Aves Linnaeus, 1758
Definition- (Struthio camelus + Tinamus major + Vultur gryphus) (Gauthier and de Queiroz, 2001; modified from Gauthier, 1986)
Other definitions- (Archaeopteryx lithographica + Passer domesticus) (Sereno, in press; modified from Chiappe, 1992)
(Struthio camelus + Vultur gryphus) (modified from Kischlat and Timm, 2006)
= Neornithes Gadow, 1892
Definition- (Struthio camelus + Passer domesticus) (Sereno, in press; modified from Sereno, 1998)
Other definitions- crown(Passer domesticus <- Crocodylus niloticus) (Sereno, 2004)
Diagnosis- (proposed) maxilla toothless (unknown in Ambiortidae; also in Archaeorhynchus); premaxilla extends more than half of facial margin (unknown in Ambiortidae); dorsal maxillary process absent or with no lateral exposure (unknown in Ambiortidae); no dorsal projection of maxilla participates in anterior margin of the antorbital fenestra (unknown in Ambiortidae); quadrate with posterior condyle distally (unknown in Ambiortidae; also in Patagopteryx); palatine contacts premaxilla (unknown in Ambiortidae); pterygoid surface for basisphenoid articulation in line with axis of pterygoid (unknown in Ambiortidae); dentary symphyseal foramina opening on posterior edge of symphysis (unknown in other ornithuromorphs more derived than Songlingornithidae); all presacral vertebrae heterocoelous (also in Hesperornithes); fourteen or more sacral vertebrae (also in Hesperornis regalis); series of short sacral vertebrae, with dorsally directed parapophyses just anterior to the acetabulum (also in Gansus and Ichthyornis); coracoid pneumatized (unknown in Ambiortidae); pneumatic foramina between costal articulations in sternum (unknown in Ambiortidae); paired intermuscular ridges on sternum (unknown in Ambiortidae; also in Gansus); transverse groove absent on humerus; deltopectoral crest projected anteriorly (also in Patagopterygidae and Longicrusavis); deltopectoral crest reduced in height (also in derived hesperornithines and Patagopteryx); bicipital crest not projected; pneumatic foramina in humerus; V-shaped ulnare (also in Ichthyornis); tip of extensor process conspicuously surpasses articular facet by approximately half the width of facet, producing a pronounced knob; intermetacarpal space terminates distal to end of metacarpal I (also in Gansus); metacarpal III extends distal to metacarpal II; preacetabular process overlaps a pair of dorsal ribs (also in Gansus); intercotylar prominence well developed (also in derived hesperornithines and Ichthyornis); hypotarsus with crests and grooves;

incertae sedis

Apatornithiformes Martin, 1991
Apatornithidae Furbringer, 1888
Apatornis Marsh, 1873b
Definition- (Apatornis celer <- Ichthyornis dispar, Struthio camelus, Tetrao major, Vultur gryphus) (modified from Clarke, 2004)
= Iaceornis sensu Clarke, 2004
Definition- (YPM 1451 <- Ichthyornis dispar, Struthio camelus, Tetrao major, Vultur gryphus)
Comments- Clarke (2004) accidentally defined Iaceornis identically to Apatornis.
Brodkorb (1963) referred Cimolopteryx retusus to Apatornis, but transferred it to a new genus Palintropus in 1970.
References- Marsh, 1873b. On a new sub-class of fossil birds (Odontornithes). American Journal of Science, 3rd series. 5, 161-162.
Furbringer, 1888. Untersuchungeb zur Morphologie und Systematik der Vogel. Amsterdam: Holkema, 1751 pp.
Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. In Sibley, Hickey and Hickey (eds). Proceedings of the XIII International Ornithological Congress. 55-70.
Brodkorb, 1970. The generic position of a Cretaceous bird. Quarterly Journal of the Florida Academy of Science. 32(3), 239-240.
Martin, 1991. Mesozoic birds and the origin of birds. in Schultze and Trueb (eds). Origins of the Higher Groups of Tetrapods: Controversy and Consensus. 485-540.
Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural History. 286: 1-179.
A. celer (Marsh, 1873a) Marsh, 1873b
Definition- (the species that includes YPM 1451) (Clarke, 2004)
= Ichthyornis celer Marsh, 1873a
Early Campanian, Late Cretaceous
Hesperornis Zone of the Smoky Hill Chalk Member of the Niobrara Formation, Kansas, US

Holotype- (YPM 1451) posterior synsacrum
Other diagnoses- Marsh (1873a) originally diagnosed Ichthyornis celer by contrasting it to Ichthyornis dispar. He stated it was larger, but this doesn't seem to be the case and he changed his mind by 1875. Marsh also stated the synsacrum was more slender than I. dispar, with a more concave posterior articular surface, but Clarke (2004) noted these differences don't seem to exist. Shufeldt (1915) noted the slender appearence was due to transverse crushing and a broken ventral edge.
Marsh (1880) later proposed additional differences from Ichthyornis. The synsacrum must contain at least one additional vertebra than the ten seen in the I. dispar holotype, but a specimen referred to I. victor (YPM 1732) has twelve vertebrae, and Aves basally have more vertebrae than the I. dispar holotype too. The presence of four mid sacral vertebrae with dorsally directed transverse processes (as opposed to Ichthyornis' three) is also seen in most Aves. Finally, Apatornis differs in lacking ossified tendons on its sacral vertebrae, but this is a plesiomorphy shared by almost all non-avian theropods.
Comments- The holotype was discovered in 1872 and described by Marsh (1873a) as a new species of Ichthyornis. He placed it in a new genus later that year without justification and described it in more detail in 1880. The partial skeleton YPM 1734 was referred to Apatornis by Marsh (1880), and most opinions on this taxon since 1880 have been based on this skeleton instead of the holotype synsacrum. Shufeldt (1915) believed the holotype belonged to a species of Ichthyornis, though without listed evidence. Howard (1955) thought the transversely narrow synsacrum which was unfused to the pelvis was similar to Telmabates (now recognized as a presbyornithid anatiform), but the sacrum is crushed transversely and the lack of fusion is primitive and also found in most Mesozoic ornithuromorphs, charadriiforms and other taxa. Martin (1987) described cervical and humeral characters of Apatornis, but these elements are not preserved in the holotype or YPM 1734. Elzanowski (1995) and Hope (2002) noted the problem that YPM 1734 was not comparable with the type, which was solved when Clarke (2002, 2004) separated the skeleton as the new taxon Iaceornis marshi. Clarke found Apatornis to be more derived than Ichthyornis based on the presence of four or more sacrals with dorsally directed transverse processes, but less derived than Aves due to the presence of thirteen or less sacrals. However, a similarly low number of sacral vertebrae is present in many avians, including many procellariiforms, charadriiforms and most of the 'higher land birds'. As Clarke did not include any neoavians in her analysis, it seems possible Apatornis could belong to that clade.
References- Marsh, 1873a. Notice of a new species of Ichthyornis. American Journal of Science, 3rd series. 5, 74.
Marsh, 1873b. On a new sub-class of fossil birds (Odontornithes). American Journal of Science, 3rd series. 5, 161-162.
Marsh, 1875a. On the Odontornithes, or birds with teeth. American Journal of Science, Series 3. 10(59), 403-408.
Marsh, 1875b. Odontornithes, or birds with teeth. The American Naturalist. 9(12), 625-631.
Marsh, 1880. Odontornithes: a monograph on the extinct toothed birds of North America. United States Geological Exploration of the 40th Parallel. Washington, DC: U.S. Government Printing Office. 201 pp.
Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences. 19, 1-110.
Howard, 1955. A new wading bird from the Eocene of Patagonia. American Museum Novitates. 1710, 25 pp.
Martin, 1987. The beginning of the modern avian radiation. Documents des Laboratoires de Geologie de la Faculte des Sciences de Lyon. 99, 9-20.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut Senckenberg. 181, 37-53.
Clarke, 1999. New information on the type material of Ichthyornis: Of chimeras, characters and current limits of phylogenetic inference. Journal of Vertebrate Paleontology. 19(3), 38A.
Clarke, 2000. Ichthyornis and Apatornis reappraised. Vertebrata PalAsiatica. 38(suppl.), 9.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural History. 286: 1-179.

Gallornis Lambrecht, 1931
G. straeleni Lambrecht, 1931
Berriasian-Hauterivian, Early Cretaceous
Auxerre, France

Holotype- (Royal Belgian Institute of Natural Sciences coll.) proximal humeral fragment, proximal femur
Comments- Lambrecht (1931) originally considered this taxon to be an anseriform intermediate between Anas and Cygnus in morphology. Hope (2002) considers this an avian based on the presence of an elevated trochanteric crest and an anteroposteriorly expanded antitrochanteric facet.
References- Lambrecht, 1931. Gallornis straeleni n. g. n. sp., ein Kreidevogel aus Frankreich. Bulletin de Musee Royal d'Histoire Naturelle de Belgique. 7, 1-6.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Iaceornis Clarke, 2004
Definition- (YPM 1734 <- Ichthyornis dispar, Struthio camelus, Tetrao major, Vultur gryphus) (new)
Other definitions- (YPM 1451 <- Ichthyornis dispar, Struthio camelus, Tetrao major, Vultur gryphus) (modified from Clarke, 2004)
= "Iaceornis" Clarke, 2002
Comments- Clarke (2004) accidentally defined Iaceornis identically to Apatornis, so I have provided the definition that was intended as a substitute until a formal correction is published.
References- Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.
Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural History. 286: 1-179.
I. marshi Clarke, 2004
Definition- (the species that includes YPM 1734) (Clarke, 2004)
= "Iaceornis marshi" Clarke, 2002
Early Campanian, Late Cretaceous
Hesperornis Zone of the Smoky Hill Chalk Member of the Niobrara Formation, Kansas, US

Holotype- (YPM 1734) dorsal rib, scapulae (52.5 mm), coracoids (24 mm), partial furcula, incomplete sternum, proximal radius, radiale, ulnare, carpometacarpus (36 mm), phalanx II-1 (14 mm), phalanx II-2 (13 mm), ilium (50 mm; lost), pubis (32 mm; lost), ischium (lost), partial femur, incomplete tibiotarsus, fibula (28 mm; lost), fragments
Diagnosis- (after Clarke, 2004) hooked acromion (also in Apsaravis and Lithornithidae).
Other diagnoses- Clarke (2004) listed the strongly tapering omal furcular tip as an apomorphy, but this is also present in Archaeorhynchus, Yixianornis, Anseriformes, Mirandornithes, many Charadriiformes, Gaviidae and Procellariimorphae.
Comments- This specimen was discovered in 1877 and originally referred to Apatornis celer by Marsh (1880), though it is not comparable to the Apatornis holotype. Because of its completeness compared to the Apatornis holotype, it has been the basis of most authors' understanding of the genus since then, until Clarke separated it in 2002 (published in 2004) as Iaceornis. The pelvis which has been the most commonly illustrated portion of the specimen was lost prior to 1955. Both Marsh (1880) and Clarke (2004) described numerous features which differ from Ichthyornis, though Marsh and most authors until Clarke (2002, 2004) were wrong in believing the tibiotarsus lacked a supratendinal bridge. Howard (1955) thought YPM 1734 (as Apatornis) was similar to her new taxon Telmabates (described as a phoenicopteriform but now recognized as a presbyornithid anseriform) and might be referrable to Phoenicopteriformes itself, though she felt a more thorough review should take place before any official reclassification. Martin (1987) described cervical and humeral characters of Apatornis, but these elements are not preserved in the holotype or YPM 1734.
Iaceornis an ichthyornithine? Marsh (1880) considered YPM 1734 part of his Odontotormae when he described it, though never explicitly defended the view. It does share a keeled sternum, large wings and a carpometacarpus with Odontotormae as listed on page 187, but most Aves have these characters too. While this has been followed by most authors since, it seems more due to stratigraphy and tradition than actual character support.
Iaceornis an anseriform? Howard (1955) listed several characters she thought were similar in YPM 1734 and the presbyornithid Telmabates (though she viewed the latter as a phoenicopteriform, so viewed the characters as supporting placement of YPM 1734 in that order). The crossed coracoid sulci on the sternum are similar to not only Phoenicopterus and Telmabates, but also Ichthyornis, casuariids, Phaethon, Leptosomus, Steatornis, ciconiiforms, accipitrids and several other neoavians. The broadly rounded anterior sternal edge is plesiomorphic for ornithuromorphs. The short shaft and flaring sternal end of the coracoid were said to be similar to Telmabates, Phoenicopterus and the basal phoenicopteriform Paloelodus, but these are plesiomorphies which are also seen in such taxa as Gansus, Ichthyornis and Lithornis. The scapular facet of the coracoid being both round and deep was said to be most similar to Telmabates, and while similarly round facets are present in many ornithuromorphs and some look comparatively deep in figures (e.g. Cimolopteryx rara, Palintropus), the distribution of these features over Aves has yet to be studied. The supracoracoid foramen is in a similar position not only to Telmabates, but also to taxa such as Lithornis, Ichthyornis and Yixianornis. The scapula was merely said to resemble Telmabates, which is too vague for comment. A well developed ulnar facet on the proximal radius is also present in Limenavis and Eonessa in addition to Telmabates. The greatly expanded dorsal trochlea on the carpometacarpus is also present in the pangalliform Paraortygoides, Limenavis, Apsaravis and Yixianornis in addition to Telmabates. The carpal trochlea which extends distally to metacarpal III is indeed similar to Telmabates and the presbyornithid Teviornis and not seen in other Mesozoic ornithuromorphs. However, lithornithids and Paraortygoides share this feature as well. The extensor process of metacarpal I is fairly similar to Telmabates and Teviornis in being more elongate than any non-avian taxon and having a generalized triangular shape with proximally placed apex (as in Ichthyornis and Limenavis, though theirs are less elongate), but the lithornithid Pseudocrypturus shares this. According to Howard, in both YPM 1734 and Telmabates, the internal edge of metacarpal III is placed ventral to the ventral crest of the carpal trochlea, but this seems to be true in Apsaravis, Ichthyornis and Limenavis as well as in Teviornis. A trochanteric crest which extends proximal to the ilial facet on the femur is unlike other Mesozoic birds, but is seen in many Aves such as Paraortygoides, Pheonicopterus and the lithornithid Paracathartes.
Hope (2002) suggested the "short, angular" coracoid glenoid was similar to some anseriforms and other Aves, but indeed even Ichthyornis' could be described this way. The long, pointed acromion was said to be similar to anatoids, but is also seen in Ambiortus and Yixianornis. Hope also cited the laterally protruding distal end of the scapular glenoid "with surrounding shelf tapered distally" as a feature shared specifically with presbyornithids, though these are difficult to evaluate in most Mesozoic ornithuromorphs based on the literature alone. The ventromedial edge of the acrocoracoid process is raised as a lip which expands anteriorly in Iaceornis and Anatoidea, but this seems true of Apsaravis and Ichthyornis too. Finally, Hope states that Iaceornis' scapula is more similar to Presbyornis than Juncitarsus (a probable stem mirandornithine) in having a strongly concave dorsal edge anteriorly, but the edge in Iaceornis is actually convex and thus unlike both.
The evidence for an anseriform affinity seems weak, with only the scapular glenoid morphology described by Hope being potentially synapomorphic.
Iaceornis a non-avian ornithurine sensu Chiappe? Elzanowski (1995) placed YPM 1734 outside Aves based on two characters. The acromion was said to be longer than basal avians, but some (e.g. lithornithids, anatoids, Gallus, pelecanids, Cariama) have elongate acromia as well. The supratendinal bridge was said to be absent on the tibiotarsus, but this was a mistake by Marsh.
Clarke (2002, 2004) found Iaceornis to be outside Aves in her analysis based on four characters. There are no pneumatic foramina between the sternal rib articulations, but this is true of many avians as well, including apterygids, phasianoids, most Natatores, most charadriiforms and columbiforms. Similarly, the non-pneumatic coracoid is present in anatids, presbyornithids, and many pangalliforms including the basal Gallinuloides. Metacarpal III does not extend distally past metacarpal II, but this is also true in many Aves such as Pterocnemia, Telmatornis, Telmabates, Teviornis, Anas, Walbeckornis, Miodytes, Limnofregata, gruiforms and charadriiforms. Finally, the medial tibiotarsal condyle projects further anteriorly than the lateral condyle. This is found in numerous Aves however, including Anas, galliforms, most metavians, most Natatores, some charadriiforms and many others.
Despite being the conclusion of the only phylogenetic analysis to include Iaceornis, there is no unambiguous evidence the taxon is outside Aves. This is due in part to the huge variation in the clade, which was only represented in Clarke's matrix by two palaeognaths and four galloanserines. While it might be argued any character diagnosing Aves would be expected to reverse in some example, the preliminary comparisons above suggest some groups contain taxa which match all of Iaceornis' supposedly non-avian characters (e.g. anseriforms, galliforms).
Iaceornis closer to Aves than Ichthyornis? While Howard (1955) implicitly proposed this possibility when allying YPM 1734 with phoenicopteriforms, Clarke (2002, 2004) was the first to support it with characters found in basal avians. Paired intermuscular lines on the sternum and an intermetacarpal space ending distal to metacarpal I are also present in Gansus, which has always been resolved as basal to Ichthyornis in published analyses. The larger extensor process on metacarpal I and supratendinal bridge on the tibiotarsus are valid characters shared with neognaths and tinamids. Notably, lithornithids and ratites can lack all of these characters.
Hope (2002) noted the scapular facet on the coracoid was distal to the glenoid, unlike Ichthyornis. However, this also appears to be the case in Apsaravis and Yixianornis. Hope also stated the scapular glenoid was small and located anterolaterally, but the condition appears similar in Yixianornis. The scapular glenoid being much smaller than the coracoid glenoid does seem to be absent in non-avian ornithuromorphs where both can be observed though (Patagopteryx, Yixianornis, Ichthyornis), but is present in Tinamidae and Neognathae. Hope suggested the prominent acrocoracoid process was consistant with referral to Neognathae, but Gansus and Pseudocrypturus have similarly large processes.
While some of Clarke's and Hope's characters uniting Iaceornis with Aves have been found to be diagnostic of more inclusive clades thanks to recent discoveries (Gansus, Yixianornis, Apsaravis), the small scapular glenoid compared to the coracoid glenoid, large extensor process and supratendinal bridge do support this arrangement. Additionally, the well developed ulnar facet on the proximal radius, carpal trochlea which extends distally to metacarpal III, and trochanteric crest which extends proximal to the ilial facet on the femur noted by Howard as similar to Telmabates are only found in Aves (or in one case in Limenavis too, which is also closer to Aves than Ichthyornis) as well. Thus a placement closer to Aves than to Ichthyornis seems probable, while more exact affinities must await adding Iaceornis to a large matrix of avians. A relationship with galloanserines does seem plausible however, given the preliminary findings here.
References- Marsh, 1880. Odontornithes: a monograph on the extinct toothed birds of North America. United States Geological Exploration of the 40th Parallel. Washington, DC: U.S. Government Printing Office. 201 pp.
Howard, 1955. A new wading bird from the Eocene of Patagonia. American Museum Novitates. 1710, 25 pp.
Martin, 1987. The beginning of the modern avian radiation. Documents des Laboratoires de Geologie de la Faculte des Sciences de Lyon. 99, 9-20.
Elzanowski, 1995. Cretaceous birds and avian phylogeny. Courier Forschungsinstitut Senckenberg. 181, 37-53.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural History. 286: 1-179.

Laornithoidea Cracraft, 1973
Laornithidae Cracraft, 1973
Comments-
Cracraft (1973) created this monotypic family and superfamily for Laornis in his study of Grues, believing it to be related to rallids.
Reference- Cracraft, 1973. Systematics and evolution of the Gruiformes (class Aves). 3, Phylogeny of the suborder Grues. Bulletin of the American Museum of Natural History. 151, 128 pp.
Laornis Marsh, 1870
L. edvardsianus Marsh, 1870
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US

Holotype- (YPM 820) distal tibiotarsus (22.6 mm wide)
Comments- Marsh (1870) felt Laornis showed strong resemblences to anseriforms, procellariiforms and larines. Shufeldt (1915) believed it was a generalized wader, comparing it to turkeys, swans and cranes. Cracraft (1973) redescribed it and assigned it to the Ralli in Gruiformes. Olson (1974) assigned it to Lari, but Olson and Parris (1987) later placed it in the invalid charadriiform family Graculavidae. They felt it was quite similar to Presbyornis, but resembled Palaeotringa in having a large M. peroneus brevis foramen in the anterolateral tibiotarsus. Brodkorb (1978) tentatively suggested affinities to Pelecaniformes.
References- Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary Formations of the United States. American Journal of Science, Series 2. 49, 205-217.
Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences. 19, 1-110.
Cracraft, 1973. Systematics and evolution of the Gruiformes (class Aves). 3, Phylogeny of the suborder Grues. Bulletin of the American Museum of Natural History. 151, 128 pp.
Olson, 1974. Joel Cracraft. Systematics and evolution of the Gruiformes (Class Aves), 3: Phylogeny of the suborder Grues. Auk. 91(4), 862-865.
Brodkorb, 1978. Catalogue of Fossil Birds, Part 5 (Passeriformes). Bulletin of the Florida State Museum, Biological Sciences. 23(3), 140-228.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.

Palaeotringinae Wetmore, 1940
Reference- Wetmore, 1940. A systematic classification for the birds of the world. Smithsonian Miscellaneous Collections. 99(7), 1-11.
Palaeotringa Marsh, 1870
Comments- Marsh (1870) placed this genus in the Grallae. Previously assigned to the Gruiformes, then assigned to the invalid family Graculavidae by Olson and Parris (1987).
References- Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary Formations of the United States. American Journal of Science, Series 2. 49, 205-217.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
P. littoralis Marsh, 1870
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US

Holotype- (YPM 830) distal tibiotarsus
Referred- ?(NJSM 11303) distal humerus (Olson and Parris, 1987)
References- Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary Formations of the United States. American Journal of Science, Series 2. 49, 205-217.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
P. vagans Marsh, 1872
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US

Holotype- (YPM 835) distal tibiotarsus
References- Marsh, 1872. Preliminary description of Hesperornis regalis with notices of four other new species of Cretaceous birds. American Journal of Science, Series 3. 3, 360-365.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.

“Palaeotringa” vetus Marsh 1870
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
basal Hornerstown Formation, New Jersey

Holotype- (ANSP 13361) distal tibiotarsus
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Referred- (AMNH 25221) distal tibiotarsus (Hope, 2002)
Comments- Morton (1834) referred the holotype to Scolopax, though it was later named by Marsh (1870) and placed tentatively in his new genus Palaeotringa. Olson and Parris (1987) removed this from Palaeotringa and synonymized it with Telmatornis priscus, but Hope (2002) noted it differs from charadriiforms in several characters. She found gruids were most similar, along with idiornithids and Telmabates (a presbyornithid). A partial tibiotarsus (YPM 2808) was referred to P. vetus by Halsey (1955), but as this is from the Eocene, it is unlikely to belong to this species.
References- Morton, 1934. Synopsis of the Organic Remains of the Cretaceous of the US. Philadelphia: Key and Biddle. 96 pp.
Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary Formations of the United States. American Journal of Science, Series 2. 49, 205-217.
Halsey, 1955. A check-list of the Cretaceous and Tertiary vertebrates of New Jersey. Journal of Paleontology. 29, 903-914.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Volgavis Nessov and Jarkov, 1989
V. marina Nessov and Jarkov, 1989
Late Maastrichtian, Late Cretaceous
Malaja Ivanovka, Russia
Holotype
- (ZIN PO 3638) incomplete mandibles
Comments- Considered a possible charadriiform by Nessov and Jarkov (1989) and Hope (2002), the latter noted the decurved symphysis resembles fregatids and stercorariids. Such a feature is probably prone to convergence among seabirds, thus Volgavis' relationships remain uncertain.
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.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

unnamed avian (Brodkorb, 1963)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Material- (ACM 12359) proximal coracoid (Longrich et al., 2011)
(UCMP 53957) proximal coracoid (Brodkorb, 1963)
Diagnosis- (after Longrich et al., 2011) paddle-shaped glenoid; massive medial edge to the glenoid; large scapular facet; large scapular facet that is wider mediolaterally than long anteroposteriorly.
Comments- UCMP 53957 was a paratype of Cimolopteryx maxima (Brodkorb, 1963), which was followed by Hope (2002). It was reassigned to Lancian Ornithurine F by Longrich et al. (2011).
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19,55-70.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

Aves indet. (Kurochkin, 1988)
Late Campanian, Late Cretaceous
Baruungoyot Formation, Mongolia
Material
- tarsometatarsus (40.3 mm)
Comments- Referred to the Presbyornithidae by Kurochkin (1988, 2000), but said to be undiagnostic past Aves by Kurochkin et al. (2002).
References- Kurochkin, 1988. [Cretaceous birds of Mongolia and their significance for study of the phylogeny of class Aves.] Trudy Sovmestnoi Sovetsko-Mongol’skoi Paleontologicheskoi Ekspeditsii. 34, 33-42.
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. Cambridge University Press. 544-559.
Kurochkin, Dyke and Karhu, 2002. A new presbyornithid bird (Aves, Anseriformes) from the Late Cretaceous of southern Mongolia. American Museum Novitates. 3386, 1-11.

unnamed avian (Tokaryk and James, 1989)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Material
- (AMNH coll.) proximal coracoid (Longrich et al., 2011)
(UCMP 53962) proximal coracoid (Longrich, 2009)
(UCMP 53963) proximal coracoid (Longrich, 2009)
Late Maastrichtian, Late Cretaceous
Frenchman Formation, Saskatchewan, Canada;

(SMNH P1927.936) proximal coracoid (Tokaryk and James, 1989)
Comments- Longrich (2009) states these specimens are not referrable to Cimolopteryx rara (citing personal observation) and refers to them as "Cimolopteryx" n. sp.. Longrich et al. (2011) later determined the material does not share apomorphies with Cimolopteryx, though its position in Aves remains uncertain. They term it Lancian Ornithurine A.
References- Brodkorb, 1963.
Tokaryk and James, 1989. Cimolopteryx sp. (Aves, Charadriiformes) from the Frenchman Formation (Maastrichtian), Saskatchewan. Canadian Journal of Earth Sciences. 26, 2729- 2730.
Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30(1), 161-177.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

unnamed Aves (Elzanowski and Brett-Surman, 1995)
Late Maastrichtias, Late Cretaceous
Hell Creek Formation, Montana, US
Material
- (UCMP 117598) premaxilla
(UCMP 117599) distal tarsometatarsus
Comments- Elzanowski and Brett-Surman (1995) thought the premaxilla resembled most scolopacids and Nycticryphes in having a median ventral groove extending to the anterior tip, but was unlike these taxa in being prokinetic. The tarsometatarsus was noted to be similar to anseriforms in the distally placed vascular foramen (ventrally), with anatids in the compact trochlea, and with Presbyornis in the large distal vascular foramen. However, other characters are more similar to Chionis and gruoids. Stidham (2001) considered it more likely related to stem-mirandornithine Junctitarsus without comment.
Reference- Elzanowski and Brett-Surman, 1995. Avian premaxilla and tarsometatarsus from the Uppermost Cretaceous of Montana. Auk. 112, 762-766.
Stidham, 2001. The origin and ecological diversification of modern birds: Evidence from the extinct wading ducks, Presbyornithidae (Neornithes: Anseriformes). PhD Thesis, University of California. 257 pp.

unnamed avian (Kakegawa, 1998)
Campanian, Late Cretaceous
Orannai Formation, Japan

Material- (NSMJ coll.) sacrum, scapula, pelvis, fibula, pedal phalanx
References- Kakegawa, 1998. The Late Cretaceous Aves from Wakkanai, Hokkaido. (Kagawa University, March 1998). Master's Thesis.
Kakegawa, 1998. A Late Cretaceous aquatic bird from Hokkaido Japan. SVPCA.

undescribed avian (Hope, 2002)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Material- (UCMP 53960) two cervical vertebral fragments
Comments- Questionably referred to Torotix by Brodkorb in the UCMP catalog.
Reference- Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

unnamed probable avian (Agnolin and Martinelli, 2009)
Campanian-Maastrichtian, Late Cretaceous
Los Alamitos Formation, Rio Negro, Argentina
Material
- (MACN PV RN 1115) distal tarsometatarsus
Reference- Agnolin and Martinelli, 2009. Fossil birds from the Late Cretaceous Los Alamitos Formation, Río Negro province, Argentina. Journal of South American Earth Sciences. 27, 42-49.

undescribed Aves (Rejcek, 2011)
Early Maastrichtian, Late Cretaceous
Cape Lamb Member of the Snow Hill Island Formation, Vega Island, Antarctica
Material
- at least one partial skeleton, twenty elements
Comments- To be described by Lamanna, Clarke, Sertich, MacPhee, et al..
Reference- Rejcek, 2011. Big haul: Paleontologists return from Antarctic expedition with about 200 fossils. The Antarctic Sun. 11-16-2011.

Palaeognathae Pycraft, 1900
Definition- crown (Struthio camelus + Tinamus major) (Gauthier and de Queiroz, 2001)

Limenavis Clarke and Chiappe, 2001
L. patagonica Clarke and Chiappe, 2001
Campanian-Maastrichtian, Late Cretaceous
Allen Formation, Rio Negro, Argentina
Holotype
- (PVL 4731) distal humerus, proximal radius, proximal and distal ulna, radiale, partial ulnare, proximal and distal carpometacarpus, incomplete phalanx II-1, fragments
Diagnosis- (after Clarke and Chiappe, 2001) three fossae on the proximal surface of the dorsal supracondylar process of the humerus (also in Ichthyornis, Lithornis and Torotix); attachment of the pars ulnaris of the trochlea humeroulnaris on the proximal ulna developed as a pit-shaped fossa; scar of the ligamentum collaterale ventrale of the ulna proximodistally elongate, extending down the caudal margin of the brachial impression (also in Podiceps, Gavia, Balaeniceps, Grus, Numenius and Burhinus); deep infratrochlear fossa proximal to pisiform process on carpometacarpus (also in Ichthyornis, Lithornis, Podiceps, some procelariiforms, Rallus and cuculiforms); pisiform process with its proximal surface at approximately the same level as the proximal surface of metacarpal I.
Other diagnoses- Clarke and Chiappe (2001) also included the deep tendinal groove of the ulnare in their diagnosis, but this is present in most Aves except ratites, Chauna, possibly galliforms, and some diving taxa.
Comments- The holotype was discovered in the mid 1980's but only described in 2001 by Clarke and Chiappe. Those authors used a matrix consisting mostly of forelimb characters to place Limenavis as a carinate more derived than Ichthyornis, but less so than Lithornis and Aves. Clarke (2002) scored Limenavis in her large cladistic analysis and found it to be a carinate more derived than Ichthyornis, but less than Iaceornis and Aves (including Lithornis), agreeing with the results of the earlier study.
Limenavis a carinate? Clarke and Chiappe (2001) placed Limenavis closer to Aves than Ichthyornis based on two characters. The articular surface of the dorsal ulnar condyle is proximally truncated and the carpal tubercle of the ulna is absent. Neither are known for non-carinates, and at least the latter is also untrue in Apsaravis, though each does exhibit some variation within Aves.
Clarke (2002) placed Limenavis closer to Aves than Ichthyornis because its metacarpal I extensor process is supposedly more projected, but this seems to be untrue. The projection perpendicular to the carpometacarpus shaft from the medial concavity in metacarpal I (compared to the width from the medial condyle of metacarpal I to the lateral carpometacarpal edge) is 18% in Ichthyornis and 16% in Limenavis. Limenavis' is more robust and more highly angled anteriorly, but the distribution of these attributes is as of yet unstudied.
Thus one character places Limenavis in Carinatae and another places it closer to Aves than Apsaravis.
Limenavis outside Aves? Only one character in Clarke and Chiappe's (2001) study supports its exclusion from Lithornis+Aves - metacarpal III ends proximal to metacarpal II. This is also found in anseriforms, stem galliforms, Phaethon, Mesitornis, Pterocles, gaviids, procelariiforms, steganopodes and charadriiforms. Four additional characters support placing Limenavis and Lithornis outside Aves, but as other analyses are consistant in placing Lithornis within Aves, these could equally well support placing Limenavis in Lithornithidae. Of these characters, the loss of two small fossae on the dorsal supracondylar tubercle of the distal humerus and loss of a deeply excavated infratrochlear fossa of the carpometacarpus are forelimb simplifications that may have been lost in crown paleognaths simply due to their reduced wings. The third character (lateral margin of manual phalanx II-1 straight) is also found in Neoaves in their matrix, making the strongly convex margin equally likely to have converged in crown palaeognaths and galloanserines as opposed to being basal for Aves. The last character (interosseal groove absent on distal carpometacarpus) is distributed sporadically throughout Aves, being present in Gallus, Anas and charadriiforms in their matrix for instance.
Clarke (2002) only used one different character to exclude Limenavis from Aves + Iaceornis (here viewed as an avian)- the less projected extensor process on metacarpal I. However, they note that various neoavians have equally low processes, and palaeognaths including lithornithids do as well.
In conclusion, all of the proposed characters to exclude Limenavis from Aves are widespread in that clade, with five of the six being present in Lithornis. It may most parsimoniously be a lithornithid, though any firm conclusions on its affinities await a more detailed comparison to basal avians.
References- Clarke and Chiappe, 2001. A new carinate bird from the Late Cretaceous of Patagonia (Argentina). American Museum Novitates. 3323, 1-23.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.

Neognathae Pycraft, 1900
Definition- crown (Pluvialis apricaria <- Struthio camelus, Tinamus major) (Gauthier and de Queiroz, 2001)

Novacaesareala Parris and Hope, 2002
N. hungerfordi Parris and Hope, 2002
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US

Holotype- (NJSM 11302) distal humerus, proximal radius, partial ulna, fragments
Diagnosis- (modified from Parris and Hope, 2002) humeral shaft slightly flattened craniocaudally; brachial fossa distinctly tripartite, divided by pronounced crests into the more proximal brachial fossa proper and a ventral and dorsal supracondylar fossa; brachial fossa proper divided into a shallow proximal shelf and much deeper dorsal pit; broad flexor process.
Comments- Olson and Parris (1987) tentatively assigned this specimen to Graculavidae. Parris and Hope (2002) note it closely resembles Torotix except for the broad flexor process, presbyornithids except for the narrow ventral brachial depression rim, pelecaniforms except for the unflared ventral epicondyle and flexor process, and both presbyornithids and pelecaniforms except for the craniocaudally flattened shaft (unreported in Torotix) and the more distally extended brachial fossa. Given that information, and the assignment of Torotix to Pelecaniformes or Presbyornithidae by different authors, it seems possible Novacaesareala could be referred to either clade. Most recently, Mayr and Scofield (2015) compared it favorably to the Paleocene phaethontiform Zhylgaia in the very short flexor process, elongate ventral supracondylar tubercle and marked brachial fossa.
Although Ford emmends the species name to hungerfordorum because it was named after multiple people, such emmendations aren't allowed according to the 1999 ICZN.
References- Olson and Parris, 1987. The Cretaceous Birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Parris and Hope, 2002. New interpretations of the birds from the Navesink and Hornerstown Formations, New Jersey, USA (Aves: Neornithes). In Zhou and Zhang (eds.). Proceedings of the 5th Symposium of the Society of Avian Paleontology and Evolution, Beijing, 1-4 June 2000. 113-124.
Mayr and Scofield, 2015. New avian remains from the Paleocene of New Zealand: The first early Cenozoic Phaethontiformes (tropicbirds) from the Southern Hemisphere. Journal of Vertebrate Paleontology. DOI:
10.1080/02724634.2015.1031343

Qinornis Xue, 1995
Q. paleocenica Xue, 1995
Danian-Selandian, Paleocene, Paleogene
Fangou Formation, Shanxi, China
Holotype
- (XD78sh048.3) (adult) tarsometatarsus (42 mm), phalanx II-1 (8.3 mm), phalanx II-2 (6.5 mm), pedal ungual II (2.4 mm), phalanx III-1 (9.3 mm), phalanx III-2 (7 mm), phalanx III-3 (5.8 mm), pedal ungual III (3.3 mm), phalanx IV-1 (6.85 mm), phalanx IV-2 (3.3 mm), phalanx IV-3 (3.5 mm), phalanx IV-4 (3.3 mm), pedal ungual IV (2.85 mm)
Paratypes- ....(XD78sh048.1) distal tibiotarsus
....(XD78sh048.2) incomplete tibiotarsus (~56 mm)
Comments- The type material was discovered in 1977-78 and described by Xue in 1995 as incertae sedis within birds. Xue considered the solid tarsometatarsus, incomplete tarsometatarsal fusion and open distal vascular foramen indicated the taxon either more basal than Aves or a subadult perhaps related to Charadriiformes or Gruiformes. Mayr (2007) thought the material was adult due to the fused distal tarsals and well defined distal articular surfaces, so considered it a possibly non-avian ornithuromorph based on the incomplete tarsometatarsal fusion. This would be the first bird outside the crown group Aves to be recognized in the Tertiary, which is why it is included in this otherwise Mesozoic theropod website. However, it ends up in Neognathae when included in my modified version of Clarke's analysis.
References- Xue, 1995. Qinornis paleocenica - a Paleocene bird discovered in China. Courier Forschungsinstitut Senckenberg. 181, 89-93.
Mayr, 2007. The birds from the Paleocene fissure filling of Walbeck (Germany). Journal of Vertebrate Paleontology. 27(2), 394-408.

Torotigidae Brodkorb, 1963
Torotix Brodkorb, 1963
T. clemensi Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Holotype- (UCMP 53958) distal humerus
Diagnosis- (after Parris and Hope, 2002) differs from Novacaesareala in having a narrow flexor process.
Comments- Assigned to Phoenicopteriformes by Brodkorb (1963), it was later placed in Charadriiformes (Olson and Feduccia, 1980; Olson, 1985), and most recently to Pelecaniformes by Hope (2002). The latter was based on several characters- ventral rim of brachial fossa very narrow; attachment for ventral collateral ligament small; flexor process broad and very short; sites for M. flexor carpi ulnaris and pronator profundus oriented ventrally; ventral epicondyle extended only slightly ventrally. However, Parris and Hope (2002) state the flexor process is narrow, unlike pelecaniforms and Novacaesareala. Stidham (2001) stated most features fell within the range of Presbyornis and even posited synonymy of the genera, though he noted the brachial fossa is deeper than P. pervetus and the anterior articular ligament attachment faces more distally.
Hope (2002) notes Brodkorb questionably referred two cervical vertebral fragments to Torotix (see entry under undescribed avian).
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. in Sibley (ed.). Proceedings of the XIII International Ornithological Congress. 50-70.
Olson and Feduccia, 1980. Presbyornis and the origin of the Anseriformes (Aves, Charadrimorphae). Smithsonian Contribs. Zool. 323, 24 pp.
Olson, 1985. The fossil record of birds. 79-239. in Farner, King and Parkes (eds.). Avian Biology. vol VIII. Academic Press, New York.
Stidham, 2001. The origin and ecological diversification of modern birds: Evidence from the extinct wading ducks, Presbyornithidae (Neornithes: Anseriformes). PhD Thesis, University of California. 257 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Parris and Hope, 2002. New interpretations of the birds from the Navesink and Hornerstown Formations, New Jersey, USA (Aves: Neornithes). In Zhou and Zhang (eds.). Proceedings of the 5th Symposium of the Society of Avian Paleontology and Evolution, Beijing, 1-4 June 2000. 113-124.

undescribed neognath (Hilton, Gohre, Embree and Stidham, 1999)
Campanian, Late Cretaceous
Chico Formation, California, US
Material
- (UCMP 171185) ulna
Reference- Hilton, Gohre, Embree and Stidham, 1999. California's first fossil evidence of Cretaceous winged vertebrates. California Geology. 52(4), 4-10.

Galloanserae Sibley et al., 1988
Definition- crown (Gallus gallus + Anser anser) (Gauthier and de Queiroz, 2001)
= Galloanseres Weber, 1993

Pangalliformes Clarke, 2004
Definition- (Gallus gallus <- Anser anser) (Clarke, 2004)
Diagnosis- (after Clarke, 2004) asymmetrical development of the edges of the trochlea of metatarsal III.
References- Clarke, 2004. Morphology, phylogenetic taxonomy, and systematics of Ichthyornis and Apatornis (Avialae: Ornithurae). Bulletin of the American Museum of Natural History. 286, 1-179.

Austinornis Clarke, 2004
Definition- (Austinornis lentus <- Gallus gallus, Crax rubra, Megapodius freycinet) (Clarke, 2004)
= "Austinornis" Clarke, 2002
A. lentus (Marsh, 1877) Clarke, 2004
Definition- (the species that includes YPM 1796)
= Graculavus lentus Marsh, 1877
= Ichthyornis lentus (Marsh, 1877) Marsh, 1880
= "Austinornis" lentus (Marsh, 1877) Clarke, 2002
Late Cretaceous
Austin Chalk, Texas, US

Holotype- (YPM 1796) distal tarsometatarsus
References- Marsh, 1877. New fossil vertebrates. American Journal of Science. 14, 249-256.
Marsh, 1880. Odontornithes: a monograph on the extinct toothed birds of North America. United States Geological Exploration of the 40th Parallel. Washington, DC: U.S. Government Printing Office. 201 pp.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.
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 possible pangalliform (Agnolin, Novas and Lio, 2006)
Late Turonian-Coniacian, Late Cretaceous
Portezuelo Member of Rio Neuquen Formation, Neuquen, Argentina
Material
- (PVPH 237) proximal coracoid (~30 mm)
Comments- Agnolin et al. (2006) noted this was similar to galliforms in having a distinct scar for the insertion of the M. acrocoracohumeralis and a reduced procoracoid process. Within Galliformes, it was stated to resemble Quercymegapodiidae, Gallinuloididae, Paraortygidae and Megapodiidae in having a laterally expanded humeral articular surface and an ovoid and concave scapular cotyle.
Reference- Agnolin, Novas and Lio, 2006. Neornithine bird coracoid from the Upper Cretaceous of Patagonia. Ameghiniana. 43(1), 245-248.

Anseriformes Wagler, 1830
Definition- crown (Anser anser <- Gallus gallus, Passer domesticus) (Martyniuk, 2012)

undescribed possible anseriform (Hope, 2002)
Late Campanian, Late Cretaceous
Judith River Group, Alberta, Canada
Material
- (RTMP 93.19.1) proximal coracoid
Reference- Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.

Anseres Linnaeus, 1758

Anatalavis Olson and Parris, 1987
A. rex (Shufeldt, 1915) Olsen and Parris, 1987
= Telmatornis rex Shufeldt, 1915
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US
Holotype
- (YPM 902) incomplete humerus (~73 mm)
Paratype- (YPM 948) incomplete humerus (~76 mm)
References- Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences. 19, 1-110.
Cracraft, 1972. A new Cretaceous charadriiform family. Auk. 89, 36-46.
Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Olson, 1999. The anseriform relationships of Anatalavis Olson and Parris (Anseranatidae), with a new species from the Lower Eocene London Clay. Smithsonian Contributions to Paleobiology. 89, 231-243.

Anatoidea Leach, 1820
Definition- (Anas platyrhynchos <- Anseranas semipalmata) (suggested)
Other definitions- (Anser anser <- Anseranas semipalmata) (Martyniuk, 2012)

Vegavis Clarke, Tambussi, Noriega, Erickson and Ketcham, 2005a
V. iaai Clarke, Tambussi, Noriega, Erickson and Ketcham, 2005a
Late Maastrictian, Late Cretaceous
Lower Sandwich Bluff Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Holotype- (MLP 93-I-3-1) two cervical vertebrae, five dorsal vertebrae, over six dorsal ribs, synsacrum (85 mm), scapula, coracoid (35.6 mm), humeri (one proximal; 124 mm), distal radius, ulna, pelvis, femora (~50 mm), tibiotarsus (124 mm), fibulae, partial tarsometatarsi
Diagnosis- (from Clarke et al., 2005) low ridge on the medial edge of the proximal tibiotarsus.
Comments- This specimen was discovered in 1992 and originally assigned to Presbyornithidae by Noriega and Tambussi (1995) and Hope (2002), before being redescribed and named as a new taxon of anatoid by Clarke et al. (2005a).
References- Noriega and Tambussi, 1995. A Late Cretaceous Presbyornithidae (Aves: Anseriformes) from Vega Island, Antarctic Peninsula: Paleobiogeographic implications. Ameghiniana. 32, 57-61.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Clarke, Tambussi, Noriega, Erickson and Ketcham, 2005a. Definitive fossil evidence for the extant avian radiation in the Cretaceous. Nature. 433, 305-308.
Clarke, Tambussi, Noriega, Erickson and Ketcham, 2005b. New Cretaceous fossil evidence for the timing and pattern of avian diversification. Journal of Vertebrate Paleontology. 25(3), 46A.

Presbyornithidae Wetmore, 1926

Teviornis Kurochkin, Dyke and Karhu, 2002
T. gobiensis Kurochkin, Dyke and Karhu, 2002
Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia
Holotype
- (PIN 4499-1) distal humerus, radiale, ulnare, carpometacarpus (65 mm), phalanx II-1 (30.8 mm), phalanx III-1 (13.9 mm)
Diagnosis- (after Kurochkin et al., 2002) dorsal supracondylar tuber of humerus extended far proximally; distal articular facet of metacarpal II widened distally; ventral portion of metacarpal II distal articular facet elevated in the direction of the tubercle for the insertion of m. abductor digiti majoris; distal articular facet of metacarpal III divided by a craniocaudal groove into two distinct facets.
Other diagnoses- De Pietri et al. (2016) found that one character used bu Kurochkin et al. (2002) in their diagnosis (infratrochlear fossa of carpometacarpus stretched markedly craniocaudally) is also present in the presbyornithid Wilaru. They similarly noted another proposed character (proximal portion metacarpal III widened both dorsoventrally and craniocaudally with respect to its distal portion) is present in anhimids and other anseriforms, so may be a symplesiomorphy compared to Presbyornis.
Comments- Discovered in 1987, but not described until Kurochkin et al. (2002). While Clarke and Norell (2004) questioned the presbyornithid and anseriform identity of Teviornis based on broader distributions of the characters proposed by Kurochkin et al., De Pietri et al. (2016) described additional characters which in combination are only known in presbyornithids.
References- Kurochkin, Dyke and Karhu, 2002. A new presbyornithid bird (Aves, Anseriformes) from the Late Cretaceous of Southern Mongolia. American Museum Novitates. 3386, 11 pp.
Clarke and Norell, 2004. New avialan remains and a review of the known avifauna from the Late Cretaceous Nemegt Formation of Mongolia. American Museum Novitates. 3447, 12 pp.
De Pietri, Scofield, Zelenkov, Boles and Worthy, 2016. The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: The youngest record of Presbyornithidae. Royal Society Open Science. 3, 150635.

undescribed presbyornithid (Hope, 2002)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, US
Material
- (ANSP 15866) coracoid
References- Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Stidham, 2009. Latest Cretaceous presbyornithids (Anseriformes) from North America. Journal of Vertebrate Paleontology. 29(3), 186A.

Presbyornithidae indet. (Hope, 2002)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Material
- (AMNH 21929) partial scapula
(AMNH 22602) anterior sternum
(AMNH 22603) proximal scapula
(YPM 868) proximal scapula
References- Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Stidham, 2009. Latest Cretaceous presbyornithids (Anseriformes) from North America. Journal of Vertebrate Paleontology. 29(3), 186A.

Presbyornithidae gen et sp. nov. (Stidham, 2001)
Late Maastrichtian-Early Danian, Late Cretaceous-Paleocene
Hell Creek Formation, Montana, US

Material- (RAM 6707; intended holotype) incomplete coracoid
(RAM 6708) anterior sternum
(UCMP 130710) proximal scapula
(UCMP 130711) proximal scapula
(UCMP 175251) proximal coracoid
(UCMP 187208) proximal coracoid
Early Danian, Paleocene
Fort Union Formation, Montana, US

(UCMP 130713) proximal coracoid
Comments- Stidham (2001) describes this material in his thesis as a new genus and species of presbyornithid. As the taxon name is otherwise unpublished, it is not listed here.
References- Stidham, 2001. The origin and ecological diversification of modern birds: Evidence from the extinct wading ducks, Presbyornithidae (Neornithes: Anseriformes). PhD Thesis, University of California. 257 pp.
Stidham, 2009. Latest Cretaceous presbyornithids (Anseriformes) from North America. Journal of Vertebrate Paleontology. 29(3), 186A.
Presbyornithidae gen nov. sp. (Brodkorb, 1963)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Material- (UCMP 53964) distal carpometacarpus (Brodkorb, 1963)
(UCMP 187210) proximal scapula (Stidham, 2001)
(UCMP 187211) (juvenile) proximal scapula (Stidham, 2001)
Early Danian, Paleocene
Hell Creek Formation, Montana, US

(AMNH 24322) anterior sternum (Stidham, 2001)
(UCMP 187209) proximal scapula (Stidham, 2001)
Comments- Brodkorb (1963) referred distal carpometacarpus UCMP 53964 to Cimolopteryx rara, but it was later reassigned by Stidham (2001) to an unnamed species of his new presbyornithid genus. The species differs from the intended type species in being much smaller, but was left unnamed by Stidham due to the lack of preserved coracoids.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Stidham, 2001. The origin and ecological diversification of modern birds: Evidence from the extinct wading ducks, Presbyornithidae (Neornithes: Anseriformes). PhD Thesis, University of California. 257 pp.
Stidham, 2009. Latest Cretaceous presbyornithids (Anseriformes) from North America. Journal of Vertebrate Paleontology. 29(3), 186A.

Neoaves Sibley et al., 1988
Definition- (Passer domesticus <- Anas platyrhynchos) (modified from Sereno, 1998)
Other definitions- crown (Passer domesticus <- Gallus gallus, Anser anser) (Gauthier and de Queiroz, 2001)
= Coronaves Fain and Houde, 2004
= Metaves Fain and Houde, 2004
= Insolitaves Yuri, Kimball, Harshman, Bowie, Braun, Chojnowski, Han, Hackett, Huddleson, Moore, Reddy, Sheldon, Steadman, Witt and Braun, 2013
= Litoritelluraves Yuri, Kimball, Harshman, Bowie, Braun, Chojnowski, Han, Hackett, Huddleson, Moore, Reddy, Sheldon, Steadman, Witt and Braun, 2013
= Columbea Jarvis et al., 2014
= Cursorimorphae Jarvis et al., 2014
= Passerea Jarvis et al., 2014

unnamed neoavian (Brodkorb, 1963)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Material
- (UCMP 53969) quadrate
Comments- Brodkorb (1963) referred this to Cimolopteryx rara within Charadriiformes, but Hope (2002) noted it was not a charadriiform. The separated otic head is a character of neoavians and a few other taxa (Shuvuuia, Confuciusornis, Enaliornis), but the first two differ in lacking a pterygoid condyle. Hope noted Elzanowski et al. are working on the specimen.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. in Sibley (ed.). Proceedings of the XIII International Ornithological Congress. 50-70.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Aequorlitornithes Prum, Berv, Dornburg, Field, Townsend, Lemmon and Lemmon, 2015

Charadriiformes Huxley, 1867

Cimolopterygidae Brodkorb, 1963
Diagnosis- (after Agnolin, 2010) humeral articular surface strongly oriented ventrally; procoracoid process well extended sternally and developed as thin lamina; large and ventrally located supracoracoid foramen.
Comments- While largely ignored since Brodkorb created it, this family was reinstated by Agnolin (2010) for Cimolopteryx, Ceramornis and Lamarqueavis. As the diagnosis is purely based on coracoid morphology, the inclusion of Graculavus and Telmatornis (both based on humeral material) is unknowable.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

Cimolopteryx Marsh, 1892
= “Cimolopteryx” Marsh, 1889
Diagnosis- (after Hope, 2002) coracoid robust; neck of the coracoid stout and subtriangular in cross section; scapular cotyla of the coracoid slightly elongated transverse to the long axis of the coracoid; lateral process of the coracoid small.
References- Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K–Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.
C. rara Marsh, 1892
= “Cimolopteryx rara” Marsh, 1889
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Holotype- (YPM 1805) coracoid
Diagnosis- (after Longrich et al., 2011) slender, dorsoventrally compressed coracoid shaft; weakly triangular scapular cotyle, weak medial excavation of acrocoracoid; prominent buttress inside triosseal canal and below scapular cotyle; coracoid with lateral process.
Comments- Cimolopteryx was first mentioned in a footnote by Marsh (1889) before being officially described in 1892. Brodkorb (1963) referred distal carpometacarpus UCMP 53964 to C. rara, but it was later identified by Stidham (2001) as an unnamed species of his new presbyornithid genus.
References- Marsh, 1889. Discovery of Cretaceous Mammalia. American Journal of Science. 38, 83.
Marsh, 1892. Notes on Mesozoic vertebrate fossils. American Journal of Science. 44, 170-176.
Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Stidham, 2001. The origin and ecological diversification of modern birds: Evidence from the extinct wading ducks, Presbyornithidae (Neornithes: Anseriformes). PhD Thesis, University of California. 257 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30(1), 161-177.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

"Cimolopteryx" maxima Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (UCMP 53973) proximal coracoid
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, US

Referred- ?(ANSP 15867) proximal coracoid (Hope, 2002)
Diagnosis- (after Hope, 2002) twice the size of Cimolopteryx rara; neck of the shaft flatter and broader; the foramen for N. supracoracoideus less recessed from the scapular facet and much less steeply angled in its course than in C. rara.
(after Longrich et al., 2011) ear-shaped glenoid; shallow acrocoracoid fossa; tear-drop shaped scapular facet with straight medial edge; strong caudal extension of the glenoid around the scapular facet.
Comments- The paratype UCMP 53957 was reassigned to Lancian Ornithurine F by Longrich et al. (2011). Longrich et al. (2011) stated "no features were found that support referral of this form to Cimolopteryx and this assignment was not supported by our analysis." It claded in Aves in their phylogenetic analysis based on Clarke's matrix. Agnolin (2010) noted two of their three cimolopterygid characters could not be determined in this species.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

Lamarqueavis Agnolin, 2010
Diagnosis- (after Agnolin, 2010) extended and large procoracoid process; humeral articular surface subrectangular in contour; scapular cotyla transversely elongate with respect to long axis of coracoid.
Reference- Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
L. australis Agnolin, 2010
Maastrichtian, Late Cretaceous
Allen Formation, Rio Negro, Argentina

Holotype- (MML 207) partial coracoid
Diagnosis- (after Agnolin, 2010) large and longitudinally convex procoracoid process; supracoracoid foramen distally located; humeral facet of coracoid strongly tilted medially.
Reference- Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
L. minima (Brodkorb, 1963) Agnolin, 2010
= Cimolopteryx minima Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (UCMP 53976) proximal coracoid
Diagnosis- (after Longrich et al., 2011) broad, dorsoventrally compressed coracoid shaft; strongly triangular scapular cotyle; glenoid deflected away from shaft in dorsal view; lateral edge of glenoid straight in lateral view.
Comments- Longrich et al. (2011) found no characters to support the referral of minima to Cimolopteryx, though it did clade in Aves in their phylogenetic analysis based on Clarke's matrix. Agnolin (2010) later referred it to his new genus Lamarqueavis.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.
L. petra (Hope, 2002) Agnolin, 2010
= Cimolopteryx petra Hope, 2002
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Holotype- (AMNH 21911) proximal coracoid
Diagnosis- (after Longrich et al., 2011) teardrop-shaped scapular cotyle; glenoid that is strongly angled inwards in dorsal view; absence of an acrocoracoid medial fossa.
Comments- Though Longrich (2009) stated Cimolopteryx petra is identical to C. rara except smaller and referred it to that species, he later (Longrich et al., 2011) stated "the differences are too extensive to warrant referral to the same genus and such an assignment is not supported by phylogenetic analysis." It claded in Aves in their phylogenetic analysis based on Clarke's matrix. Agnolin (2010) later referred it to his new genus Lamarqueavis.
References- Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30(1), 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.
L. sp. nov. (Longrich, 2009)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- (UALVP 47943; ornithurine B; Irvine bird) proximal coracoid
?...(UALVP 47944) anterior sternum
?(UALVP coll.) sternal fragment
Diagnosis- (after Longrich, 2009) circular scapular cotyle; large, ventrally placed supracoracoideus nerve foramen; longitudinal ridge on medial surface of coracoid below acrocoracoid process; very small size.
References- Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

Ceramornis Brodkorb, 1963
C. major Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Holotype- (UCMP 53959) proximal coracoid
Diagnosis- (after Longrich et al., 2011) depression on lateral surface of coracoid posteroventral to glenoid; prominent acrocoracoid medial fossa; ovoid glenoid.
Comments- Brodkorb (1963) originally placed this taxon in Cimolopterygidae within Charadriiformes. Hope (2002) notes this taxon shows a few plesiomorphic charadriiform-like characters, but lacks charadriiform synapomorphies. Longrich et al. (2011) included it in a version of Clarke's analysis and found Ceramornis to be in Aves. Agnolin (2010) noted derived characters shared with Cimolopteryx and Lamarqueavis.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. in Sibley (ed.), Proceedings of the 13th International Ornithological Congress. American Ornithologists' Union. pp. 50-70.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

unnamed cimolopterygid (Longrich, 2009)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- (RTMP 86.112.6; ornithurine A) proximal coracoid
Diagnosis- (after Longrich, 2009) large size; humeral articular facet placed anterolaterally with respect to scapular cotyle; shallow scapular cotyle; coracoid shaft massive and posteriorly bowed.
References- Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

unnamed cimolopterygid (Longrich, 2009)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- (UALVP 47942; ornithurine C) proximal coracoid
Diagnosis- (after Longrich, 2009) small size; subcircular scapular cotyle; procoracoid process absent.
References- Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

unnamed cimolopterygid (Longrich, 2009)
Late Campanian, Late Cretaceous
Oldman Formation, Alberta, Canada
Material
- (RTMP 88.87.27; ornithurine D; Devil's Coulee bird) proximal coracoid
Diagnosis- (after Longrich, 2009) robust coracoid neck; robust rim of scapular cotyle; small, proximally placed nerve foramen with a slit-like ventral opening; relatively small size.
References- Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

unnamed cimolopterygid (Longrich, 2009)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- (RTMP 1993.19.1; ornithurine E; Steveville bird) proximal coracoid
Diagnosis- (after Longrich, 2009) scapular cotyle strongly teardrop-shaped; supracoracoideus nerve foramen open.
References- Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

unnamed cimolopterygid (Longrich, 2009)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- (RTMP 1993.116.0001; ornithurine F; Onefour bird) proximal coracoid
Diagnosis- (after Longrich, 2009) subtrapezoidal humeral articular facet; anterior surface of coracoid forms a sharp ridge; scapular cotyle weakly teardrop-shaped; very small size.
Comments- Though Hope (2002) referred this to Cimolopteryx sp., Longrich (2009) found an assignment past Ornithurae sensu Chiappe could not be justified.
References- Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Longrich, 2009. An ornithurine-dominated avifauna from the Belly River Group (Campanian, Upper Cretaceous) of Alberta, Canada. Cretaceous Research. 30, 161-177.
Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

unnamed possible cimolopterygid (Agnolin, 2010)
?Cretaceous
?Argentina
Material
- (MML 208) proximal coracoid
Reference- Agnolin, 2010. An avian coracoid from the Upper Cretaceous of Patagonia, Argentina. Studia Geologica Salmanticensia. 46(2), 99-119.

Graculavidae Furbringer, 1888 sensu Olson, 1985
Graculavinae Furbringer, 1888
References- Furbringer, 1888. Untersuchungen zur Morphologie und Systematik der Vogel, zugleich ein Beitrag zur Anatomie der Stiitz - und Bewegungsorgane. 2 volumes, 1751 pp.
Olson, 1985. The Fossil Record of Birds. in Famer, King and Parkes (eds.). Avian Biology. 8, 79-238.
Graculavus Marsh, 1872
= Limosavis Shufeldt, 1915
Diagnosis- (after Hope, 2002) humeral head small compared to living charadriiforms; dorsal tuber far from humeral head; dorsal tuber projected far from shaft; broad, flat surface between proximal tubers; capital groove ended posteriorly by shallow sulcus; transverse groove distal to humeral head; deep depressions for m. humerotriceps in pneumotricipital fossa; raised scar near base of ventral tubercle.
Comments- This was originally identified as a phalacrocoraciid ('graculid') by Marsh (1872), though Shufeldt (1915) thought it was a charadriine or scolopacine charadriiform ('limicoline'). Because of this, Shufeldt suggested the name Limosavis would be more appropriate, but this is not allowed by the ICZN. Contra Olson and Parris (1987), this was used in combination with velox by Shufeldt on page 76. Hope (2002) placed Graculavus close to or within Charadriiformes, though Mayr (2009) noted strong resemblance to presbyornithids.
Shufeldt (1915) incorrectly listed Graculavus idahensis as being named by Marsh in 1870, but Marsh actually named Graculus idahensis. The latter species is based on a proximal carpometacarpus (YPM 527) from the Pliocene of Idaho, and is currently known as Phalacrocorax idahensis (Marsh, 1870) Shufeldt, 1915 though no modern analysis has been attempted.
References- Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary formations of the United States. American Journal of Science, series 2. 49, 205-217.
Marsh, 1872. Preliminary description of Hesperornis regalis, with notices of four other new species of Cretaceous birds. American Journal of Science, series 3. 3, 360-365.
Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences. 19, 1-110.
Olson and Parris, 1987. The Cretaceous Birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Mayr, 2009. Paleogene Fossil Birds. Springer Berlin Heidelberg. 262 pp.
G. velox Marsh, 1872
= Limosavis velox (Marsh, 1872) Shufeldt, 1915
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Navesink or basal Hornerstown Formation, New Jersey, US
Holotype
- (YPM 855) proximal humerus
Referred- ?(NJSM 11854) metacarpal II (51 mm) (Olson and Parris, 1987)
Diagnosis- (after Hope, 1999) 74% as large as G. augustus; area between ventral and dorsal tubercles relatively narrower and more concave.
Comments- Olson and Parris (1987) referred the partial carpometacarpus based on size only, so this assignment is questionable.
References- Marsh, 1872. Preliminary description of Hesperornis regalis, with notices of four other new species of Cretaceous birds. American Journal of Science, series 3. 3, 360-365.
Shufeldt, 1915. Fossil birds in the Marsh Collection of Yale University. Transactions of the Connecticut Academy of Arts and Sciences. 19, 1-110.
Olson and Parris, 1987. The Cretaceous Birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
G. augustus Hope, 1999
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (AMNH 25223) proximal humerus
Diagnosis- (after Hope, 1999) 35% larger than G. velox; area between ventral and dorsal tubercles relatively wider and flatter.
Comments- The holotype was discovered in 1985.
Reference- Hope, 1999. A new species of Graculavus from the Cretaceous of Wyoming (Aves: Neornithes). in Olson (ed.). Avian Paleontology at the Close of the 20th Century: Proceedings of the 4th International Meeting of the Society of Avian Paleontology and Evolution, Washington, DC, June 1996. Smithsonian Contributions to Paleobiology. 89, 261-266.

Telmatornithidae Cracraft, 1972
Reference- Cracraft, 1972. A new Cretaceous charadriiform family. Auk. 89, 36-46.
Telmatornis Marsh, 1870
T. priscus Marsh, 1870
= Telmatornis affinis Marsh, 1870
?= Graculavus pumilis Marsh, 1872
Late Maastrichtian, Late Cretaceous
Navesink Formation, New Jersey, US
Holotype
- (YPM 840) distal humerus
Referred- (YPM 845; holotype of Telmatornis affinis) distal humerus (Marsh, 1870)
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
basal Hornerstown Formation, New Jersey, US

(ANSP 15360) distal humerus (Olson and Parrish, 1987)
?(ANSP 15541) pedal phalanx II-1 (14.6 mm) (Olson and Parrish, 1987)
?(NJSM 11853) distal tarsometatarsus (Olson and Parrish, 1987)
?(NJSM 11900) proximal ulna (Olson and Parrish, 1987)
?(YPM 850; holotype of Graculavus pumilis) proximal humerus, partial carpometacarpus, forelimb fragments (Marsh, 1872)
Comments- Marsh (1870) believed Telmatornis was most similar to rallids and ardeids, though it has been most often compared to rallids or burhinids since. Cracraft (1972) was the first to favor a charadriiform identity and synonymized affinis and priscus as the only notable difference was the slightly larger size (~7-19%) and robusticity of priscus (contra Hope 2002, Shufeldt 1915 felt synonymy was possible but not determinable due to sample size). Olson and Parris (1987) also referred the holotypes of Graculavus pumilis and Palaeotringa vetus to this taxon, but Hope (2002) found vetus to be dissimilar to charadriiforms based on a new specimen from the Lance Formation. While Hope (2002) agrees pumilis is probably synonymous with priscus, the referral of the ulna, tarsometatarsus and phalanx are only based on size and similarity to burhinids. Hope (2002) found Telmatornis to share several characters with charadriiforms that are also found other taxa and are often developed to a lesser degree in crown members of the order.
The Graculavus pumilis holotype was found to be non-avian by Clarke (2002).
References- Marsh, 1870. Notice of some fossil birds from the Cretaceous and Tertiary formations of the United States. American Journal of Science, series 2. 49, 205-217.
Marsh, 1872. Preliminary description of Hesperornis regalis, with notices of four other new species of Cretaceous birds. American Journal of Science, series 3. 3, 360-365.
Cracraft, 1972. A new Cretaceous charadriiform family. Auk. 89, 36-46.
Olson and Parris, 1987. The Cretaceous Birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Clarke, 2002. The morphology and systematic position of Ichthyornis Marsh and the phylogenetic relationships of basal Ornithurae. Ph.D. dissertation, Yale University, New Haven, CT. 532 pp.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.

"Lonchodytes" pterygius Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (UCMP 53961) distal carpometacarpus
Comments- Brodkorb (1963) initially described pterygius in his new genus Lonchodytes, interpreted as a new family of gaviifiorm. It shares no elements with the type species, L. estesi, and was only referred to the genus based on both species being contemporaneous and supposedly resembling loons. Similarly, it was only diagnosed relative to Gavia and separated from L. estesi based on its smaller size. Olson and Feduccia (1980) considered it indeterminate, and Cracraft (1982) thought it didn't have much phylogenetic information. Most recently, Hope (2002) believed it was indeterminate and not a gaviiform, but that its phalangeal facets resemble larine charadriiforms.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. International Ornithological Congress, Proceedings. 19, 55-70.
Olson and Feduccia, 1980. Relationships and evolution of flamingos (Aves: Phoenicopteridae). Smithsonian Contributions to Zoology. 316, 73 pp.
Cracraft, 1982. Phylogenetic relationships and monophyly of loons, grebes, and hesperornithiform birds, with comments on the early history of birds. Systematic Zoology. 31(1), 35-56.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.

unnamed possible charadriiform (Powell, 1987)
Maastrichtian, Late Cretaceous
Allen Formation, Rio Negro, Argentina
Material
- (PVL 4730) proximal tibiotarsus
Comments- This was first listed by Powell (1987) as Aves, then figured and identified as an ornithurine (sensu Chiappe) by Chiappe (1996). Chiappe noted while it was found in the same quarry as Limenavis, it was much smaller so unlikely to be the same taxon. Hope (2002) referred it to charadriiforms based on cnemial crest morphology, though noted this was symplesiomorphic compared to loons, procellariiforms and grebes. Thus the cnemial crest characters might be primitive for Coronaves.
References- Powell, 1987. Hallazgo de un dinosaurio hadrosaurido (Ornithischia: Ornithopoda) en la Formación Allen (Cretácico Superior) de Salitral Moreno, Prov. de Río Negro, Argentina. Congreso Geológico Argentino. 10(3), 149-152.
Chiappe, 1992. Osteologia y sistematica de Patagopteryx deferrariisi Alvarenga y Bonaparte (Aves) del Cretacico de Patagonia. Filogenia e historia biogeografica de las aves Cretacicas de America del Sur. PhD Thesis. Universidad de Buenos Aires.
Chiappe, 1996. Early avian evolution in the southern hemisphere: Fossil record of birds in the Mesozoic of Gondwana. Memoirs of the Queensland Museum. 39, 533-556.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.

undescribed possible charadriiform (Case and Tambussi, 1999)
Early Maastrictian, Late Cretaceous
Cape Lamb Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Material- (Saint Mary's College coll.) tarsometatarsus
Comments- Case and Tambussi (1999) referred this specimen to Charadriiformes, and it may be the same taxon as (or even belong to) Cordes' (2001) more complete specimen.
References- Case and Tambussi, 1999. Maestrichtian record of neornithine birds in Antarctica: Comments on a Late Cretaceous radiation of modern birds. Journal of Vertebrate Paleontology. 19(3), 37A.
Cordes, 2001. A basal charadriiform bird from the Early Maastrichtian of Cape Lamb, Vega Island, Antarctic Peninsula. Unpublished M.S. Thesis, SD School of Mines and Technology. 71 pp.

undescribed charadriiform (Cordes, 2001)
Early Maastrictian, Late Cretaceous
Cape Lamb Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Material- (VI 9901) two cervical vertebrae, two dorsal vertebrae, synsacrum, scapula, coracoids (one partial), partial sternum, humeri (one partial), proximal radius, proximal ulnae, carpometacarpis (one incomplete, one proximal), femora (one partial), proximal tibiotarsus, distal tibiotarsi, proximal tarsometatarsus
Comments- Cordes (2002) believed this was a charadriiform, potentially a burhinid.
References- Cordes, 2001. A basal charadriiform bird from the Early Maastrichtian of Cape Lamb, Vega Island, Antarctic Peninsula. Unpublished M.S. Thesis, SD School of Mines and Technology. 71 pp.
Cordes, 2002. A new charadriiform avian specimen from the Early Maastrichtian of Cape Lamb, Vega Island, Antarctic Peninsula. Journal of Vertebrate Paleontology. 22(3), 46A.

Natatores Illiger, 1811
= Aequornithes Mayr, 2010
= Aequornithia Cracraft, 2013

Gaviiformes Wetmore and Miller, 1926

Neogaeornis Lambrecht 1929
N. wetzeli Lambrecht 1929
Campanian-Maastrichtian, Late Cretaceous
Quiriquina Formation, Chile
Holotype
- (GPMK 123) tarsometatarsus (~63 mm)
Referred- ? tarsometatarsus (Oliver Schneider, 1940)
Comments- The holotype was found in 1923-1924 and placed in Colymbo-Podicipediformes by Lambrecht, which containeed loons, grebes and taxa recognized today as basal hesperornithines.
References- Lambrecht, 1929. Neogaeornis wetzeli n. g. n. sp., der erste Kreidevogel der suedlichen Hemisphaere. Palaeontologische Zeitschrift. 11, 121-129.
Olver Schneider, 1940. La fauna fosil de Gualpen. Revista Chilena de Historia Natural Pura y Aplicada. 44, 49-54.
Olson, 1992. Neogaeornis wetzeli Lambrecht, a Cretaceous loon from Chile (Aves, Gaviidae). Journal of Vertebrate Paleontology. 12(1), 122-124.

Polarornis Chatterjee, 2002
= "Polarornis" Chatterjee, 1997
P. gregorii Chatterjee, 2002
Late Maastrictian, Late Cretaceous
Lower Sandwich Bluff Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Holotype- (TTU P 9265) (~600 mm) partial skull (~180 mm), partial sixth cervical neural arch, seventh cervical vertebra (16 mm), eighth cervical vertebra, ninth cervical vertebra, sternal fragment, four partial sternal ribs, femora (one proximal; 62 mm), proximal tibiotarsus fused to proximal fibula
Referred- (MLP 96-I-6-2) incomplete femur, two proximal tibiotarsi, proximal fibula, pedal phalanx (Reguero et al., 2013; described by Acosta Hospitaleche and Gelfo, 2015)
(MLP 96-I-6-3) distal tibiotarsus (Reguero et al., 2013)
(MLP 96-I-6-4) distal femur (Reguero et al., 2013)
Comments- This specimen was found in 1983 and initially reported as an early loon by Chatterjee (1989, 1997), who unofficially named it "Polarornis" in the latter publication. It was officially named and described later by Chaterjee (2002). Both Olson (1992) and Hope (2002) believe the specimen to be a loon, though Martin (1998) and Feduccia (1999) were skeptical. The former thought it may be a penguin, while Feduccia also entertained the possibility it is a hesperornithine. It should be noted though that these opinions were all published prior to Polarornis' description, and that while Olson and Hoe had viewed the specimen, Martin and Feduccia's opinions were based on the schematic illustrations in Chatterjee's (1997) popular book. While Mayr says Polarornis "significantly differs from modern loons in several characters" and criticizes Chatterjee's misleading portrayal of the specimen's completeness, he does not actually suggest an alternative placement. Olson and Mayr suggested it could be synonymous with Neogaeornis, but this cannot be proven as Polarornis does not preserve the tarsometatarsus. Acosta Hospitaleche and Gelfo (2015) added Polarornis to Livezey and Zusi's large morphological matrix and found it it be a pan-gaviiform.
References- Chatterjee, 1989. The oldest Antarctic bird. Journal of Vertebrate Paleontology. 8(3), 11A.
Olson, 1992. Neogaeornis wetzeli Lambrecht, a Cretaceous loon from Chile (Aves, Gaviidae). Journal of Vertebrate Paleontology. 12(1), 122-124.
Chatterjee, 1997. The Rise of Birds. Baltimore: Johns Hopkins University Press. 312 pp.
Chinsamy, Martin and Dodson, 1998. Bone microstructure of the diving Hesperornis and the volant Ichthyornis from the Niobrara Chalk of western Kansas. Cretaceous Research. 19(2), 225-235.
Martin, 1998.
Feduccia, 1999. The Origin and Evolution of Birds. 2nd edition. Yale University Press. 466 pp.
Chatterjee, 2002. The morphology and systematics of Polarornis, a Cretaceous loon (Aves: Gaviidae) from Antarctica. In Zhou and Zhang (eds). Proceedings of the 5th Symposium of the Society of Avian Paleontology and Evolution, Beijing, 1-4 June 2000. Beijing: Science Press. 125-155.
Mayr, 2004. A partial skeleton of a new fossil loon (Aves, Gaviiformes) from the Early Oligocene of Germany with preserved stomach content. Journal of Ornithology. 45, 281-286.
Reguero, Goin, Acosta Hospitaleche, Dutra and Marenssi, 2013. Late Cretaceous/Paleogene west Antarctica terrestrial biota and its intercontinental affinities. Springer Briefs in Earth System Sciences. 120 pp.
Acosta Hospitaleche and Gelfo, 2015. New Antarctic findings of Upper Cretaceous and Lower Eocene loons (Aves: Gaviiformes). Annales de Paléontologie. 101(4), 315-324.
P? sp. nov. (Chatterjee, Martinioni, Novas, Mussel and Templin, 2006)
Late Maastrictian, Late Cretaceous
Lower Sandwich Bluff Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Material- specimen including forelimb elements, hindlimb elements including femur and tibiotarsus
Comments- Chatterjee et al. (2006) state the wing is well developed and performed computer simulations to show this specimen was a powerful flier, which may indicate it was not that closely related to P. gregorii, as the latter has thick bone walls more similar to flightless birds.
Reference- Chatterjee, Martinioni, Novas, Mussel and Templin, 2006. A new fossil loon from the Late Cretaceous of Antarctica and early radiation of foot-propelled diving birds. Journal of Vertebrate Paleontology. 26(3), 49A.

unnamed Gaviiformes (Acosta Hospitaleche and Gelfo, 2015)
Early Maastrictian, Late Cretaceous
Cape Lamb Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Material- ?(MLP 98-I-10-27) incomplete tarsometatarsus
(MLP 98-I-10-47) incomplete tarsometatarsus
?(MLP 98-I-10-49) distal tibiotarsus
(MLP 98-I-10-50) incomplete tarsometatarsus
(MLP 98-I-10-51) proximal femur
(MLP 98-I-10-52) incomplete tarsometatarsus
?(MLP 98-I-10-53) distal tibiotarsus
?(MLP 98-I-10-54) incomplete tarsometatarsus
(MLP 98-I-10-60) partial pedal phalanx
(MLP 98-I-10-61) partial pedal phalanx
(MLP 98-I-10-76) incomplete tarsometatarsus
Comments- Acosta Hospitaleche and Gelfo (2015) state MLP 98-I-10-50, 52 and 76 are similar, so may be conspecific.
Reference- Acosta Hospitaleche and Gelfo, 2015. New Antarctic findings of Upper Cretaceous and Lower Eocene loons (Aves: Gaviiformes). Annales de Paléontologie. 101(4), 315-324.

unnamed Gaviiformes (Acosta Hospitaleche and Gelfo, 2015)
Late Maastrictian, Late Cretaceous
Lower Sandwich Bluff Member of the Lopez de Bertodano Formation, Vega Island, Antarctica

Material- (MLP 98-I-10-48) distal tibiotarsus
(MLP 98-I-10-59) partial tibiotarsus
Reference- Acosta Hospitaleche and Gelfo, 2015. New Antarctic findings of Upper Cretaceous and Lower Eocene loons (Aves: Gaviiformes). Annales de Paléontologie. 101(4), 315-324.

Procellariimorphae Livezey and Zusi, 2007
= Austrodyptornithes Yuri, Kimball, Harshman, Bowie, Braun, Chojnowski, Han, Hackett, Huddleson, Moore, Reddy, Sheldon, Steadman, Witt and Braun, 2013

Procellariiformes Furbringer, 1888

Lonchodytidae Brodkorb, 1963
Lonchodytes Brodkorb, 1963
L. estesi Brodkorb, 1963
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (UCMP 53954) distal tarsometatarsus
Comments- Brodkorb (1963) originally described this as belonging to a new family of loons, but only stated differences from gaviids, not gaviiform synapomorphies. Olson and Feduccia (1980) stated it was more similar to Charadrii than gaviids based on three symplesiomorphies and also noted Brodkorb no longer believed it was gaviiform. Cracraft (1982) excluded Lonchodytes from his Gaviomorphae, which is today recognized as a polyphyletic assemblage of diving forms (hesperornithines, loons, grebes). Hope (2002) believed this was most similar to procellariids and referred it to Procellariiformes based on seven characters, though she noted four were also present in grebes, and a different four were present in alcid charadriiforms.
References- Brodkorb, 1963. Birds from the Upper Cretaceous of Wyoming. in Sibley (ed.). Proceedings of the XIII International Ornithological Congress. 50-70.
Olson and Feduccia, 1980. Relationships and evolution of flamingos (Aves: Phoenicopteridae). Smithsonian Contributions to Zoology. 316, 73 pp.
Cracraft, 1982. Phylogenetic relationships and monophyly of loons, grebes, and hesperornithiform birds, with comments on the early history of birds. Systematic Zoology. 31(1), 35-56.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Tytthostonychidae Olson and Parris, 1987
Tytthostonyx Olson and Parris, 1987
T. glauconiticus Olson and Parris, 1987
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US
Holotype
- (NJSM 11341) incomplete humerus (~110 mm)
Diagnosis- (after Olson and Parris, 1987) ectepicondylar spur intermediate in development between Pelecaniformes and other Procellariiformes; deltopectoral crest extends much farther distally than other Procellariiformes or Limnofregata; ventral condyle very rounded, extending distally well past dorsal condyle.
Comments- The holotype was discovered in 1973 and described by Olson and Parris (1987) as a basal procellariiform also similar to Limnofregata. This was interpreted as supporting a procellariiform-pelecaniform clade and a basal placement for Fregatidae inside Pelecaniformes. Molecular studies indicate sphenisciforms are more closely related to procellariiforms though, with ciconiids sister to pelecaniforms. Bourdon et al. (2008) stated Tytthostonyx was definitely not a procellariiform because "its condylae are shorebird-like and very similar to those of Lithoptila", and possibly closely related to prophaethontids. Yet adding Tytthostonyx to Smith's (2010) pelecaniform matrix found it to clade with procellariiforms to the exclusion of other taxa, including prophaethontids.
References- Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.
Bourdon, Mourer-Chauviré, Amaghzaz and Bouya, 2008. New specimens of Lithoptila abdounensis (Aves, Prophaethontidae) from the Lower Paleogene of Morocco. Journal of Vertebrate Paleontology. 28, 751-761.
Smith, 2010. Phylogenetic analysis of Pelecaniformes (Aves) based on osteological data: Implications for waterbird phylogeny and fossil calibration studies. PLoS ONE. 5(10), e13354.

unnamed possible procellariiform (Olson and Parris, 1987)
Late Maastrichtian-Early Danian, Late Cretaceous-Early Paleocene
Hornerstown Formation, New Jersey, US

Material- (ANSP 15713) distal ulna
References- Olson and Parris, 1987. The Cretaceous birds of New Jersey. Smithsonian Contributions to Paleobiology. 63, 22 pp.

Diomedeidae Gray, 1840

undescribed diomedeid (Kurochkin, 1995)
Early Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia
Material
- furcular fragment
Comments- Hope (2002) confirms this is consistant with a diomedeid identification.
References- Kurochkin, 1995. 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.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Steganograllatores Livezey and Zusi, 2007

Pelecaniformes Sharpe, 1891
Diagnosis- (after Hope, 2002) ventral rim of brachial fossa very narrow; attachment for ventral collateral ligament small; flexor process very short.
= Pelecani Wetmore, 1930

Steganopodes Illiger, 1811
= Suloidea Reichenbach, 1849 sensu Mathews, 1919

Sulida Sibley and Ahlquist, 1990

Phalacrocoracoidea Bonaparte, 1853 sensu Mathews, 1919

Phalacrocoracidae Bonaparte, 1853

unnamed possible phalacrocoracid (Hope, 2002)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US

Material- (AMNH 25272) femur (~47 mm)
Comments- Hope (2002) refers this specimen to Phalacrocoracidae based on several characters, but Longrich et al. (2011) stated they most likely belong to basal hesperornithines from the same formation.
References- Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Longrich, Tokaryk and Field, 2011. Mass extinction of birds at the Cretaceous-Paleogene (K-Pg) boundary. Proceedings of the National Academy of Sciences. 108(37), 15253-15257.

undescribed phalacrocoracid (Kurochkin, 1995)
Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia

Material- (PIN coll.) scapula
Comments- Hope (2002) confirms Kurochkin's (1995) assignment of this specimen to Phalacrocoracidae based on- coracoid tubercle absent (also in other suloids); impression for M. deltoideus minor deep and recurved around the tip of the acromion; acromion elongate, broad, flat and recurved at tip.
References- Kurochkin, 1995. Synopsis of Mesozoic birds and early evolution of Class Aves. Archaeopteryx. 13, 47-66.
Kurochkin, 1995. The assemblages of the Cretaceous birds in Asia. In Sun and Wang (eds.). Sixth Symp. Mesozoic Terrestrial Ecosystems and Biota, Short papers. China Ocean Press. 203-208.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.

Inopinaves Prum, Berv, Dornburg, Field, Townsend, Lemmon and Lemmon, 2015

Dendrornithes Furbringer, 1888
= Telluraves Yuri, Kimball, Harshman, Bowie, Braun, Chojnowski, Han, Hackett, Huddleson, Moore, Reddy, Sheldon, Steadman, Witt and Braun, 2013

Eutelluraves Prum, Berv, Dornburg, Field, Townsend, Lemmon and Lemmon, 2015

Australavis Ericson, 2012
= Psittacopasserria Jarvis et al., 2014

Eufalconimorphae Suh, Paus, Kiefmann, Churakov, Franke, Brosius, Kriegs and Schmitz, 2011

Psittacopasserae Suh, Paus, Kiefmann, Churakov, Franke, Brosius, Kriegs and Schmitz, 2011
= Passerimorphae Sibley, 1988 sensu Jarvis et al., 2014

Psittaciformes Wagler, 1830

unnamed possible psittaciform (Stidham, 1998)
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Material
- (UCMP 143274) anterior dentary
Comments- This specimen has been highly controversial. Initially described as a parrot most similar to loriines by Stidham (1998), Dyke and Mayr (1999) dispute the strength of this identification, though Hope (2002) believes it probably came from a parrot. The basic facts are that morphologically, the specimen indeed most similar to loriine psittacids, but that a series of stem-psittaciforms with more plesiomorphic dentaries are known from the Tertiary, making the Lance specimen unexpectedly early and indicative of numerous ghost lineages. Thus is it possible the dentary represents another taxon convergent on loriine psittacids, though contra Mayr (2009) this is likely to be an avian lineage as opposed to an oviraptorosaur.
References- Stidham, 1998. A lower jaw from a Cretaceous parrot. Nature. 396, 29-30.
Dyke and Mayr, 1999. Did parrots exist in the Cretaceous period? Nature. 399, 317-318.
Hope, 2002. The Mesozoic radiation of Neornithes. in Chiappe and Witmer, eds. Mesozoic Birds: Above the Heads of Dinosaurs. 339-388.
Mayr, 2009. Paleogene Fossil Birds. Springer Berlin Heidelberg. 262 pp.