its distal edge against
the sternum in articulation by Zhou and Hou and O'Connor. Finally, an elongate
bone was identified as a hypocleidium by Hou, but as part of the sternal keel
by Zhou and Hou. Clarke (2002) and O'Connor agree with the former identification.
While initially identified as an euornithine (hiss Ornithurae) by Hou (1996) and most later
non-cladistic studies, Clarke (2002), O'Connor et al. (2010) and O'Connor (2012)
found it to be enantiornithine, the latter emphasizing the similarity of its
sternum to Eoalulavis.
References- Hou, 1996. The discovery of a Jurassic carinate bird in China.
Chinese Science Bulletin. 41(2), 1861-1864.
Hou, Martin, Zhou and Feduccia, 1996. Early adaptive radiation of birds: Evidence
from fossils from northeastern China. Science. 274, 1164-1167.
Hou, 1997. A carinate bird from the Upper Jurassic of western Liaoning, China.
Chinese Science Bulletin. 42(5), 413-417.
Hou, 1997. Mesozoic Birds of China. Phoenix Valley Bird Park.
221 pp.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh
and the phylogenetic relationships of basal Ornithurae. PhD thesis. Yale University,
New Haven, CT. 532 pp.
Zhou and Hou, 2002. The discovery and study of Mesozoic birds in China. In Chiappe
and Witmer (eds.). Mesozoic Birds - Above the Heads of Dinosaurs. University
of California Press, Berkeley, Los Angeles, London. 160-183.
O'Connor, Zhou and Zhang, 2010. A new look at 'old' birds from the Jehol fauna.
Journal of Vertebrate Paleontology. Program and Abstracts 2010, 141A.
O'Connor, 2012. A revised look at Liaoningornis longidigitrus (Aves).
Vertebrata PalAsiatica. 50(1), 25-37.
Vorones Zelenkov in Zelenkov and Kurochkin, 2015
Definition- (Vorona berivotrensis <- Gobipteryx minuta, Passer domesticus) (Zelenkov and Kurochkin, 2015)
Voroniformes Zelenkov in Zelenkov and Kurochkin, 2015
Comments- Vorones was named by
Zelenkov in a Russian book chapter by Zelenkov and Kurochkin (2015) as
a parvclass of euornithines (their Ornithurae) including Vorona, Mystiornis, Hollanda and Patagopteryx, each given their own order and family. Their definition of (translated) "birds that are more related to Vorona berivotrensis Forster et al., 1996 than Passer domesticus (Linnaeus, 1758) or Gobipteryx minuta Elzanowski, 1974". Given a placement of Vorona
deeply nested within Enantiornithes as on this site, that definition
could cover a large number of enantiornithine genera depending on the
position of Gobipteryx.
Reference- Zelenkov and Kurochkin, 2015. Class Aves. In Kurochkin, Lopatin and
Zelenkov (eds.). Fossil vertebrates of Russia and adjacent countries.
Part 3. Fossil Reptiles and Birds. GEOS. 86-290.
Vorona Forster, Chiappe, Krause
and Sampson, 1996
V. berivotrensis Forster, Chiappe, Krause and Sampson, 1996
Maastrichtian, Late Cretaceous
Maevarano Formation, Madagascar
Holotype- (UA 8651) (~510 mm) distal tibiotarsus, tarsometatarsus (60.9
mm; metatarsal II 53.8 mm, metatarsal III 61 mm, metatarsal IV 58.4 mm, metatarsal
V 16.4 mm)
Paratype- (FMNH PA 715) (~540 mm) incomplete femur (93.7 mm), tibiotarsus
(165.8 mm), incomplete fibula
Referred- (FMNH PA 717) incomplete femur (94.1 mm) (Forster et al., 2002)
?(FMNH PA 743) proximal humerus (Forster and O'Connor, 2000; described by O'Connor
and Forster, 2010)
?(FMNH PA 744) partial humerus (~120 mm) (Forster and O'Connor, 2000; described
by O'Connor and Forster, 2010)
?(FMNH PA 745) distal humerus (O'Connor and Forster, 2010)
?(FMNH PA 750) incomplete ulna (Forster and O'Connor, 2000; described by O'Connor
and Forster, 2010)
(FMNH PA 782) tarsometatarsus (41.9 mm) (O'Connor and Forster, 2009; described
by O'Connor and Forster, 2010)
(UA 9609) distal tibiotarsus (O'Connor and Forster, 2010)
?(UA 9749) partial humerus (O'Connor and Forster, 2010)
?(UA 9750) incomplete humerus (~79.4 mm) (O'Connor and Forster, 2010)
?(UA 9751) ulna (93.3 mm) (O'Connor and Forster, 2010)
(UA 9752) proximal tibiotarsus (O'Connor and Forster, 2009; described by O'Connor
and Forster, 2010)
Comments- Using the tibiotarsus to estimate gives a length of 690 mm,
while using the metatarsus gives a length of 460 mm. I decided to use tibial
diameter, figuring this would remain more constant in different taxa. This gives
the 540 mm estimate above, which seems appropriate. This is based off the referred
specimen, the holotype was about 6% smaller, or about 510 mm long.
Two of the humeri were stated by Forster and O'Connor (2000) to belong to Vorona,
probably FMNH PA 743 and 744 which were stated to correspond in size to Vorona
by O'Connor and Forster (2010). The three other humeri are ~80% the size, but
match in morphology. All of these are termed Humeral Taxon A by O'Connor and
Forster and show a mix of enantiornithine and euornithine anatomy as Vorona
does, so are tentatively referred to the taxon by those authors. The ulna speculated
to belong to Vorona by Forster and O'Connor (2010) is probably FMNH PA
750 due to its large size, while O'Connor and Forster added UA 9751 which is
72% the size. Finally, O'Connor and Forster (2009) noted a small tibiotarsus
and tarsometatarsus referrable to Vorona, which are UA 9752 (based on
the reference to proximal details) and FMNH PA 782 respectively, described by
O'Connor and Forster (2010) as Vorona in addition to distal tibiotarsus
UA 9609.
References- Forster, Chiappe, Krause and Sampson, 1996. The first Cretaceous
bird from Madagascar. Nature. 382, 532-534.
Forster and O'Connor, 2000. The avifauna of the Upper Cretaceous Maevarano Formation,
Madagascar. Journal of Vertebrate Paleontology. 20(3), 41A-42A.
Forster, Chiappe, Krause and Sampson, 2002. Vorona berivotrensis, a primitive
bird from the Late Cretaceous of Madagascar. In Chiappe and Witmer
(eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University of California
Press. 268-280.
O'Connor and Forster, 2009. The Late Cretaceous (Maastrichtian) avifauna from
the Maevarano Formation, northwestern Madagascar: Recent discoveries and new
insights related to avian anatomical diversification. Journal of Vertebrate
Paleontology. 29(3), 157A.
O'Connor and Forster, 2010. A Late Cretaceous (Maastrichtian) avifauna from
the Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 30(4),
1178-1201.