Paraves Sereno, 1997
Definition- (Passer domesticus <- Oviraptor philoceratops) (Holtz and Osmolska, 2004; modified from Sereno, 1998)
= Troodontidae sensu Varricchio, 1997
Definition- (Troodon formosus, Saurornithoides mongoliensis, Borogovia gracilicrus, Sinornithoides youngi <- Ornithomimus velox, Oviraptor philoceratops)
= Tetrapterygidae Chatterjee, 2015
Comments- Chatterjee (2015) proposed the family Tetrapterygidae for a clade including Microraptor, Xiaotingia, Anchiornis and Aurornis. However, as noted by Martyniuk (online, 2015), according to ICZN Article 11.7.11 a family-group name must be "formed from the stem of an available generic name" which "must be a name then used as valid in the new family-group taxon." As Chatterjee did not intend for Tetrapterygidae to include a genus Tetrapteryx, it is invalid. Furthermore, Tetrapteryx has already been used for a genus of gruid (Thunberg, 1818), corrently considered a synonym of Anthropoides. Finally, if Microraptor is in a family, the family must be named Microraptoridae because that family was already erected by Longrich and Currie (2009).
The topology of Paraves is controversial, with Senter et al. (2012) finding Deinonychosauria (Troodontidae+Dromaeosauridae), Foth et al. (2014) and Lee et al. (2014) finding avialan troodontids, while Brusatte et al. (2014) found a trichotomy. A pairing of Dromaeosauridae and birds (Eumaniraptora) to the exclusion of troodontids is not common recently.
References- Thunberg, 1818. Tetrapteryx capensis, ett nytt Fogelslaegte. Kongliga Svenska Vetenskaps Academiens nya Handlingar. 1818(2), 242-245.
Larson, 2009. Multivariate analyses of small theropod teeth and implications for paleoecological turnovers through time. Journal of Vertebrate Paleontology. 29(3), 132A.
Senter, Kirkland, DeBlieux, Madsen and Toth, 2012. New dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the evolution of the dromaeosaurid tail. PLoS ONE. 7(5), e36790.
Sorkin, 2012. Aerial ability in basal Deinonychosauria. Journal of Vertebrate Paleontology. Program and Abstracts 2012, 176-177.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.
Chatterjee, 2015. The Rise of Birds: 225 Million Years of Evolution. Second Edition. Johns Hopkins University Press. 392 pp.
Martynuik, online 2015. http://dinogoss.blogspot.com/2015/05/the-crane-and-microraptor.html

Eumaniraptora Padian, Hutchinson and Holtz, 1997
Definition- (Deinonychus antirrhopus + Passer domesticus) (Maryanska et al., 2002; modified from Padian, Hutchinson and Holtz, 1999)
Other definitions- (Passer domesticus <- Troodon formosus) (modified from Agnolin and Novas, 2013)
(Dromaeosaurus albertensis + Passer domesticus) (Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013)
= Aves sensu Chiappe, 1992
Definition- (Archaeopteryx lithographica + Passer domesticus)
= "Eumaniraptora" Holtz, 1992
= Maniraptora sensu Padian and Holtz, 1995
Definition- (Dromaeosaurus albertensis + Passer domesticus)
= Deinonychosauria sensu Sereno, 1997
Definition- (Troodon formosus + Dromaeosaurus albertensis) (modified)
= Deinonychosauria sensu Sereno, 1998
Definition- (Troodon formosus + Velociraptor mongoliensis) (modified)
= Avialae sensu Gauthier and de Queiroz, 2001
Definition- (feathered wings homologous with Vultur gryphus and used for powered flight)
= Avialae sensu Gauthier and Wagner, 2001
Definition- (Archaeopteryx lithographica + Vultur gryphus)
= Palaeoaves Livezey and Zusi, 2007
= Ornithes Martyniuk, 2012
Definition- (Archaeopteryx lithographica + Passer domesticus)
= Ornithidesmiformes Martyniuk, 2012
Definition- (Ornithodesmus cluniculus, Dromaeosaurus albertensis, Troodon formosus <- Archaeopteryx lithographica) (Martyniuk, 2012)
= Avialae sensu Agnolin and Novas, 2013
Definition- (Archaeopteryx lithographica + Passer domesticus) (modified)
Comments- This is used as a shortcut for any node-based basic paravian clade, though most modern topologies would include dromaeosaurids, troodontids, archaeopterygids and (other) avialans in Eumaniraptora.
Holtz (1992) originally named Eumaniraptora in his unpublished thesis, but used it for what would now be called Maniraptoriformes- a clade containing paravians, oviraptorosaurs, ornithomimosaurs and also tyrannosaurids, but not Ornitholestes or Compsognathus. Padian et al. (1997) later officially named it as a smaller clade uniting deinonychosaurs and avialans, which has been the sense it is used in ever since.
Palaeoaves is used as a paraphyletic parvclass within Avialae by Livezey and Zusi (2007) that includes Archaeopteryx, Rahonavis, Confuciusornis, enantiornithines and Apsaravis, but not hesperornithines, Ichthyornis, lithornithids or Aves sensu stricto.
References- Holtz, 1992. An unusual structure of the metatarsus of Theropoda (Archosauria: Dinosauria: Saurischia) of the Cretaceous. Unpublished PhD thesis. Yale University. 347 pp.
Livezey and Zusi, 2007. Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion. Zoological Journal of the Linnean Society. 149 (1), 1-95.
Lamm, Ksepka, Stone and Clarke, 2008. Identifying differential size trends in Mesozoic birds using new data and a novel method. Journal of Vertebrate Paleontology. 28(3), 103A.
Bell, Chiappe and O'Connor, 2009. Ecological diversity of Mesozoic birds: Morphometric analysis with a phylogenetic perspective. Journal of Vertebrate Paleontology. 29(3), 61A.
Chinsamy-Turan, 2009. The bone microstructure of Mesozoic birds. Journal of Vertebrate Paleontology. 29(3), 77A.
Nudds and Dyke, 2009. Estimating the flight capabilities of extinct Mesozoic birds from their primary feather morphology. Journal of Vertebrate Paleontology. 29(3), 156A-157A.
O'Connor, 2009. A comprehensive phylogeny of Mesozoic birds. Journal of Vertebrate Paleontology. 29(3), 157A.
Weishampel and Habib, 2009. Flight morphology and launch dynamics of basal birds, and the potential for competition with pterosaurs. Journal of Vertebrate Paleontology. 29(3), 199A.
Wang, Dyke and Nudds, 2010. Inferring the flight styles of early birds and flight evolution from primary feather length. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 183A.
Dececchi and Larsson, 2011. The origin of wings. Journal of Vertebrate Paleontology. Program and Abstracts 2011, 97.
Wang, Dyke and Palmer, 2011. Scaling in size and stiffness of avian primary feathers: Implications for the strength of Mesozoic bird feathers. Journal of Vertebrate Paleontology. Program and Abstracts 2011, 211.
Dececchi, 2012. Patterns and processes at origin of birds: Macroevolutionary tempo and mode. Journal of Vertebrate Paleontology. Program and Abstracts 2012, 85-86.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Vernon, New Jersey. Pan Aves. 189 pp.
Mitchell, Makovicky and Gao, 2012. Paleoecology of the Jehol birds inferred from modern bird ecomorphology. Journal of Vertebrate Paleontology. Program and Abstracts 2012, 143.
O'Connor, 2012. Dietary evolution in Mesozoic birds. Journal of Vertebrate Paleontology. Program and Abstracts 2012, 151.
Dececchi, Habib and Larsson, 2013. Testing wing assusted incline running (WAIR): Investigating the terrestrial origin of the avian flight stroke. Journal of Vertebrate Paleontology. Program and Abstracts 2013, 113.
Field and Lynner, 2013. Precise inference of avialan flight ability from shoulder joint dimensions. Journal of Vertebrate Paleontology. Program and Abstracts 2013, 126.
Xu, Zhao and Han, 2013. Homeotic transformation in the evolution of the theropod semilunate carpal. Journal of Vertebrate Paleontology. Program and Abstracts 2013, 241.
Naish, 2014. The fossil record of bird behaviour. Journal of Zoology. 292(4), 268-280.
O'Connor and Zhou, 2014. Earliest stages in the evolution of the modern avian skeleton: Archaeopteryx and the Jehol avifauna compared. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 197.
Sanz, Serrano, Martin-Serra and Palmqvist, 2014. Revisiting size trends in early stem birds. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 221.
Serrano, Palmqvist, Martin-Serra and Sanz, 2014. Morphofunctional evolution of the humerus in the avian lineage. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 228.

Eumaniraptora incertae sedis

Boreonykus Bell and Currie, 2015
B. certekorum Bell and Currie, 2015
Late Campanian, Late Cretaceous
Wapiti Formation, Alberta, Canada
Holotype
- (RTMP 89.55.47) incomplete frontal (52.4 mm)
Diagnosis- (after Bell and Currie, 2015) supratemporal ridge on frontals forming acute angle (55 degrees) anteriorly.
Combination of- frontal elongate and slender; low supratemporal ridge forming arc that is concave relative to interfrontal suture in dorsal view; area immediately posterior to supratemporal ridge smooth and posteroventrally sloping.
Comments- Ryan and Russell (2001) listed the holotype frontal as "Saurornitholestes undescribed n. sp. (Currie pers. comm.)". Bell and Currie (2015) described this and other material (distal caudal RTMP 88.55.129, manual ungual UALVP 53597, and pedal ungual II RTMP 86.55.184) from the Pipestone Creek Pachyrhinosaurus lakustai bonebed as Boreonykus certekorum, noting that preserved elements are not duplicated and are properly proportioned to belong to one individual. The fourteen referred teeth are shed so were admitted to at least belong to another individual. When entered in Longrich and Currie's dromaeosaurid analysis, it emerged as a velociraptorine if the teeth were included, and a member of Velociraptorinae+Dromaeosaurinae if they were excluded. However, Cau (online, 2015) noted that given the paucity of remains and number of small Judithian theropod taxa, it should not be assumed that the frontal belongs to the same individual as the dromaeosaurid postcrania. Indeed, he reported that when the frontal is entered into his theropod supermatrix, it emerges in several position within Maniraptoriformes but never as a dromaeosaurid. My own analysis finds it to be a coelurosaur excluded from ornithomimosaurs, alvarezsauroids, therizinosaurs, oviraptorosaurs, unenlagiines, microraptorians, dromaeosaurines, derived troodontids and birds. As it is clearly not a member of contemporaneous clades known from frontals, Boreonykus may belong to one of the problematic taxa such as Richardoestesia or Paronychodon which are both placed in Paraves here. If I'm correct and Richardoestesia is a microraptorian, Boreonykus may be Paronychodon.
References- Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). In Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press. 279-297.
Bell and Currie, 2015. A high-latitude dromaeosaurid, Boreonykus certekorum, gen. et sp. nov. (Theropoda), from the upper Campanian Wapiti Formation, west-central Alberta. Journal of Vertebrate Paleontology. e1034359. DOI: 10.1080/02724634.2015.1034359.
Cau, online 2015. http://theropoda.blogspot.com/2015/12/boreonykus-e-un-dromaeosauridae.html

Cretaaviculus Bazhanov, 1969
C. sarysuensis Bazhanov, 1969
Santonian, Late Cretaceous
Bostobe Formation, Kazakhstan
Holotype
- contour feather (17 mm)
Comments- This specimen is a small, asymmetric contour feather with a length of 17 mm and a width of 4.8-5.5 mm. The barbs are at a 20 degree angle to the shaft. The asymmetry suggests it is a paravian. Nessov (1992) considers it indeterminate, which is true so far as feather characteristics cannot be used to diagnose Mesozoic birds.
References- Bazhanov, 1969. [On the record of a bird remain living in the Cretaceous in the USSR]. Tezisy Dokladov XV Sessii Vsesoyuznogo Paleontologicheskogo Obshchestva. 5-6.
Shillin and Romanova, 1978. [Senonian floras of Kazakhstan]. Alma-Ata: Kairat Publishing. 176 pp.
Nessov, 1992. Mesozoic and Paleogene birds of the USSR and their paleoenvironments. in Campbell (ed). Papers in Avian Paleontology Honoring Pierce Brodkorb. 465-478.

Elopterygidae Lambrecht, 1933
Elopteryginae Lambrecht, 1933 sensu Le Loeuff, Buffetaut, Mechin and Mechin-Salessy, 1992
Comments- Lambrecht (1933) erected Elopterygidae within Sulida (his Sulides), for Elopteryx (including what would become the types of Bradycneme and Heptasteornis), Eostega and Actiornis. Eostega is an Eocene taxon known from incomplete mandibles which cannot be compared to Elopteryx, but have been recently referred to Sulidae (Mlikovsky, 2007). Actiornis is also Eocene and known from a proximal ulna which cannot be compared to Elopteryx either, and has been referred to Threskiornithidae since Harrison and Walker (1976). Le Loeuff et al. (1992) resurrected the family-level taxon for what they considered dromaeosaurs, again synonymizing Elopteryx, Bradycneme and Heptasteornis, and also referring a femur (MDE-D203) from Metisson (Fox-Amphoux, Var), and an anterior dorsal vertebra (MDE-D01), posterior sacral vertebra (MDE coll.) and several fragmentary dorsal ribs from Roques-Hautes (Bouches-du-Rhone). These materials have since been referred to Variraptor (Le Loeuff and Buffetaut, 1998). Le Loeuff et al. largely grouped these remains together based on geography and the peculiar wrinkled bone texture, but this has since been described in a parvicursorine distal femur (FGGUB R.1957) and the basal ornuthirine Balaur, both from Romania. Thus it seems to be related to locality instead of phylogeny.
References- Lambrecht, 1933. Handbuch der Palaeornithologie. Gebrüder Borntraeger. 1024 pp.
Harrison and Walker, 1976. Birds of the British Upper Eocene. Zoological Journal of the Linnean Society. 59(4), 323-351.
Le Loeuff, Buffetaut, Mechin and Mechin-Salessy, 1992. The first record of dromaeosaurid dinosaur (Saurichia, Theropoda) in the Maastrichtian of Southern Europe: palaeobiogeographical implications. Bulletin de la Societe Geologique de France. 163(3), 337-343.
Le Loeuff and Buffetaut, 1998. A new dromaeosaurid theropod from the Upper Cretaceous of Southern France. Oryctos. 1, 105-112.
Mlikovsky, 2007. Taxonomic identity of Eostega lebedinskyi Lambrecht, 1929 (Aves) from the Middle Eocene of Romania. Annalen des Naturhistorischen Museums in Wien. 109A, 19-27.
Elopteryx Andrews, 1913
E. nopcsai Andrews, 1913
Late Maastrichtian, Late Cretaceous
Sinpetru Beds, Romania
Holotype
- (BMNH A1234) proximal femur (~150 mm)
Paratype- (BMNH A1235) proximal femur (~150 mm) (Lambrecht, 1929)
Comments- Andrews (1913) originally described Elopteryx as a pelecaniform, referring the distal tibiotarsus BMNH A4329 to the same individual. Lambrecht (1929) referred two more distal tibiotarsi (BMNH A1528 and 1588) to it, as well as an additional proximal femur (BMNH A1234). Later, Lambrecht (1933) created the family Elopterygidae for the genus. Harrison and Walker (1975) removed the tibiotarsi, making them the type specimens of Bradycneme and Heptasteornis. Grigorescu and Kessler (1981) referred a distal femur (FGGUB R.351) to this taxon, which was reidentified as a ceratosaur by Csiki and Grigorescu (1998), then more certainly as a distal hadrosaurid metatarsal by Kessler et al. (2005). Jurcsak and Kessler (1986) reported a skull (FGGUB 1007) they referred to Elopteryx which supposedly supports an assignment to Pelecaniformes, but this has turned out to be from a sauropod (Csiki, pers. comm. 2007; illustrated in Weishampel et al., 1991). Le Loeuff et al. (1992) resynonymized Heptasteornis and Bradycneme with Elopteryx based on their bone texture. They also described a femur (MDE-D203), anterior dorsal vertebra (MDE-D01), posterior sacral vertebra (MDE coll.) and several fragmentary dorsal ribs from the Gres a Reptiles Formation of France which they believed were congeneric or at least related to Elopteryx. Le Loeuff et al. believed these remains were most closely related to dromaeosaurids, though perhaps deserving their own family or subfamily (Elopterygidae or Elopteryginae). Le Loeuff and Buffetaut (1998) referred the two vertebrae to their new dromaeosaurid genus Variraptor. The femur was only stated to share general characteristics with Elopteryx (reduced fourth trochanter, posterior trochanter, "shape and size") while differing in having a linear capital ligament fossa and absent fourth trochanter. It probably belongs to a distinct taxon of maniraptoran, and as the tibiotarsi and vertebrae are not even comparable to Elopteryx, the concept of a European clade of elopterygines or elopterygids is morphologically baseless. The Elopteryx holotype was identified as a derived maniraptoran by Csiki and Grigorescu (1998) and later as a troodontid or non-ornithuromorph pygostylian by Naish and Dyke (2004). Kessler et al. (2005) describe a mononykine distal femur (FGGUB R.1957) as Elopteryx based on bone texture, synonymizing Heptasteornis and Bradycneme with the genus again, and refer the taxon to Alvarezsauridae. I prefer to assign the femur to the mononykine Heptasteornis, while keeping Elopteryx separate as it differs from alvarezsaurids in some ways (posterior trochanter and capital ligament fossa present). An unpublished analysis based on TWG characters suggests Elopteryx is most similar to dromaeosaurids and non-enantiornithine avialans, so it's retained as Eumaniraptora incertae sedis here.
References- Andrews, 1913. On some bird remains from the Upper Cretaceous of Transylvania. Geological Magazine. 5, 193-196.
Lambrecht, 1929. Mesozoische und tertiare Vogelreste aus Siebenburgen. In Csiki (ed.). Xe Congres International de Zoologie. 1262-1275.
Lambrecht, 1933. Handbuch der Palaeornithologie. Gebrüder Borntraeger. 1024 pp.
Harrison and Walker, 1975. The Bradycnemidae, a new family of owls from the Upper Cretaceous of Romania. Palaeontology. 18(3), 563-570.
Grigorescu and Kessler, 1981. A new specimen of Elopteryx nopcsai from the dinosaurian beds of Hateg Basin. Revue Roumaine de Geologie, Geophysique et Geographie, Geologie. 24, 171-175.
Jurcsak and Kessler, 1986. The evolution of the Roumanien bird fauna, Part I. The history of the studies. Crisia 16, 577-615, Oradea. [in Roumanian, with English abstract]
Kessler, 1987. New contributions to the knowledge about the Lower and Upper Cretaceous birds from Romania. Occasional Papers of the Tyrrell Museum of Palaeontology. 3, 133-135.
Weishampel, Grigorescu and Norman, 1991. The dinosaurs of Translyvania.National Geographic Research and Exploration. 7(2), 196-215.
Le Loeuff, Buffetaut, Mechin and Mechin-Salessy, 1992. The first record of dromaeosaurid dinosaur (Saurichia, Theropoda) in the Maastrichtian of Southern Europe: palaeobiogeographical implications. Bulletin de la Societe Geologique de France. 163(3), 337-343.
Le Loeuff and Buffetaut, 1998. A new dromaeosaurid theropod from the Upper Cretaceous of Southern France. Oryctos. 1, 105-112.
Csiki and Grigorescu, 1998. Small Theropods from the Late Cretaceous of the Hateg Basin (Western Romania) - an unexpected diversity at the top of the food chain. Oryctos. 1, 87-104.
Naish and Dyke, 2004. Heptasteornis was no ornithomimid, troodontid, dromaeosaurid or owl: the first alvarezsaurid (Dinosauria: Theropoda) from Europe. Neus Jahrbuch für Geologie und Paläontologie. 7, 385-401.
Kessler, Grigorescu and Csiki, 2005. Elopteryx revisited - a new bird-like specimen from the Maastrichtian of the Hateg Basin. Acta Palaeontologica Romaniae. 5, 249-258.

Hulsanpes Osmolska, 1982
H. perlei Osmolska, 1982
Middle Campanian, Late Cretaceous
Baron Goyot Formation, Mongolia
Holotype
- (ZPAL MgD-I/173) (~360 mm; juvenile) (?)otico-occipital fragment, metatarsal II (~34 mm), phalanx II-1 (~6.5 mm), proximal phalanx II-2, metatarsal III (~39 mm), proximal phalanx III-1, metatarsal IV (~36 mm)
Diagnosis- metatarsal III expanded proximally; metatarsus excavated on plantar surface.
Comments- This specimen was discovered in 1970 and described twelve years later. Using Mei as a guide, we can estimate Hulsanpes was about 360 mm long, but it was juvenile based on the rough bone texture and the badly abraded articular joints.
The metatarsus "lacks even incipient fusion" (contra Holtz), and is non-arctometatarsalian to the point that metatarsal III expands proximally. It is fairly slender and metatarsal III is slightly more robust than the others. Distally, metatarsal III flattens and widens to partially overlap metatarsal II. The metatarsus is concave posteriorly, with metatarsal III inset compared to the others. The distal end of metatarsal III is shallowly grooved with a symmetrical ginglymus. The distal end of metatarsal IV is transversely flattened and diverges from metatarsal III. The articular surface is narrow and undivided, with a groove posterior to it.
Pedal phalanx I-1 is rather similar to Deinonychus. The proximal end has an elongate articular surface divided asymmetrically by a ridge, showing that the articulation of metatarsal II was ginglymoid. The distal end is divided asymmetrically by a long groove that extends more dorsally than ventrally. The medial condyle is a bit wider and lower. The ligamental fossae are deep and the lateral one is more centrally placed.
Although the second digit could hyperextend, the proximoventral heel of phalanx II-2 was not well-developed.
Relationships- Osmolska allied this species with dromaeosaurids based on the ginglymoid second and third metatarsals and subequally developed metatarsals II and IV, but noted it resembled troodontids in the narrow metatarsus and weakly developed second pedal digit. She dismissed avian origins based on the lack of fusion. Senter et al. (2004) is the only published analysis to include Hulsanpes, which emerged as a dromaeosaurid because they miscoded the ginglymoid metatarsal II as absent in Sinovenator. Chiappe and Norell (Norell pers. comm. to Currie, 2001) think Hulsanpes is not a dromaeosaurid, but from "another more speciose branch of the Maniraptora". Holtz (DML, 1995) wrote that the metatarsals and distal tarsals are fused at least distally in this species, like birds. He also cryptically said "future work may show why this is no surprise....". Then in May of 1997 (DML), Holtz said that Hulsanpes is almost certainly not a dromaeosaurid. The description specifically states that the metatarsus is unfused however, contradicting Holtz's statement (but not his conclusion). Adding the genus to a TWG supermatrix excludes it from Ornithomimosauria, Parvicursorinae, Therizinosauria, Oviraptorosauria, Sinornithoides+Troodontinae, Dromaeosauridae, Archaeopterygidae, Confuciusornithidae, Enantiornithes and Ornithuromorpha. Thus it may be a basal troodontid or basal bird.
References- Osmolska, 1982. Hulsanpes perlei n. g. n. sp. (Deinonychosauria, Saurischia, Dinosauria) from the Upper Cretaceous Barun Goyot Formation of Mongolia. Neues Jahrbuch fur Geologie und Palaeontologie, Monatshefte. 1982(7), 440-448.
http://dml.cmnh.org/1995Sep/msg00030.html
http://dml.cmnh.org/1997May/msg00576.html
Currie, 2001. Theropod dinosaurs from the Cretaceous of Mongolia. in Benton, Shishkin, Unwin and Kurochkin, eds. The Age of Dinosaurs in Russia and Mongolia. 434-455.
Senter, Barsbold, Britt and Burnham, 2004. Systematics and evolution of Dromaeosauridae. Bulletin of Gunma Natural History Museum. 8, 1-20.

Jinfengopteryginae Turner, Makovicky and Norell, 2012
Definition- (Jinfengopteryx elegans <- Sinovenator changii, Troodon formosus, Passer domesticus) (Turner, Makovicky and Norell, 2012)
= "Jinfengopteryginae" Turner, 2008
Comments- Turner (2008; later published as Turner et al., 2012) created this clade for Jinfengopteryx, IGM 100/1128 and 100/1323 within Troodontidae.
References- Turner, 2008. Phylogenetic relationships of paravian Theropods. PhD Thesis. Columbia University. 666 pp.
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and paravian phylogeny. Bulletin of the American Museum of Natural History. 371, 1-206.
Jinfengopteryx
Ji, Ji, Lu, You, Chen, Liu and Liu, 2005
J. elegans Ji, Ji, Lu, You, Chen, Liu and Liu, 2005
Early Aptian, Early Cretaceous
Qiaotou Member of the Huajiying Formation, Hebei, China

Holotype- (CAGS-IG-04-0801) (548 mm) skull (~68 mm), sclerotic plates, mandible, hyoids, twelve cervical vertebrae, cervical ribs, eleven dorsal vertebrae, dorsal ribs, gastralia, twenty-four caudal vertebrae (273 mm), chevrons, scapulae (47.09 mm), coracoid, furculae, humeri (49.22 mm), radii (42.44 mm), ulnae (43.31 mm), radiale, semilunate carpal, metacarpal I (8.77 mm), phalanx I-1 (18.83 mm), manual ungual I (17.75 mm), metacarpal II (21.37 mm), phalanx II-1 (15.26 mm), phalanx II-2 (21.07 mm), manual ungual II (17.32 mm), metacarpal III (~21 mm), phalanx III-1+III-2 (10 mm), phalanx III-3 (12.95 mm), manual ungual III (~14 mm), partial ilium (~49 mm), pubes, partial ischium, femora (70.32 mm), tibiae (100.5 mm), fibula (98.75 mm), proximal tarsus, metatarsus (~59 mm), pedal digit II, pedal digit III, pedal digit IV, feathers, gastroliths/eggs/seeds
Comments- Jin et al. (2008) reassign Jinfengopteryx's horizon to the Qiaotou Member of the Huajiying Formation, as opposed to the Qiaotau Formation which was stated in Ji et al. (2005). Ji et al.'s labeled "pterygoid" looks to be a parasphenoid rostrum, the "squamosal" part of the parietal. Turner (2008) redescribed the skull in his thesis.
Though Ji et al. (2005) assign it to the Archaeopterygidae, I first noted a resemblence to troodontids (Mortimer, DML 2005). Xu and Norell (2006) stated Jinfengopteryx was a possible troodontid based on "general body plan" and several undisclosed dental features. It has been most recently placed in basal Troodontidae (Brusatte et al., 2014; Lee et al., 2014) or basal Paraves (Foth et al., 2014).
References- Ji, Ji, Lu, You, Chen, Liu and Liu, 2005. First avialan bird from China (Jinfengopteryx elegans gen. et sp. nov.). Geological Bulletin of China. 24(3), 197-205.
Mortimer, DML 2005. http://dml.cmnh.org/2005Mar/msg00372.html
Xu and Norell, 2006. Non-avian dinosaur fossils from the Lower Cretaceous Jehol Group of western Liaoning, China. Geological Journal. 41(3-4), 419-437.
Ji and Ji, 2007. Jinfengopteryx compared to Archaeopteryx, with comments on the mosaic evolution of long-tailed avialan birds. Acta Geologica Sinica (English Edition). 81(3), 337-343.
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science Bulletin. 53(18), 2820-2827.
Turner, 2008. Phylogenetic relationships of paravian Theropods. PhD Thesis. Columbia University. 666 pp.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.

Xiaotingia Xu, You, Du and Han, 2011
X. zhengi Xu, You, Du and Han, 2011
Oxfordian, Late Jurassic
Tiaojishan Formation?, Liaoning, China
Holotype
- (STM 27-2) (820 g adult) skull (~61 mm to quadrate), mandible (62 mm), (cervical series 80 mm) ten cervical vertebrae, cervical ribs, (dorsal series 118 mm) thirteen dorsal vertebrae, dorsal ribs, gastralia, synsacrum, three proximal caudal vertebrae, scapulae (55 mm), partial coracoid, furcula (42 mm across), humeri (71 mm), radii (63 mm), ulnae (65 mm), semilunate carpal, metacarpal I (10 mm), phalanges I-1 (21 mm), manual unguals I (14 mm), metacarpals II (24 mm), phalanges II-1 (15 mm), phalanges II-2 (25 mm), manual unguals II (14 mm), metacarpals III (24 mm), phalanges III-1 (8 mm), phalanges III-2 (4 mm), phalanges III-3 (15 mm), manual ungual III (11 mm), manual claw sheaths, ilia (52 mm), partial pubis, incomplete ischium (~28 mm), incomplete femora (~84 mm), incomplete tibia, incomplete fibula, metatarsal I (9 mm), phalanx I-1 (6 mm), pedal ungual I (6 mm), distal metatarsal II, phalanx II-1 (12 mm), phalanx II-2 (9 mm), pedal ungual II (13 mm), distal metatarsal III, phalanx III-1 (17 mm), phalanx III-2 (13 mm), phalanx III-3, pedal ungual III, distal metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal claw sheaths, feathers
Diagnosis- (after Xu et al., 2011) maxillary posterior ramus has depth at mid-length exceeding that of dentary; surangular has little lateral exposure and forms a wide, flat dorsal surface over posterior part of mandible; extremely large surangular foramen >6% of mandibular length; posterior end of mandible blunt and dorsoventrally expanded; proximalmost caudal centra less than half as long as posterior dorsal centra; metacarpal III more robust than metacarpals I and II; manual phalanx II-2 longer than metacarpal II.
Comments- As the holotype was acquired from a dealer with no quarry information, Xiaotingia may instead be from the Yixian Formation which outcrops in the same area. Xu et al. (2011) used a version of Senter's TWG matrix to place Xiaotingia in Archaeopterygidae with Archaeopteryx and Anchiornis, with the family in basal Deinonychosauria. Most recently, Senter et al (2012) recovered Xiaotingia as a basal dromaeosaurid, Brusatte et al. (2014) as a basal troodontid, and Foth et al. (2014) and Lee et al. (2014) as a basal avialan. The taxon is thus relegated to Paraves incertae sedis here.
References- Xu, You, Du and Han, 2011. An Archaeopteryx-like theropod from China and the origin of Avialae. Nature. 475, 465-470.
Senter, Kirkland, DeBlieux, Madsen and Toth, 2012. New dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the evolution of the dromaeosaurid tail. PLoS ONE. 7(5), e36790.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.

Yixianosaurus Xu and Wang, 2003
Y. longimanus Xu and Wang, 2003
Late Valanginian-Early Aptian, Early Cretaceous
Lujiatun or Jianshangou Beds of the Yixian Formation, Liaoning, China
Holotype
- (IVPP V12638) (subadult or adult) (~1.3-2 kg) four partial dorsal ribs, seven gastralia or sternal ribs, furcula, scapulae (65 mm), coracoids, humeri (89 mm), radii (63 mm), ulnae (62, 64 mm), radiale, ulnare, semilunate carpal, metacarpal I (14.5 mm), phalanx I-1 (33, 34 mm), manual ungual I (26, 25 mm), metacarpal II (36, 35 mm), phalanx II-1 (26, 25 mm), phalanx II-2 (38, 36 mm), manual ungual II (28 mm), metacarpal III (34 mm), phalanx III-1 (~9 mm), phalanx III-2 (8 mm), phalanx III-3 (22 mm), manual ungual III (22.5, 23 mm), manual claw sheaths, fragments, feathers
Comments- This specimen was discovered in 2001 and described in 2003 as a maniraptoran perhaps most closely related to scansoriopterygids. This was based on the elongate manus (compared to humerus) and phalanx II-2 (compared to metacarpal II). These are correlated with each other however, as an elongate phalanx II-2 will lead to a long manus. In addition to scansoriopterygids, tyrannosauroids, ornithomimosaurs, troodontids, and some dromaeosaurids, basal avialans and basal coelurosaurs have similarly elongate II-2 (compared to II-1). Dececchi et al. (2010) restudied the specimen for an SVP abstract and while they were secretive regarding its phylogenetic position, do indicate it is not a paravian. Dececchi et al. (2012) later published a full paper, noting the presence of a furcula, and finding it to be a maniraptoran in a polytomy with alvarezsaurids, therizinosaurs and pennaraptorans. Xu et al. (2013) replied, describing misinterpretations of anatomy by Dececchi et al., including the supposed intermedium being a broken part of the semilunate carpal. They noted Dececchi et al. coded Yixianosaurus for many characters that could not be determined from the specimen, and their recoded matrix found it to be a deinonychosaur outside of Unenlagiinae, Eudromaeosauria and Troodontidae. Foth et al. (2014) recovered the genus as a basal paravian.
References- Xu and Wang, 2003. A new maniraptoran dinosaur from the Early Cretaceous Yixian Formation of Western Liaoning. Vertebrata PalAsiatica. 41(3), 195-202.
Dececchi, Hone, Sullivan and Xu, 2010. A re-analysis of the "coeluriasaurian pit-bull" Yixianosaurus longimanus with implications for the theropod dinosaur diversity of the Jehol Biota. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 81A.
Dececchi, Larsson and Hone, 2012. Yixianosaurus longimanus (Theropoda: Dinosauria) and its bearing on the evolution of Maniraptora and ecology of the Jehol fauna. Vertebrata PalAsiatica. 59(2), 111-139.
Xu, Sullivan and Wang, 2013. The systematic position of the enigmatic theropod dinosaur Yixianosaurus longimanus. Vertebrata PalAsiatica. 51(3), 169-183.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.

unnamed Paraves (Seeley, 1869)
Late Albian, Early Cretaceous
Cambridge Greensand, England

Material- ?(BGS 87931) (juvenile) first sacral vertebra (8.5 mm) (Galton and Martin, 2002b)
?(BGS 87933) proximal femur (Galton and Martin, 2002b)
(SMC B55274) dorsal vertebra (7.4 mm) (Seeley, 1869)
(SMC B55278) dorsal vertebra (10.1 mm) (Seeley, 1869)
(SMC B55280) dorsal vertebra (8.5 mm) (Seeley, 1869)
?(SMC B55328) proximal coracoid (Seeley, 1869)
(YORYMG 584) posterior cervical vertebra (9.3 mm) (Seeley, 1876)
Comments- SMC B55274, 55278 and 55280 are three of the four dorsal vertebrae listed as "Enaliornis" by Seeley (1869). SMC B55274 (mistyped B55279 in the figures of Galton and Martin, 2002b) and B55280 are dorsal vertebrae referred to Enaliornis sedgwicki by Seeley (1876), while YORYMG 584 was identified as an Enaliornis dorsal vertebra by Seeley. As they differ from hesperornithines, they were placed in Avialae incertae sedis by Galton and Martin (2002a, b) along with SMC B55278. Galton and Martin (2002b) tentatively referred the sacral vertebra BGS 87931 and proximal femur BGS 87933 to the same taxon. SMC B55328 was stated to be a proximal coracoid by Seeley (1869), and while possibly true, Galton and Martin (2002b) exclude it from Hesperornithes. This will be redescribed by Galton (in prep.). Galton et al. (2009) refer it all of this material to Aves indet..
References- Seeley, 1869. Index to the fossil remains of Aves, Ornithosauria and Reptilia, from the Secondary System of strata arranged in the Woodwardian Museum of the University of Cambridge. Deighton, Bell & Co., Cambridge. 143 pp.
Seeley, 1876. On the British fossil Cretaceous birds. Quarterly Journal of the Geological Society of London. 32, 496-515.
Galton and Martin, 2002a. Enaliornis, an Early Cretaceous hesperornithiform bird from England, with comments on other Hesperornithiformes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 317-338.
Galton and Martin, 2002b. Postcranial anatomy and systematics of Enaliornis Seeley, 1876, a footpropelled diving bird (Aves: Ornithurae: Hesperornithiformes) from the Early Cretaceous of England. Revue de Paleobiologie. 21(2), 489-538.
Galton, Dyke and Kurochkin, 2009. Re-analysis of Lower Cretaceous fossil birds from the UK reveals an unexpected diversity. Journal of Vertebrate Paleontology. 29(3), 102A.
Galton, in prep. Additional bird bones (Hesperornithiformes Enaliornis and Aves incertae sedis) from the Early Cretaceous of England. Revue Paleobiologie.

undescribed paravian (Lambe, 1902)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada

Material- (CMN coll.) proximal caudal vertebra
Comments- This was identified by Lambe (1902) as a posterior dorsal vertebra tentatively referred to Struthiomimus (his Ornithomimus altus) (plate XV figure 6-8), but is actually a caudal, and may be Troodon or Saurornitholestes based on its low square articular face.
Reference- Lambe, 1902. New genera and species from the Belly River Series (mid-Cretaceous). Geological Survey of Canada Contributions to Canadian Palaeontology. 3(2), 25-81.

undescribed paravian (Vidal, 1902)
Late Berriasian-Early Barremian, Early Cretaceous
La Pedrera de Rubies Lithographic Limestones Formation, Spain

Material- (destroyed) skeleton
Comments- Vidal (1902) mentioned the accidental destruction of a fossil bird, which based on provenence may belong to Noguerornis or the unnamed La Pedrera juvenile enantiornithine taxon.
Reference- Vidal, 1902. Sobre la presencia del tramo Kimeridgense del Montsech y hallazgo de un batracio en sus hiladas. Memorias de la Real Academia de Ciencias y Artes de Barcelona. 4(18), 263-267.

unnamed possible paravian (Zernezky, 1958)
Early Cretaceous
Tete-Oba, Ukraine
Material
- hindlimb (pedal digit III 50 mm)
Comments- Zernezky (1958) described this as a bird with narrow pedal digits and a very short hallux. He considered it to have ralliform affinities, but it has not been studied subsequently
Reference- Zernezky, 1958. Enigmatic imprint. Nature (Moscow). 4, 113, [in Russian]

undescribed Paraves (Nessov, 1977)
Early Cenomanian, Late Cretaceous
Khodzhakul Formation, Uzbekistan
Material
- teeth
Comments- Identified as Deinonychosauria by Nessov (1995).
References- Nessov, 1977. [Turtles and some other reptiles of the Cretaceous of Karakalpakia]. Voprosy gyerpyetology. Chyetvyertaya Vsyesoyuznaya Gyerpyetologichyeskaya konfyeryentsiya, Lyeningrad. Avtoryefyerat doklada. Lyeningrad, Nauka. 155-156.
Nessov, 1995. Dinosaurs of nothern Eurasia: new data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg. 1-156.

unnamed paravian (Jensen, 1981)
Late Kimmeridgian, Late Jurassic
Brushy Basin Member of the Morrison Formation, Colorado, US

Material- (BYUVP 2023) femur
Comments- This was first referred to Archaeopteryx by Jensen (1981), then to Theropoda indet. by Molnar (1985) and Maniraptora indet. by Jensen and Padian (1989). The large posterior trochanter indicates an assignment to either Avimimidae or Paraves, while the absence of a trochanteric crest excludes referral to Ornithurae (sensu Gauthier) or derived Troodontidae. The deeply separated anterior and greater trochanters are more similar to Avimimus, Unenlagia, Microraptor and Archaeopteryx, but unlike derived dromaeosaurids. The absent fourth trochanter eliminates Avimimus from consideration. It is here assigned to Paraves indet. pending further study. It may belong to "Paleopteryx", as the latter appears to be a microraptorian.
References- Jensen, 1981. [A new oldest bird?] Anima (Tokyo). 1981, 33-39. [in Japanese]
Jensen, 1981. Another look at Archaeopteryx as the worlds oldest bird. Encyclia, The Journal of the Utah Academy of Sciences, Arts, and Letters. 58, 109-128.
Molnar, 1985. Alternatives to Archaeopteryx; a survey of proposed early or ancestral birds. in Hecht, Ostrom, Viohl and Wellnhofer (eds). The Beginnings of Birds. Eichstatt, Germany: Freunde des Jura-Museums Eichstatt. 209-217.
Jensen and Padian, 1989. Small Pterosaurs and Dinosaurs from the Uncomphagre fauna (Brushy Basin Member, Morrison Formation: ?Tithonian), Late Jurassic, Western Colorado. Journal of Paleontology. 63(3), 364-373.
Padian, 1998. Pterosaurians and ?avians from the Morrison Formation (Upper Jurassic, Western U.S.). Modern Geology. 23, 57-68.

Paraves indet. (Kessler and Jurcsak, 1984)
Late Berriasian-Early Valanginian, Early Cretaceous
Cornet bauxite, Bihor, Romania

Material- (MTCO 17558; = MTCO-P 207; paratype of Limnornis corneti) proximal scapula
?(MTCO 17966) proximal radius
?(MTCO 17982) partial furcula
Comments- Kessler (1984) noted approximately sixty bird-like fragments from the Cornet bauxite, six of which can "with certainty be attributed to birds." These are the holotypes of Eurolimnornis corneti and Palaeocursornis corneti in addition to other isolated fragments, but most have been moved to Pterosauria or more generally Ornithodira and Archosauria indet. by Dyke et al. (2011) and Agnolin and Varricchio (2012).
MTCO 17558 was originally (Kessler and Jurcsak, 1984) decribed as a partial carpometacarpus and paratype of Limnornis corneti (later renamed Palaeocursornis corneti), and later (Kessler and Jurcsak, 1986) a paratype of Eurolimnornis corneti. Kurochkin (1995) used the carpometacarpus identification to argue for avian affinities of Eurolimnornis due to supposed distal fusion and tendinal sulcus, but Hope (2002) noted these are also present in Ichthyornis. Hope also noted it couldn't be referred definitively to Eurolimnornis or Palaeocursornis, and Dyke et al. reinterpreted it as a bird proximal scapula (though they probably mistakenly wrote it is not identifiable as a bird).
MTCO 17966 and 17982 were stated to be birds by Dyke et al., but that identity was doubted by Agnolin and Varricchio.
References- Kessler, 1984. Lower Cretaceous birds from Cornet, Roumania. In Rief and Westphal (eds). Third Symposium on Mesozoic Terrestrial Ecosystems, Tubingen. 119-121.
Kessler and Jurcsak, 1984. Fossil bird remains in the bauxite from Cornet (Romania, Bihor County). Travaux du Musee d'Histoire Naturelle, Grigore Antipa. 25, 393-401.
Kessler and Jurcsak, 1986. New contributions to the knowledge of the Lower Cretaceous bird remains from Cornet (Romania). Travaux du Musee d'Histoire Naturelle, Grigore Antipa. 28, 289-295.
Kurochkin, 1995. Synopsis of Mesozoic birds and early evolution of class Aves. Archaeopteryx. 13, 47-66.
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.
Dyke, Benton, Posmosanu and Naish, 2011. Early Cretaceous (Berriasian) birds and pterosaurs from the Cornet bauxite mine, Romania. Palaeontology. 54(1), 79-95.
Agnolin and Varricchio, 2012 . Systematic reinterpretation of Piksi barbarulna Varricchio, 2002 from the Two Medicine Formation (Upper Cretaceous) of Western USA (Montana) as a pterosaur rather than a bird. Geodiversitas. 34(4), 883-894.

unnamed paravian (Buffetaut, Marandat and Sige, 1986)
Late Cretaceous
Serviers, Gard, France
Material
- (Universite des Sciences et Techniques de Languedoc SER 03) partial tooth (~2.2 mm)
Comments- This tooth is relatively elongate and barely revurved. It has 14 distal serrations per mm, while the mesial serrations are indistinct. It was assigned to Dromaeosauridae by Buffetaut et al. (1986), but is most similar to supposed bird teeth from the Dinosaur Park Formation (Sankey et al., 2002) in its small size, tiny serrations, lack of much recurvature, and constricted base.
References- Buffetaut, Marandat and Sige, 1986. Decourvert de dents de Deinonychosaures (Saurischia, Theropoda) dans le Creace superieur du Sud de la France. Les Comptes rendus de l'Académie des sciences. 303, Serie II(15), 1393-1396.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

unnamed paravian (Buffetaut, Marandat and Sige, 1986)
Late Campanian-Early Maastrichtian, Late Cretaceous
Champ-Garimond, Gard, France
Material
- (Universite des Sciences et Techniques de Languedoc CHG 48) tooth (1.9 mm)
Comments- This tooth is short and slightly recurved, with a constricted base. There are 15 distal serrations per millimeter, while mesial serrations are only present as fine outlines. Like SER 03, it was assigned to Dromaeosauridae by Buffetaut et al. (1986), but is most similar to supposed bird teeth from the Dinosaur Park Formation (Sankey et al., 2002) in its small size, tiny serrations which are absent mesially, lack of much recurvature, and constricted base.
References- Buffetaut, Marandat and Sige, 1986. Decourvert de dents de Deinonychosaures (Saurischia, Theropoda) dans le Creace superieur du Sud de la France. Les Comptes rendus de l'Académie des sciences. 303, Serie II(15), 1393-1396.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

unnamed probable paravian (Weigert 1995)
Early Kimmeridgian, Late Jurassic
Alcobaca Formation, Portugal
Material
- (IPFUB GUI ARCH. 1) tooth
(IPFUB GUI ARCH. 3) tooth
(IPFUB GUI ARCH. 4) tooth
(IPFUB GUI ARCH. 5) tooth
(IPFUB GUI ARCH. 7) tooth
(IPFUB GUI ARCH. coll.) 98 teeth (1-2.6 mm)
Comments- These teeth are constricted basally, with mesial and distal carinae. Both lingual and labial surfaces are generally smooth, and the lingual surface is concave apically. The labial surface sometimes has faint grooves, which were believed to be from wear. Eighty-six teeth have both mesial and distal serrations, while the other seventeen sometimes lack mesial serrations and have carinae shifted lingually, so are probably premaxillary teeth. The teeth average 1.65 mm in crown height and .60 mm in FABL. Serrations are low and rounded or slightly pointed, with a miniscule size of 24/mm.
The specimens differ from Archaeopteryx and most definite avialans in having serrations. Weigert (1995) states these may be present but hidden in the former genus, since most Archaeopteryx teeth are only visible in labial view, where the serrations cannot be seen in the Guimarota specimens. Yet the London and Munich specimens of Archaeopteryx both expose serrationless teeth in lingual view, showing Weigert is incorrect. He explained the absence of serrations in the Munich specimen by claiming it was a distinct species (A. bavarica) which may have differed from A. lithographica in this respect, but this is special pleading, and the distinctness of A. bavarica is very poorly supported (see discussion in Archaeopteryx entry). The diagonally oriented carina on the apical half of the tooth is described as an archaeopterygiform apomorphy, but this is true of any teeth which share the same stout, highly recurved outline (e.g. Sinornithoides). The other cited archaeopterygiform apomorphy is the lingually projected mesial carina, but this is found in other taxa such as Sinornithosaurus' anterior teeth. The teeth do seem to be maniraptoriform, based on the constricted crown base, and are not referrable to several groups due to their serrations (Ornithomimosauria, Parvicursorinae, Oviraptorosauria, Avialae), but also lack the enlarged serrations found in most therizinosaurs and derived troodontids. They may belong to a basal troodontid or dromaeosaurid, but are not archaeopterygid.
Reference- Weigert, 1995. Isolierte Zahne von cf. Archaeopteryx sp. aus dem Oberen Jura der Kohlengrube Guimarota (Portugal). N. Jb., Geol. Palaont. Mh. 9, 562-576.

undescribed Paraves (Kirkland et al., 1997)
Late Albian, Early Cretaceous
Mussentuchit Member of the Cedar Mountain Formation, Utah, US

Material- teeth
Comments- Kirkland et al. (1997) listed Aves order indet., while Cifelli et al. (1999) noted two Avialae dental morphs, one referrable to Hesperornithes and one not.
References- Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
Cifelli, Nydam, Gardner, Weil, Eaton, Kirkland, Madsen, 1999. Medial Cretaceous vertebrates from the Cedar Mountain Formation, Emery County, Utah: the Mussentuchit Local Fauna. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 219-242.

undescribed Paraves (Tokaryk, Cumbaa and Storer, 1997)
Middle Cenomanian, Late Cretaceous
Belle Fourche Member of the Ashville Formation, Saskatchewan, Canada

Material- (SMNH coll.) four fused synsacral vertebrae, several coracoids, proximal carpometacarpus, three pelvic elements, many fragments (Tokaryk et al., 1997)
many elements (Cumbaa et al., 2006)
Comments- Tokaryk et al. (1997) note many unidentified bird elements, including three pelvic elements which may belong to Pasquiaornis. Cumbaa et al. (2006) mention numerous bird remains from the Bainbridge River Bonebed, some of which are probably not Pasquiaornis.
References- Tokaryk, Cumbaa and Storer, 1997. Early Late Cretaceous birds from Saskatchewan, Canada: the oldest diverse avifauna known from North America. Journal of Vertebrate Paleontology. 17(1), 172-176.
Cumbaa, Schröder-Adams, Day and Phillips, 2006. Cenomanian bonebed faunas from the northeastern margin, Western Interior Seaway. In Lucas and Sullivan (eds). Late Cretaceous Vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin. 35, 139-155.

unnamed paravian (Rodriguez de la Rosa and Cevallos-Ferriz, 1998)
Late Campanian, Late Cretaceous
Cerro del Pueblo Formation, Mexico
Material
- (IGM-7711) pedal phalanx II-I (18.8 mm)
(IGM-7712) pedal phalanx II-2 (21.7 mm)
Comments- These may belong to the same individual, which was tentatively referred to Troodontidae by Rodriguez de la Rosa and Cevallos-Ferriz (1998) based on the centrally placed collateral ligament pit, which is also found in Saurornithoides and Troodon. However, the slightly longer II-2 compared to II-1 is more similar to dromaeosaurids. It is from a different taxon than IGM-7710 as it is not nearly as elongate, and different from IGM-7715 as it has a centrally placed collateral ligament pit.
Reference- Rodriguez de la Rosa and Cevallos-Ferriz, 1998. Vertebrates of the El Pelillal locality (Campanian, Cerro del Pueblo Formation), Southeastern Coahuila, Mexico. Journal of Vertebrate Paleontology. 18, 751-764.

unnamed paravian (Rodriguez de la Rosa and Cevallos-Ferriz, 1998)
Late Campanian, Late Cretaceous
Cerro del Pueblo Formation, Mexico
Material
- (IGM-7715) distal pedal phalanx II-2
Comments- This was tentatively referred to Dromaeosauridae by Rodriguez de la Rosa and Cevallos-Ferriz (1998) based on the dorsally placed collateral ligament pit. However, this character is also present in basal troodontids (e.g. IGM 100/44, Sinornithoides, Borogovia), Neuquenraptor and Rahonavis. It is a different taxon than IGM-7710 and IGM-7712, both of which have centrally placed collateral ligement pits.
Reference- Rodriguez de la Rosa and Cevallos-Ferriz, 1998. Vertebrates of the El Pelillal locality (Campanian, Cerro del Pueblo Formation), Southeastern Coahuila, Mexico. Journal of Vertebrate Paleontology. 18, 751-764.

unnamed possible paravian (Molnar, 1999)
Albian, Early Cretaceous
Griman Creek Formation, New South Wales, Australia
Material
- (AM F103590) proximal tibiotarsus (5.9x4.6 mm)
Comments- This specimen is less derived than ornithuromorphs except for Patagopteryx in lacking a medial cnemial crest. The proximal surface is not round, unlike most enantiornithines. Molnar excluded non-bird theropods based on the lack of cnemial crest curvature and poorly developed condyles. Unfortunately, good comparative material for basal birds is lacking.
Reference- Molnar, 1999. Avian tibiotarsi from the Early Cretaceous of Lightning Ridge, N.S.W. In Tomida, Rich and Rich (eds). Proceedings of the Second Gondwanan Dinosaur Symposium, National Sciences Museum Monographs. 15, 197-209.

unnamed Paraves (Forster and O'Connor, 2000)
Middle Maastrichtian, Late Cretaceous
Anembalemba Member of Maevarano Formation, Madagascar
Material
- (FMNH PA 749; Humeral Taxon F) incomplete humerus (~19 mm) (O'Connor and Forster, 2010)
(FMNH PA 751) proximal radius (O'Connor and Forster, 2010)
(UA 9610) incomplete metatarsal I (O'Connor and Forster, 2010)
(UA 9611) incomplete metatarsal I (O'Connor and Forster, 2010)
Comments- Forster and O'Connor (2000) reported a bird dentary, though this has not been mentioned in subsequent publications and has since been reidentified (O'Connor, pers. comm. 2014). The humerus FMNH PA 749 was assigned to Avialae indet. by O'Connor and Forster (2010). The latter authors do not assign the radius or metatarsals I to a taxon more exact than Avialae, though they do state the metatarsals lack the enantiornithine J-shape.
References- Forster and O'Connor, 2000. The avifauna of the Upper Cretaceous Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 20(3), 41A-42A.
O'Connor and Forster, 2010. A Late Cretaceous (Maastrichtian) avifauna from the Maevarano Formation, Madagascar. Journal of Vertebrate Paleontology. 30(4), 1178-1201.

undescribed probable paravian (Norton, DML 2000)
Late Campanian, Late Cretaceous
Djadochta Formation, Mongolia

Material- (IGM 97/155)
Comments- Norton (DML, 2000) noted this specimen was on display at the AMNH Fighting Dinosaurs exhibit. Discovered in 1997 at Ukhaa Tolgod, it is said to be unpublished but exhibit "raptor-like" traits.
Reference- http://dml.cmnh.org/2000Jun/msg00082.html

Paraves indet. (Sankey and Brinkman, 2000)
Late Campanian, Late Cretaceous
Judith River Group, Alberta, Canada
Material
- ?(RTMP 84.92.205) tooth (2.7 mm) (Sankey et al., 2002)
?(RTMP 86.21.68) tooth (3.7 mm) (Sankey et al., 2002)
(RTMP 86.45.27) tooth (3.7 mm) (Sankey et al., 2002)
(RTMP 86.52.54) tooth (4.7 mm) (Sankey et al., 2002)
(RTMP 86.172.53) tooth (2.9 mm) (Sankey et al., 2002)
(RTMP 87.4.19) tooth (5.5 mm) (Sankey et al., 2002)
(RTMP 87.4.46) tooth (3.6 mm) (Sankey et al., 2002)
(RTMP 87.20.8) tooth (4.3 mm) (Sankey et al., 2002)
(RTMP 87.30.10) tooth (~3.7 mm) (Sankey et al., 2002)
?(RTMP 87.158.76) tooth (3.3 mm) (Sankey et al., 2002)
(RTMP 87.158.77) tooth (3.1 mm) (Sankey et al., 2002)
(RTMP 88.11.65) tooth (2.9 mm) (Sankey et al., 2002)
?(RTMP 89.103.25) tooth (5.4 mm) (Sankey et al., 2002)
(RTMP 95.145.34a) tooth (2.1 mm) (Sankey et al., 2002)
(RTMP 95.145.34b) tooth (4 mm) (Sankey et al., 2002)
(RTMP 95.145.34c) tooth (3.5 mm) (Sankey et al., 2002)
(RTMP 95.147.30) tooth (2.4 mm) (Sankey et al., 2002)
(RTMP 95.151.21) tooth (2.3 mm) (Sankey et al., 2002)
?(RTMP 95.174.52) tooth (2.3 mm) (Sankey et al., 2002)
?(RTMP 95.177.79) tooth (3 mm) (Sankey et al., 2002)
(RTMP 95.180.49) tooth (3.2 mm) (Sankey et al., 2002)
(RTMP 95.181.10a) tooth (3.1 mm) (Sankey et al., 2002)
(RTMP 95.181.10b) tooth (3.3 mm) (Sankey et al., 2002)
?(RTMP 95.181.10c) tooth (3.3 mm) (Sankey et al., 2002)
(RTMP 95.181.10d) tooth (3.3 mm) (Sankey et al., 2002)
?(RTMP 95.181.60e) tooth (2.4 mm) (Sankey et al., 2002)
?(RTMP 95.181.60f) tooth (2.5 mm) (Sankey et al., 2002)
(RTMP 96.62.51) tooth (3.2 mm) (Sankey et al., 2002)
(RTMP 96.62.62) tooth (3.5 mm) (Sankey et al., 2002)
(RTMP 96.62.62a) tooth (3.8 mm) (Sankey et al., 2002)
(RTMP 96.62.62b) tooth (2.7 mm) (Sankey et al., 2002)
Comments- These teeth are said to resemble Hesperornis, and may belong to hesperornithines and/or enantiornithines. Several are questionably referred to birds (indicated by question marks above), since they have serrations (generally very tiny), which are unreported in bird teeth preserved in situ (except Longipteryx). They may belong to juvenile Richardoestesia instead, which the bird teeth grade into.
References- Sankey and Brinkman, 2000. New theropod and bird teeth from the Late Cretaceous (Campanian) Judith River Group, Alberta. Journal of Vertebrate Paleontology. 20(3), 67A.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

undescribed possible paravian (Unwin and Matsuoka, 2000)
Valanginian-Hauterivian, Early Cretaceous
Kuwajima Formation of the Tetori Group, Japan
Material
- (SBEI 1221) posterior mandible
Comments- This was figured by Unwin and Matsuoka (2000) as an "avian? right articular."
Reference- Unwin and Matsuoka, 2000. Pterosaurs and birds. In Matsuoka (ed.). Fossils of the Kuwojima "Kasekikabe" (Fossil-bluff): Scientific report on a Neocomian (Early Cretaceous) fossil assembrage from the Kuwajima Formation, Tetori Group, Shiramine, Ishikawa, Japan. Shiramine Village Board of Education, Ishikawa. 99-104.

undescribed paravian (Bertini, Santucci and Arruda-Campos, 2001)
Late Maastrichtian, Late Cretaceous
Echapora Member of the Marilia Formation of the Bauru Group, Brazil
Material
- (MPMA-73) tooth
Comments- This was listed as a deinonychosaur tooth, but has not yet been illustrated or described.
Reference- Bertini, Santucci and Arruda-Campos, 2001. Titanossauros (Sauropoda: Saurischia) no Cretaceo Superior continental (Formaceo Marilia, Membro Echapora) de Monte Alto, Estado de São Paulo, e correlacao com formas associadas no Triangulo Mineiro. Geociencias, Sao Paulo. 20(1/2), 93-103.

undescribed possible paravian (Amiot, Buffetaut, Tong, Boudad and Kabiri, 2002)
Cenomanian, Late Cretaceous
Kem Kem beds, Morocco
Material
- (M-ZA-017) tooth (14 mm) (Amiot, Buffetaut, Tong, Boudad and Kabiri, 2004)
Comments- This tooth is straight and short, with a BW/FABL of 0.6. The lingual side is concave, and the labial side convex. Both carinae have serrations which are apically inclined and lie on the midline. Mesial serrations (2/mm) and dista1 serrations (2.1/mm) are both large, with shallow interdenticle pits.
Amiot et al. (2002) first referred this specimen to Troodontidae based on the lens-shaped cross section, low DSDI, and large serrations which are apically inclined. They later (2004) referred it to Dromaeosauridae, as Currie said the base was too narrow and the serrations resembled dromaeosaurids.
References- Amiot, Buffetaut, Tong, Boudad and Kabiri, 2002. Laurasian theropod dinosaur teeth from the Late Cretaceous of Morocco. Conference abstract, Third Georges Cuvier Symposium, Montbeliard, France.
Amiot, Buffetaut, Tong, Boudad and Kabiri, 2004. Isolated theropod teeth from the Cenomanian of Morocco and their palaeobiogeographical significance. Revue de Paleobiologie, Geneve. 9, 143-149.

unnamed Paraves (Franco-Rosas, 2002)
Turonian-Late Maastrichtian, Late Cretaceous
Adamantina and Marilia Formations of the Bauru Group, Brazil

Material- teeth
Description- These teeth have long serrations with varied slopes and distal shapes, and slightly pronounced interdenticle slits. They are said to be similar to troodontids and velociraptorines.
Reference- Franco-Rosas, 2002. Methodological parameters for the identification and taxonomic classification of isolated theropodomorph teeth. Anais da Academia Brasileira de Ciencias. 74(2), 367.

unnamed possible paravian (Riff, Kellner, Mader and Russell, 2002)
Cenomanian, Late Cretaceous
Kem Kem beds, Morocco

Material- (CMN 50852) incomplete dorsal vertebra (21 mm)
Comments- Riff et al. (2002, 2004) considered this most similar to Rahonavis, though it differs in being more elongate, having a larger neural canal and lacking pleurocoels or lateral fossae. Chiarenza and Cau (2016) stated the specimen lacked unambiguous paravian or avialan characters, noting in particular the large neural canal is present in many small theropods and crocodyliforms.
References- Riff, Kellner, Mader and Russell, 2002. On the occurence of an avian vertebra in Cretaceous strata of Morocco, Africa. Anais da Academia Brasileira de Ciencias. 74(2), 367-368.
Riff, Mader, Kellner and Russell, 2004. An avian vertebra from the continental Cretaceous of Morocco, Africa. Arquivos do Museu Nacional. 62(2), 217-223.
Chiarenza and Cau, 2016. A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments on the Cenomanian theropods from North Africa. PeerJ. 4:e1754.

unnamed probable Paraves (Sankey, Brinkman, Guenther and Currie, 2002)
Late Campanian, Late Cretaceous
Dinosaur Park Formation of the Judith River Group, Alberta, Canada

Material- (RTMP 84.92.205) tooth (2.7 mm)
(RTMP 86.21.68) tooth (3.7 mm)
(RTMP 86.45.27) tooth (3.7 mm)
(RTMP 86.52.54) tooth (4.7 mm)
(RTMP 86.172.53) tooth (2.9 mm)
(RTMP 87.4.19) tooth (5.5 mm)
(RTMP 87.4.46) tooth (3.6 mm)
(RTMP 87.20.8) tooth (4.3 mm)
(RTMP 87.30.10) tooth (~3.7 mm)
(RTMP 87.158.76) tooth (3.3 mm)
(RTMP 87.158.77) tooth (3.1 mm)
(RTMP 88.11.65) tooth (2.9 mm)
(RTMP 89.103.25) tooth (5.4 mm)
(RTMP 95.145.34a) tooth (2.1 mm)
(RTMP 95.145.34b) tooth (4 mm)
(RTMP 95.145.34c) tooth (3.5 mm)
(RTMP 95.147.30) tooth (2.4 mm)
(RTMP 95.151.21) tooth (2.3 mm)
(RTMP 95.174.52) tooth (2.3 mm)
(RTMP 95.177.79) tooth (3 mm)
(RTMP 95.180.49) tooth (3.2 mm)
(RTMP 95.181.10a) tooth (3.1 mm)
(RTMP 95.181.10b) tooth (3.3 mm)
(RTMP 95.181.10c) tooth (3.3 mm)
(RTMP 95.181.10d) tooth (3.3 mm)
(RTMP 95.181.60e) tooth (2.4 mm)
(RTMP 95.181.60f) tooth (2.5 mm)
(RTMP 96.62.51) tooth (3.2 mm)
(RTMP 96.62.62) tooth (3.5 mm)
(RTMP 96.62.62a) tooth (3.8 mm)
(RTMP 96.62.62b) tooth (2.7 mm)
Comments- These teeth are distinguished from other Dinosaur Park theropods by their small size, constricted bases, slight recurvature, and general absence of serrations. Distal serrations are present in about a fourth of the sample and are tiny (>8/mm), while minute mesial serrations are only present in one tooth (RTMP 89.103.25). About half have distinct carinae. Some resemble Mononykus except for their concave distal edge. Others most closely resemble hesperornithines, as noted by Sankey et al. (2002). Those authors referred the teeth to Aves indet., but also noted Microraptor has similar teeth. However, neither alvarezsaurids nor ornithurines (sensu Gauthier; except for Longipteryx) have been reported to have serrations. Microraptor has highly heterodont dentition where the anterior serrationless teeth are more recurved and lack a basal constriction, while the posterior teeth are similar except in having slightly larger serrations (8/mm).
Reference- Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

undescribed paravian (Poblete and Calvo, 2003)
Late Turonian-Early Coniacian, Late Cretaceous
Portezuelo Formation of Rio Neuquen Group, Neuquen, Argentina

Material- teeth
Description- These are labiolingually compressed teeth with strongly posteriorly inclined crowns which are sometimes proportionally short. They lack mesial serrations but have distal ones. A labial carina is present, continuing apically to the tip of the distal side. It sometimes has small serrations.
Comments- It's possible they are referrable to Unenlagia? paynemili from the same quarry, though the unenlagiines Austroraptor and Buitreraptor lack serrations completely.
Reference- Poblete and Calvo, 2003. Upper Turonian dromaeosaurid teeth from Futalognko quarry, Barreales Lake, Neuquén, Patagonia, Argentina. Ameghiniana. 40(S), 66R.

unnamed Paraves (Osi, 2004)
Santonian, Late Cretaceous
Csehbanya Formation, Hungary

Material- (MTM V.2002.05) (juvenile) distal femur
(MTM V.2003.19) distal metatarsal III
Comments- These were briefly described as enantiornithines by Osi (2004), but later placed more generally as non-avian birds by him in 2008 when they were described in detail.
References- Osi, 2004. Enantiornithine bird remains from the Late Cretaceous of Hungary. Sixth International Meeting of the Society of Avian Palaeontology and Evolution, Abstracts. 50.
Osi, 2008. Enantiornithine bird remains from the Late Cretaceous of Hungary. Oryctos. 7, 55-60.

undescribed Paraves (Ikejiri, Watkins and Gray, 2006)
Late Kimmeridgian, Late Jurassic
Brushy Basin Member of the Morrison Formation, Wyoming, US
Material
- (WDC BS-641) tooth
(WDC BS-885) tooth
(WDC BS-889) tooth
Reference- Ikejiri, Watkins and Gray, 2006. Stratigraphy, sedimentology, and taphonomy of a sauropod quarry from the Upper Jurassic Morrison Formation of Themopolis, central Wyoming. in Foster and Lucas (eds.). New Mexico Museum of Natural History Bulletin. 36, 36-46.

undescribed paravian (Naish, Martill and Merrick, 2007)
Late Aptian, Early Cretaceous
Nova Olinda Member of the Crato Formation, Brazil
Material
- (Senckenberg Museum coll.) carpals, three remiges (14, 81 mm)
Comments- Naish et al. (2007) discuss this as bird remains, but as e.g. Microraptor has asymmetrical feathers too, it may be from another kind of paravian.
Reference- Naish, Martill and Merrick, 2007. Birds of the Crato Formation. In: Martill, Bechly and Loveridge (eds.). The Crato fossil beds of Brazil: Window into an ancient world. Cambridge University Press. 525-533.

undescribed paravian (Parsons and Parsons, 2007)
Late Aptian, Early Cretaceous
Cloverly Formation, Montana

Material- (MCZ or MOR coll. in part) manual phalanx
Comments- This and possibly referrable fragments were found as gut contents in a Deinonychus specimen, either MCZ 8791 or MOR 1178.
Reference- Parsons and Parsons, 2007. Avian-like manual phalanx found within gut contents of Lower Cretaceous dromaeosaurid: New data on the feeding behavior of Deinonychus antirrhopus (Saurischia: Theropoda). Journal of Vertebrate Paleontology. 27(3), 128A.

undescribed paravian (Tykoski and Fiorillo, 2007)
Middle Cenomanian, Late Cretaceous
Woodbine Formation, Texas, US
Material
- scapula, manual phalanx II-1, partial limb element, fragments
Reference- Tykoski and Fiorillo, 2007. Avian remains and other vertebrates from a new locality in the Woodbine Formation (Middle Cenomanian) of north-central Texas. Journal of Vertebrate Paleontology. 27(3), 161A.

undescribed paravian (Close and Vickers-Rich, 2009)
Aptian, Early Cretaceous
Wonthoggi Formation of the Strzelecki Group, Victoria, Australia
Material
- ulna
Reference- Close and Vickers-Rich, 2009. Australia's Mesozoic birds: New material from the Early Cretaceous of Victoria. Journal of Vertebrate Paleontology. 29(3), 80A.

unnamed paravian (Fanti and Miyashita, 2009)
Late Campanian, Late Cretaceous
Wapiti Formation, Alberta, Canada

Material- (RTMP 2004.93.4) tooth
Comments- This was referred to a bird by Fanti and Miyashita (2009).
Reference- Fanti and Miyashita, 2009. A high latitude vertebrate fossil assemblage from the Late Cretaceous of west-central Alberta, Canada: Evidence for dinosaur nesting and vertebrate latitudinal gradient. Palaeogeography, Palaeoclimatology, Palaeoecology. 275, 37-53.

unnamed Paraves (Larson, Brinkman and Bell, 2010)
Early Maastrichtian, Late Cretaceous
Horseshoe Canyon Formation, Alberta, Canada

Material- (RTMP 2000.45.52) tooth (Larson, Brinkman and Bell, 2010)
(RTMP 2000.45.57) tooth (Larson, Brinkman and Bell, 2010)
(RTMP 2003.57.2) tooth (Larson, Brinkman and Bell, 2010)
(RTMP or UALVP coll.) quadrate (Eberth and Currie, 2010)
two teeth (Larson, Brinkman and Bell, 2010)
References- Eberth and Currie, 2010. Stratigraphy, sedimentology, and taphonomy of the Albertosaurus bonebed (upper Horseshoe Canyon Formation; Maastrichtian), southern Alberta, Canada. Canadian Journal of Earth Sciences. 47(9), 1119-1143.
Larson, Brinkman and Bell, 2010. Faunal assemblages from the upper Horseshoe Canyon Formation, an early Maastrichtian cool-climate assemblage from Alberta, with special reference to the Albertosaurus sarcophagus bonebed. Canadian Journal of Earth Sciences. 47(9), 1159-1181.

unnamed paravian (Delcourt and Grillo, 2014)
Campanian-Maastrichtian, Late Cretaceous
Vale do Rio do Peixe Formation, Brazil
Material
- (DGM 930-R) (~3 m; ~40 kg) partial dorsal rib, several dorsal rib fragments, partial proximal caudal vertebra (42 mm), incomplete mid caudal centrum (~41 mm), ?ischial fragment, femoral fragment (~273 mm), partial pedal ungual ?I/IV, fragments
Comments- Delcourt and Grillo (2014) referred this specimen to Maniraptora (but not Oviraptorosauria or Alvarezsauridae), and tentatively to Deinonychosauria.
Reference- Delcourt and Grillo, 2014. On maniraptoran material (Dinosauria: Theropoda) from Vale do Rio do Peixe Formation, Bauru Group, Brazil. Revista Brasileira de Paleontologia. 17(3), 307-316.

undescribed possible Paraves (Gallina, Apesteguia, Haluza and Canale, 2014)
Late Berriasian-Valanginian, Early Cretaceous
Bajada Colorada Formation, Neuquen, Argentina
Comments
- Gallina et al. (2014) mentioned possible deinonychosaurs from this formation.
Reference- Gallina, Apesteguia, Haluza and Canale, 2014. A diplodocid sauropod survivor from the Early Cretaceous of South America. PLoS ONE. 9(5), e97128.

unnamed Paraves (Lefevre, Cau, Hu, Wu, Escuillie and Godefroit, 2014)
Oxfordian, Late Jurassic
Tiaojishan Formation, Liaoning, China

Material- (YFGP-T5199) (juvenile or subadult) skeleton
(YFGP-T5200) skeleton
(YFGP-T5201) skeleton
Comments- These were asigned to Avialae by Lefevre et al. (2014). Given other supposed Tiaojishan basal avialans have been assigned to Troodontidae, Dromaeosauridae, or basal Paraves in various analyses, they are only assigned to Paraves here. Some may end up being specimens of Anchiornis, Aurornis, Eosinopteryx or Xiaotingia.
YFGP-T5199 is said to have symmetrical remiges, and stage 1 feathers on the tail and hindlimbs. YFGP-T5200 is stated to have retrices and T5201 has several troodontid-like cranial characters.
Reference- Lefevre, Cau, Hu, Wu, Escuillie and Godefroit, 2014. New basal Avialae from the Jurassic of China. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 167.

undescribed paravian (Fortner, 2015)
Early Maastrichtian, Late Cretaceous
Aguja Formation, Texas, US

Material- partial postcranial skeleton
Comments- This was said to be "compatible with identification as either Troodontidae or Dromaeosauridae." It may be Richardoestesia or Paronychodon, if not a eudromaeosaur or troodontine.
Reference- Fortner, 2015. A small theropod dinosaur from the Aguja Formation (Upper Cretaceous), Big Bend National Park, Texas. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 126.

unnamed paravian (Gates, Zanno and Makovicky, 2015)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, South Dakota, US
Material
- (FMNH PR2900) tooth (4.4x2.2x1 mm)
Reference- Gates, Zanno and Makovicky, 2015. Theropod teeth from the upper Maastrichtian Hell Creek Formation "Sue" Quarry: New morphotypes and faunal comparisons. Acta Palaeontologica Polonica. 60(1), 131-139.

undescribed Paraves (Mohr and Currie, 2015)
Early Campanian, Late Cretaceous
Milk River Formation, Alberta, Canada
Material
- teeth
Reference- Mohr and Currie, 2015. The development of bird teeth from the Late Cretaceous of Alberta. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 182.

undescribed Paraves (Mohr and Currie, 2015)
Late Campanian, Late Cretaceous
Dinosaur Park Formation, Alberta, Canada
Material
- teeth
Reference- Mohr and Currie, 2015. The development of bird teeth from the Late Cretaceous of Alberta. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 182.

undescribed ornithine (Rivera-Sylva, Frey, Stinnesbeck, Padilla Gutierrez, Gonzalez Gonzalez and Amezcua Torres, 2015)
Late Campanian, Late Cretaceous
Cerro del Pueblo Formation, Mexico

Reference- Rivera-Sylva, Frey, Stinnesbeck, Padilla Gutierrez, Gonzalez Gonzalez and Amezcua Torres, 2015. The Late Cretaceous Las Aguilas dinosaur graveyard, Coahuila, Mexico. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 203.

Archaeopterygidae Huxley, 1871
Definition- (Archaeopteryx lithographica <- Dromaeosaurus albertensis, Passer domesticus) (Xu, You, Du and Han, 2011)
= Sauriurae Haeckel, 1866
= Saururae Huxley, 1867
= "Archornithidae" Carus, 1875
= Saurornithes Nicholson, 1878a/b
Definition- (Archaeopteryx lithographica <- Passer domesticus) (Martyniuk, 2012)
= Saururi Vogt, 1879
= Ornithopappi Stejneger, 1885
= Archaeopteryges Furbringer, 1888
= Archaeopterygiformes Furbringer, 1888
= Archornithes Furbringer, 1888
= Saurura Steinmann and Doederlein, 1890
= Archornithiformes Shefeldt, 1903
= Archaeornithidae Petronievics, 1925
= Archaeopterygomorphi Hay, 1930
= Archaeopteryx sensu Sereno, 1998
Definition- (Archaeopteryx lithographica <- Passer domesticus) (modified)
= Archaeopterygidae sensu Sereno, in press
Defrinition- (Archaeopteryx lithographica <- Passer domesticus)
Ex-archaeopterygids- Several taxa have been referred to Archaeopterygidae or Archaeopteryx itself in the past, but do not belong there. Janensch (1914) first noted an Archaeopteryx-like supposed carpometacarpus (HMN coll.) from the Tendaguru Formation of Tanzania, but this is based on a misreading of Stremme (1916-1919), who was describing differences from Archaeopteryx. This was named Stremmeia by Nopcsa (1930) and reidentified as a salientian tibiofibulare, and while this identification has been doubted by late twentieth century authors, the specimen is also highly dissimilar to maniraptoran elements. Lambrecht (1933) noted a specimen labeled Archaeopteryx "vicensensis" at the Museum zu Vicensa, but found it was a pterosaur after writing Kleinschmidt. Jensen (1981) identified a proximal femur (BYU 2023) from the Morrison Formation as Archaeopteryx, but it is also similar to basal dromaeosaurids such as Microraptor and Unenlagia so is placed as Paraves incertse sedis here. Kessler and Jurcsak (1984) described an incomplete supposed humerus from the Early Cretaceous of Romania as Archaeopteryx sp., but this was reidentified by Dyke et al. (2011) as a long bone of Archosauria indet.. Paul (1988) referred all dromaeosaurids to Archaeopterygidae, which has not been recovered in any phylogenetic analysis. "Proornis" was originally called "the North Korean Archaeopteryx" (e.g. Anonymous, 1994), but is actually a confuciusornithid (Gao et al., 2009). Weigert (1995) described 103 teeth from the Guimarota Formation of Portugal as cf. Archaeopteryx sp., but they are not avialan and may belong to a basal deinonychosaur instead. Protarchaeopteryx was assigned to the family by Ji and Ji (1997) and Paul (2002), but is a basal oviraptorosaur. Forster et al. (1998) found Rahonavis and Unenlagia to clade with Archaeopteryx in some most parsimonious trees, but Rahonavis has generally been found to be an ornithurine or dromaeosaurid since, while Unenlagia has been found in basal Avialae or Dromaeosauridae. Rauhut (2002) referred Paronychodon to Archaeopterygidae, but this was based on comparisons to the Guimarota teeth noted above and the genus is here assigned to Troodontidae based on enamel microstructure. Ji et al. (2005) described Jinfengopteryx as being more closely related to Archaeopteryx than to Aves, but is now recognized as a basal troodontid or basal paravian. Xu et al. (2011) recently used a version of Senter's TWG analysis to refer Xiaotingia to Archaeopterygidae, but the genus has also been placed as a basal troodontid and basal dromaeosaurid.
Sauriurae- Sauriurae was a group first used by Haekel (1866) for Archaeopteryx, who placed Neornithes/Aves in the Ornithurae instead. This taxonomy was followed for over a century, with hesperornithines and ichthyornithines being added to Ornithurae by later authors. Martin (1983) was the first author to place enantiornithines in Sauriurae, which has been followed near universally by those who doubt the dinosaur-bird relationship. Additional taxa have also been assigned to Sauriurae including Confuciusornis (Hou et al., 1995), Sinosauropteryx (Ji and Ji, 1996), Protarchaeopteryx (Ji and Ji, 1997), Yandangornis (Cai and Zhao, 1999), Caudipteryx (Martin and Czerkas, 2000), Jeholornis (Martin, 2004), Vorona (Kurochkin, 2006), and lately all deinonychosaurs and oviraptorosaurs (Martin, 2004). The group has basically consisted of any non-ornithuromorph birds considered by the authors, with the notable exception of Kurochkin (2006), who places Protoavis and confuciusornithids in Ornithurae and views sauriurines as being theropods while ornithurines are not. While there may be some evidence for placing confuciusornithids and enantiornithines in a group exclusive of Aves, phylogenetic analyses are unanimous in rejecting a clade of Archaeopteryx and enantiornithines which excludes Aves.
References- Haekel, 1866. Generelle Morphologie der Organismen: allgemeine Grundzüge der organischen Formen-Wissenschaft, mechanisch begründet durch die von Charles Darwin reformirte Descendenz-Theorie. Berlin: Reimer. 462 pp.
Huxley, 1867. On the classification of birds; and on the taxonomic value of the modifications of certain of the cranial bones observable in that class. Proceedings of the Zoological Society of London. 35, 415-472.
Carus, 1875. Handbuch der Zoologie. Erster Band: Wirbelthiere, Mollusken und Molluskoiden. 894 pp.
Nicholson, 1878a. A Manual of Zoology for the Use of Students with a General Introduction on the Principles of Zoology. Blackwood and Sons: Edinburgh and London. 800 pp.
Nicholson, 1878b. Advanced Text-Book of Zoology for Junior Students. Blackwood and Sons: Edinburgh and London. 405 pp.
Vogt, 1879. L'Archaeopteryx macroura, Un intermediaire entre les oiseaux et les reptiles. La Revue Scientifique. 9(2), 241-248.
Stejneger, 1884. Classification of Birds. Science Record. 2(7), 154-155.
Furbringer, 1888. Untersuchungeb zur Morphologie und Systematik der Vogel. Amsterdam: Holkema. 1751 pp.
Steinmann and Doederlein, 1890. Elemente der paläontologie bearbeitet. Leipzig. 848 pp.
Shufeldt, 1903. On the classification of certain groups of birds. The American Naturalist. 37, 33-64.
Janensch, 1914. Ubersicht uber die Wirbeltierfauna der Tendaguru-Schichten. Archiv fur Biontologie. 3, 81-110.
Stremme, 1916-1919. Uber die durch Bandverknocherung hervorgerufene proximale Verschmelzung zweier Mittelhand - oder Mittelfussknochen eines Reptils. Wissenschaftliche Ergebnisse der Tendaguru-Expedition. Archiv fur Biontologie. 4, 143-144.
Petronievics, 1925. Uber die Berliner Archaeornis. Ann. Geol. Peninsule Balkan. 8(1), 1-52.
Hay, 1930. Second bibliography and catalogue of the fossil Vertebrata of North America. Publication 390 of the Carnegie Institute of Washington, Volume 2.
Nopcsa, 1930. Notes on Stegocephalia and Amphibia. Proceedings of the Zoological Society of London. 1930, 979-995.
Lambrecht, 1933. Handbuch der Palaeornithologie. 1024 pp.
Brodkorb, 1963. Catalogue of fossil birds. Part 1 (Archaeopterygiformes through Ardeiformes). Bull. Florida State Mus., Bioi. Sci.. 7, 179-293.
Jensen, 1981. Another look at Archaeopteryx as the worlds oldest bird. Encyclia, The Journal of the Utah Academy of Sciences, Arts, and Letters. 58, 109-128.
Kessler and Jurcsák, 1984. Fossil birds remains in the bauxite from Cornet (Pa¢durea Craiului Mountains, Romania). 75 years of the Laboratory of Paleontology, University of Bucharest, Romania, Special Volume. 129-134.
Paul, 1988. Predatory Dinosaurs of the World. Simon and Schuster Co., New York. 464 pp.
Anonymous, 1994. Korean Pictorial. 1994(2).
Hou, Zhou, Gu and Zhang, 1995. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551 [in Chinese].
Weigert, 1995. Isolierte Zahne von cf. Archaeopteryx sp. aus dem Oberen Jura der Kohlengrube Guimarota (Portugal). N. Jb., Geol. Palaont. Mh. 9, 562-576.
Ji and Ji, 1996. On discovery of the earliest bird fossil in China and the origin of birds. Chinese Geology. 233, 30-33.
Ji and Ji, 1997. A Chinese archaeopterygian, Protarchaeopteryx gen. nov.. Geological Science and Technology. 238, 38-41.
Forster, Sampson, Chiappe and Krause, 1998. The theropod ancestry of birds: New evidence from the Late Cretaceous of Madagascar. Science. 279, 1915-1919.
Cai and Zhao, 1999. A long tailed bird from the Late Cretaceous of Zhejiang. Science in China (series D). 42(4), 434-441.
Martin and Czerkas, 2000. The fossil record of feather evolution in the Mesozoic. American Zoologist. 40(4), 687-694.
Paul, 2002. Dinosaurs of the Air. The Johns Hopkins University Press, Baltimore. 460 pp.
Rauhut, 2002. Dinosaur teeth from the Barremian of Una, Province of Cuenca, Spain. Cretaceous Research. 23, 255-263.
Martin, 2004. A basal archosaurian origin for birds. Acta Zoologica Sinica. 50(6), 978-990.
Ji, Ji, Lu, You, Chen, Liu and Liu, 2005. First avialan bird from China (Jinfengopteryx elegans gen. et sp. nov.). Geological Bulletin of China 24(3): 197-205.
Kurochkin, 2006. Parallel evolution of theropod dinosaurs and birds. Entomological Review. 86(suppl. 1), S45-S58.
Gao, Li, Wei, Pak and Pak, 2009. Early Cretaceous birds and pterosaurs from the Sinuiju series, and geographic extension of the Jehol biota into the Korean peninsula. Journal of the Paleontological Society of Korea. 25(1), 57-61.
Dyke, Benton, Posmosanu and Naish, 2011. Early Cretaceous (Berriasian) birds and pterosaurs from the Cornet bauxite mine, Romania. Palaeontology. 54(1), 79-95.
Xu, You, Du and Han, 2011. An Archaeopteryx-like theropod from China and the origin of Avialae. Nature. 475, 465-470.
Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Vernon, New Jersey. Pan Aves. 189 pp.

Anchiornis Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008
A. huxleyi Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008
Oxfordian, Late Jurassic
Tiaojishan Formation, Liaoning, China
Holotype
- (IVPP V14378) (~340 mm; 110 g; subadult or young adult) posterior cervical vertebrae (eighth cervical 5 mm), thirteen dorsal vertebrae (second dorsal 4.3 mm, seventh dorsal 4.8 mm, eleventh dorsal 5.1 mm), nineteen dorsal ribs, sacrum, seventeen caudal vertebrae (first caudal 2.8 mm, tenth caudal 7.4 mm), chevrons, scapulae (26.8 mm), coracoids, furcula, humeri (41.5 mm), radius, ulna (37.1 mm), radiale, (?)ulnare, metacarpal I, carpometacarpus, phalanx I-1, manual ungual I, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, incomplete ilium (~26.2 mm), partial ischium, femora (43.2 mm), tibiae (67.8 mm), metatarsal I, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, metatarsals V, ungual sheaths, feathers
Referred- (BMNHC PH828) skull (38.5 mm), incomplete mandibles, several dorsal vertebrae, three gastralia, partial sacrum, scapulocoracoids (scapula ~23 mm), furcula, humeri (40 mm), radii, ulnae (35.3 mm), radiales, ulnare, semilunate carpals, metacarpals I (7.8 mm), phalanges I-1, manual unguals I, metacarpals II (20 mm), phalanges II-1, phalanges II-2, manual ungual II, metacarpals III (19.5 mm), phalanx III-1, phalanges III-2, phalanges III-3, manual ungual III, manual claw sheaths, distal femur, tibiae (65.6 mm), astragalus, distal tarsals, metatarsals II, phalanx II-1, phalanx II-2, pedal ungual II, phalanges III-1, phalanges III-2, phalanges III-3, pedal ungual III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal ungual IV, metatarsal V, pedal claw sheaths, body feathers (15-20 mm), remiges (to 62 mm), metatarsal remiges (Li et al., 2010)
(LPM-B00169) skull (63.7 mm), mandibles (53.8 mm), eight cervical vertebrae (series 66.8 mm), thirteen dorsal vertebrae (series 85.4 mm), sixteen dorsal ribs, gastralia, sacrum (31 mm), nineteen caudal vertebrae (first caudal 5.2 mm, thirteenth caudal 14.2 mm, eighteenth caudal 13.5 mm), seventeen chevrons, scapulae (one fragmentary; 45.2 mm) coracoid, furcula, humeri (69 mm), radii (54 mm), ulnae (55.1 mm), radiales, ulnares, semilunate carpals, metacarpals I (12.4 mm), phalanges I-1 (26.2 mm), manual ungual I (15.6 mm), metacarpals II (33.9 mm), phalanges II-1 (21 mm), phalanges II-2 (27 mm), manual unguals II (20.2 mm), metacarpals III (30.5 mm), phalanges III-1 (7.2 mm), phalanges III-2 (8.1 mm), phalanx III-3 (14.2 mm), manual ungual III (13.8 mm), manual claw sheaths, ilia (one partial; 37.4 mm), pubes (61.4 mm), ischium (22.4 mm), femora (66.2 mm), tibiae (106.4 mm), fibula, astragalus, distal tarsal IV, metatarsals I (11.1 mm), pedal ungual I, metatarsals II (51.2 mm), phalanges II-1 (11.5 mm), phalanges II-2 (12.2 mm), pedal unguals II (14.9 mm), metatarsals III (55.2 mm), phalanges III-1 (12.9 mm), phalanges III-2 (11.1 mm), phalanges III-3 (10.5 mm), pedal unguals III (13.7 mm), metatarsals IV (51.9 mm), phalanges IV-1 (10.8 mm), phalanges IV-2 (8.8 mm), phalanges IV-3 (7 mm), phalanges IV-4 (7.6 mm), pedal unguals IV (13.5 mm), metatarsals V (19.2 mm), pedal claw sheaths, body feathers, remiges, metatarsal remiges (Hu et al., 2009)
(STM 0-1) incomplete skeleton including femur (44 mm) and feathers (Zheng et al., 2014)
(STM 0-2) incomplete skeleton including gastralia and femur (70 mm) (Zheng et al., 2014)
(STM 0-3) incomplete skeleton including gastralia, femur (75 mm) and feathers (Zheng et al., 2014)
(STM 0-4) incomplete skeleton including femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-5) incomplete skeleton including femur (41 mm) and feathers (Zheng et al., 2014)
(STM 0-6) material including gastralia (Zheng et al., 2014)
(STM 0-7) incomplete skeleton including femur (64 mm) and feathers (Zheng et al., 2014)
(STM 0-8) incomplete skeleton including gastralia, femur (86 mm) and feathers (Zheng et al., 2014)
(STM 0-9) incomplete skeleton including femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-10) incomplete skeleton including gastralia and femur (47 mm) (Zheng et al., 2014)
(STM 0-11) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-12) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-13) incomplete skeleton including femur (73.5 mm) (Zheng et al., 2014)
(STM 0-14) incomplete skeleton including gastralia and femur (67 mm) (Zheng et al., 2014)
(STM 0-15) material including gastralia (Zheng et al., 2014)
(STM 0-16) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-17) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-18) incomplete skeleton including gastralia, femur (74 mm) and feathers (Zheng et al., 2014)
(STM 0-19) incomplete skeleton including gastralia, femur (68 mm) and feathers (Zheng et al., 2014)
(STM 0-20) incomplete skeleton including gastralia and femur (52 mm) (Zheng et al., 2014)
(STM 0-21) incomplete skeleton including femur (52 mm) and feathers (Zheng et al., 2014)
(STM 0-22) incomplete skeleton including gastralia (Zheng et al., 2014)
(STM 0-23) incomplete skeleton including gastralia and femur (75 mm) (Zheng et al., 2014)
(STM 0-24) material including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-25) material including gastralia and femur (62 mm) (Zheng et al., 2014)
(STM 0-26) incomplete skeleton including gastralia and femur (93 mm) (Zheng et al., 2014)
(STM 0-27) incomplete skeleton including gastralia, femur (52 mm) and feathers (Zheng et al., 2014)
(STM 0-28) incomplete skeleton including femur (75 mm) and feathers (Zheng et al., 2014)
(STM 0-29) incomplete skeleton including gastralia, femur ( mm) and feathers (Zheng et al., 2014)
(STM 0-30) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-31) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-32) incomplete skeleton including gastralia, femur (40 mm) and feathers (Zheng et al., 2014)
(STM 0-33) material including femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-34) incomplete skeleton including gastralia and femur (70 mm) (Zheng et al., 2014)
(STM 0-35) incomplete skeleton including gastralia, femur (80 mm) and feathers (Zheng et al., 2014)
(STM 0-36) incomplete skeleton including femur (71 mm) and feathers (Zheng et al., 2014)
(STM 0-37) incomplete skeleton including gastralia, femur (67 mm) and feathers (Zheng et al., 2014)
(STM 0-38) incomplete skeleton including femur (45 mm) and feathers (Zheng et al., 2014)
(STM 0-39) incomplete skeleton including gastralia, femur (40 mm) and feathers (Zheng et al., 2014)
(STM 0-40) incomplete skeleton including gastralia, femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-41) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-42) incomplete skeleton including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-43) material including femur (72 mm) (Zheng et al., 2014)
(STM 0-44) incomplete skeleton including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-45) (Zheng et al., 2014)
(STM 0-46) material including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-47) incomplete skeleton including gastralia, femur (68 mm) and feathers (Zheng et al., 2014)
(STM 0-48) incomplete skeleton including gastralia, femur (71 mm) and feathers (Zheng et al., 2014)
(STM 0-49) material including gastralia and femur (67 mm) (Zheng et al., 2014)
(STM 0-50) incomplete skeleton including gastralia, femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-51) material including gastralia and femur (~50 mm) (Zheng et al., 2014)
(STM 0-52) incomplete skeleton including gastralia, femur (57 mm) and feathers (Zheng et al., 2014)
(STM 0-53) incomplete skeleton including gastralia, femur (56 mm) and feathers (Zheng et al., 2014)
(STM 0-54) incomplete skeleton including femur (49.5 mm) and feathers (Zheng et al., 2014)
(STM 0-55) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-56) incomplete skeleton including gastralia, femur (42 mm) and feathers (Zheng et al., 2014)
(STM 0-57) incomplete skeleton including femur (44 mm) and feathers (Zheng et al., 2014)
(STM 0-58) incomplete skeleton including femur (49 mm) and feathers (Zheng et al., 2014)
(STM 0-59) incomplete skeleton including gastralia, femur (47 mm) and feathers (Zheng et al., 2014)
(STM 0-60) material including gastralia, femur (45 mm) and feathers (Zheng et al., 2014)
(STM 0-61) incomplete skeleton including femur (66 mm) (Zheng et al., 2014)
(STM 0-62) incomplete skeleton including femur (49 mm) and feathers (Zheng et al., 2014)
(STM 0-63) material including gastralia, femur (~60 mm) and feathers (Zheng et al., 2014)
(STM 0-64) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-66) specimen including femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-67) material including gastralia, femur (~43 mm) and feathers (Zheng et al., 2014)
(STM 0-68) incomplete skeleton including gastralia and feathers (Zheng et al., 2014)
(STM 0-69) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-70) material including femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-71) incomplete skeleton including gastralia, femur (64 mm) and feathers (Zheng et al., 2014)
(STM 0-72) incomplete skeleton including gastralia and femur (70 mm) (Zheng et al., 2014)
(STM 0-73) incomplete skeleton including gastralia and femur (62 mm) (Zheng et al., 2014)
(STM 0-74) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-75) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-76) incomplete skeleton including gastralia, femur (55 mm) and feathers (Zheng et al., 2014)
(STM 0-77) incomplete skeleton including gastralia and femur (49 mm) (Zheng et al., 2014)
(STM 0-78) incomplete skeleton including gastralia and femur (51 mm) (Zheng et al., 2014)
(STM 0-79) incomplete skeleton including gastralia, femur (49 mm) and feathers (Zheng et al., 2014)
(STM 0-80) incomplete skeleton including gastralia, femur (~38 mm) and feathers (Zheng et al., 2014)
(STM 0-81) material including gastralia and femur (~32 mm) (Zheng et al., 2014)
(STM 0-82) incomplete skeleton including gastralia, femur (47 mm) and feathers (Zheng et al., 2014)
(STM 0-83) material including gastralia and femur (~39 mm) (Zheng et al., 2014)
(STM 0-84) material including gastralia and femur (52 mm) (Zheng et al., 2014)
(STM 0-85) incomplete skeleton including gastralia and femur (44 mm) (Zheng et al., 2014)
(STM 0-86) incomplete skeleton including femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-87) material including gastralia, femur (62 mm) and feathers (Zheng et al., 2014)
(STM 0-88) material including gastralia, femur (~66 mm) (Zheng et al., 2014)
(STM 0-89) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-90) material including gastralia, femur (79 mm) and feathers (Zheng et al., 2014)
(STM 0-91) material including gastralia and femur (70 mm) (Zheng et al., 2014)
(STM 0-92) incomplete skeleton including gastralia and femur (64 mm) (Zheng et al., 2014)
(STM 0-93) incomplete skeleton including gastralia, femur (69 mm) and feathers (Zheng et al., 2014)
(STM 0-94) material including gastralia (Zheng et al., 2014)
(STM 0-95) material including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-96) incomplete skeleton including gastralia, femur (~48 mm) and feathers (Zheng et al., 2014)
(STM 0-97) incomplete skeleton including gastralia and femur (58 mm) (Zheng et al., 2014)
(STM 0-98) incomplete skeleton including feathers (Zheng et al., 2014)
(STM 0-99) incomplete skeleton including gastralia and femur (76 mm) (Zheng et al., 2014)
(STM 0-100) incomplete skeleton including femur (74 mm) (Zheng et al., 2014)
(STM 0-101) material including femur (60 mm) (Zheng et al., 2014)
(STM 0-102) incomplete skeleton including gastralia and femur (66 mm) (Zheng et al., 2014)
(STM 0-103) (Zheng et al., 2014)
(STM 0-104) incomplete skeleton including gastralia, femur (43 mm) and feathers (Zheng et al., 2014)
(STM 0-105) incomplete skeleton including gastralia, femur (72 mm) and feathers (Zheng et al., 2014)
(STM 0-106) incomplete skeleton including gastralia, femur (75 mm) and feathers (Zheng et al., 2014)
(STM 0-107) material including feathers (Zheng et al., 2014)
(STM 0-108) material including gastralia, femur (62 mm) and feathers (Zheng et al., 2014)
(STM 0-109) material including feathers (Zheng et al., 2014)
(STM 0-110) incomplete skeleton including gastralia, femur (57 mm) and feathers (Zheng et al., 2014)
(STM 0-111) incomplete skeleton including gastralia, femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-112) incomplete skeleton including gastralia, femur (~63 mm) and feathers (Zheng et al., 2014)
(STM 0-113) material including gastralia and femur (48 mm) (Zheng et al., 2014)
(STM 0-114) material including femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-115) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-116) material including femur (41 mm) (Zheng et al., 2014)
(STM 0-117) material including feathers (Zheng et al., 2014)
(STM 0-118) incomplete skeleton including gastralia, femur (62 mm) and feathers (Zheng et al., 2014)
(STM 0-119) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-120) material including gastralia, femur (48 mm) and feathers (Zheng et al., 2014)
(STM 0-121) incomplete skeleton including gastralia and femur (44 mm) (Zheng et al., 2014)
(STM 0-122) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-123) material including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-124) material including feathers (Zheng et al., 2014)
(STM 0-125) material including femur (59 mm) and feathers (Zheng et al., 2014)
(STM 0-126) incomplete skeleton including gastralia, femur (54 mm) and feathers (Zheng et al., 2014)
(STM 0-127) material including femur (70 mm) (Zheng et al., 2014)
(STM 0-128) material including gastralia and femur (~50 mm) (Zheng et al., 2014)
(STM 0-129) material including gastralia, femur (~46 mm) and feathers (Zheng et al., 2014)
(STM 0-130) material including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-131) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-132) incomplete skeleton including gastralia and femur (40 mm) (Zheng et al., 2014)
(STM 0-133) (Zheng et al., 2014)
(STM 0-134) incomplete skeleton including femur (40 mm) and feathers (Zheng et al., 2014)
(STM 0-135) incomplete skeleton including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-136) material including gastralia, femur (47 mm) and feathers (Zheng et al., 2014)
(STM 0-137) incomplete skeleton including gastralia, femur (72 mm) and feathers (Zheng et al., 2014)
(STM 0-138) incomplete skeleton including gastralia, femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-139) incomplete skeleton including feathers (Zheng et al., 2014)
(STM 0-140) incomplete skeleton including gastralia, femur (43 mm) and feathers (Zheng et al., 2014)
(STM 0-141) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-142) incomplete skeleton including gastralia, femur (41 mm) and feathers (Zheng et al., 2014)
(STM 0-143) incomplete skeleton including gastralia, femur (68 mm) and feathers (Zheng et al., 2014)
(STM 0-144) incomplete skeleton including gastralia, femur (~50 mm) and feathers (Zheng et al., 2014)
(STM 0-145) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-146) material including gastralia (Zheng et al., 2014)
(STM 0-147) incomplete skeleton including gastralia and femur (~35 mm) (Zheng et al., 2014)
(STM 0-148) incomplete skeleton including gastralia and femur (40 mm) (Zheng et al., 2014)
(STM 0-149) material including feathers (Zheng et al., 2014)
(STM 0-150) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-151) incomplete skeleton including femur (69 mm) and feathers (Zheng et al., 2014)
(STM 0-152) incomplete skeleton including gastralia, femur (68 mm) and feathers (Zheng et al., 2014)
(STM 0-153) material including gastralia, femur (44 mm) and feathers (Zheng et al., 2014)
(STM 0-154) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-155) incomplete skeleton including gastralia, femur (73 mm) and feathers (Zheng et al., 2014)
(STM 0-156) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-157) incomplete skeleton including gastralia, femur (54 mm) and feathers (Zheng et al., 2014)
(STM 0-158) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-159) material including gastralia, femur (58 mm) and feathers (Zheng et al., 2014)
(STM 0-160) incomplete skeleton including gastralia (Zheng et al., 2014)
(STM 0-161) incomplete skeleton including gastralia and femur (75 mm) (Zheng et al., 2014)
(STM 0-162) incomplete skeleton including gastralia, femur (~53 mm) and feathers (Zheng et al., 2014)
(STM 0-163) material including femur (48 mm) and feathers (Zheng et al., 2014)
(STM 0-164) incomplete skeleton including gastralia, femur (47 mm) and feathers (Zheng et al., 2014)
(STM 0-165) incomplete skeleton including gastralia, femur (63 mm) and feathers (Zheng et al., 2014)
(STM 0-166) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-167) incomplete skeleton including gastralia and femur (45 mm) (Zheng et al., 2014)
(STM 0-168) incomplete skeleton including gastralia and femur (56 mm) (Zheng et al., 2014)
(STM 0-169) incomplete skeleton including gastralia, femur (72 mm) and feathers (Zheng et al., 2014)
(STM 0-170) incomplete skeleton including gastralia, femur (64 mm) and feathers (Zheng et al., 2014)
(STM 0-171) incomplete skeleton including gastralia, femur (53 mm) and feathers (Zheng et al., 2014)
(STM 0-172) material including femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-173) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-174) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-175) incomplete skeleton including gastralia, femur (75 mm) and feathers (Zheng et al., 2014)
(STM 0-176) incomplete skeleton including gastralia and femur (68 mm) (Zheng et al., 2014)
(STM 0-177) incomplete skeleton including gastralia, femur (69 mm) and feathers (Zheng et al., 2014)
(STM 0-178) incomplete skeleton including gastralia, femur (63 mm) and feathers (Zheng et al., 2014)
(STM 0-179) incomplete skeleton including femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-180) material including feathers (Zheng et al., 2014)
(STM 0-181) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-182) incomplete skeleton including gastralia, femur (43 mm) and feathers (Zheng et al., 2014)
(STM 0-183) incomplete skeleton including gastralia and femur (50 mm) (Zheng et al., 2014)
(STM 0-184) incomplete skeleton including gastralia (Zheng et al., 2014)
(STM 0-185) incomplete skeleton including femur (65 mm) (Zheng et al., 2014)
(STM 0-186) incomplete skeleton including gastralia, femur (46 mm) and feathers (Zheng et al., 2014)
(STM 0-187) incomplete skeleton including gastralia, femur (42 mm) and feathers (Zheng et al., 2014)
(STM 0-188) incomplete skeleton including gastralia, femur (75 mm) and feathers (Zheng et al., 2014)
(STM 0-189) incomplete skeleton including gastralia and femur (44 mm) (Zheng et al., 2014)
(STM 0-190) incomplete skeleton including gastralia and femur (54 mm) (Zheng et al., 2014)
(STM 0-191) incomplete skeleton including gastralia and femur (68 mm) (Zheng et al., 2014)
(STM 0-192) incomplete skeleton including gastralia and femur (75 mm) (Zheng et al., 2014)
(STM 0-193) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-194) incomplete skeleton including gastralia, femur (46 mm) and feathers (Zheng et al., 2014)
(STM 0-195) material including femur (43 mm) (Zheng et al., 2014)
(STM 0-196) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-197) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-198) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-199) material including gastralia and feathers (Zheng et al., 2014)
(STM 0-200) incomplete skeleton including gastralia (Zheng et al., 2014)
(STM 0-201) material including gastralia, femur (65 mm) and feathers (Zheng et al., 2014)
(STM 0-202) incomplete skeleton including gastralia, femur (60 mm) and feathers (Zheng et al., 2014)
(STM 0-203) incomplete skeleton including gastralia and femur (62 mm) (Zheng et al., 2014)
(STM 0-204) incomplete skeleton including gastralia, femur (64 mm) and feathers (Zheng et al., 2014)
(STM 0-205) material including femur (60 mm) (Zheng et al., 2014)
(STM 0-206) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-207) incomplete skeleton including gastralia, femur (51 mm) and feathers (Zheng et al., 2014)
(STM 0-208) incomplete skeleton including femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-209) incomplete skeleton including gastralia, femur (50 mm) and feathers (Zheng et al., 2014)
(STM 0-210) incomplete skeleton including gastralia and feathers (Zheng et al., 2014)
(STM 0-211) incomplete skeleton including femur (58 mm) and feathers (Zheng et al., 2014)
(STM 0-212) incomplete skeleton including gastralia, femur (45 mm) and feathers (Zheng et al., 2014)
(STM 0-213) incomplete skeleton including gastralia, femur (71 mm) and feathers (Zheng et al., 2014)
(STM 0-214) incomplete skeleton including gastralia and feathers (Zheng et al., 2014)
(STM 0-215) incomplete skeleton including femur (68 mm) and feathers (Zheng et al., 2014)
(STM 0-216) incomplete skeleton including femur (67 mm) and feathers (Zheng et al., 2014)
(STM 0-217) incomplete skeleton including gastralia, femur (70 mm) and feathers (Zheng et al., 2014)
(STM 0-218) material including gastralia and femur (66 mm) (Zheng et al., 2014)
(STM 0-219) material including gastralia, femur (~46 mm) and feathers (Zheng et al., 2014)
(STM 0-220) material including gastralia, femur (~50 mm) and feathers (Zheng et al., 2014)
(STM 0-221) incomplete skeleton including femur (73 mm) and feathers (Zheng et al., 2014)
(STM 0-222) material including femur (50 mm) (Zheng et al., 2014)
(STM 0-223) material including gastralia, femur (46 mm) and feathers (Zheng et al., 2014)
(STM 0-224) incomplete skeleton including gastralia, femur (80 mm) and feathers (Zheng et al., 2014)
(STM 0-225) incomplete skeleton including gastralia and femur (60 mm) (Zheng et al., 2014)
(STM 0-226) (Zheng et al., 2014)
(YFGP-T5199) (470 mm adult) skull (59.5 mm), mandibles, eight cervical vertebrae (series 56.5 mm), cervical ribs, seven dorsal vertebrae (series 97.5 mm), dorsal ribs, gastralia, caudal series (236.5 mm; proximal caudal 6.5, distal caudal 16 mm), chevron, scapulae (31 mm), coracoids, furcula, humeri (70 mm), radii, ulnae (59.5 mm), radiales, ulnares, semilunate carpal, metacarpals I (14 mm), phalanges I-1 (27 mm), manual unguals I (16.5 mm), metacarpals II (~38 mm), phalanges II-1 (25 mm), phalanges II-2, manual ungual II, metacarpals III (~31 mm), phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, ilia (35.5 mm), pubes (49.5 mm), ischium (16 mm), femora (69.5 mm), tibiotarsi (106 mm), metatarsals I (12 mm), phalanges I-1, pedal unguals I, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III (61 mm), phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanx IV-4, pedal ungual IV, metatarsal V, body feathers, remiges, retrices (Lindgren et al., 2015)
five complete skeletons (Pei et al., 2013)
Diagnosis- (after Xu et al., 2008) ventral surface of coracoid sculptured by numerous small pits; extremely short ischium (less than one-fourth of the femoral length).
(after Hu et al., 2009) elongate tibia (157-161% of femoral length).
Comments- While Xu et al. (2008) used a version of the Theropod Working Group matrix with added characters from Xu's thesis to place Anchiornis as an avialan more basal than Archaeopteryx, Hu et al. (2009) used Senter's version of the TWG matrix to place it as a troodontid more derived than Sinovenator but less so than Mei and other taxa. Xu et al. (2011) found it to be an archaeopterygid, with that group basal in Deinonychosauria. Pei et al. (2013) found it to be a basalmost troodontid. Among more recent analyses, Senter et al. (2012) and Brusatte et al. (2014) found it to be a troodontid basal to Sinovenator and Mei, while Foth et al. (2014) and Lee et al. (2014) found it to be an avialan more basal than Archaeopteryx.
References- Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008. A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin. Chinese Science Bulletin. 54(3), 430-435.
Hu, Hou, Zhang and Xu, 2009. A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus. Nature. 461, 640-643.
Li, Gao, Vinther, Shawkey, Clarke, D'Alba, Meng, Briggs and Prum, 2010. Plumage color patterns of an extinct dinosaur. Science. 327 (5971), 1369-1372.
Xu, You, Du and Han, 2011. An Archaeopteryx-like theropod from China and the origin of Avialae. Nature. 475, 465-470.
Senter, Kirkland, DeBlieux, Madsen and Toth, 2012. New dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the evolution of the dromaeosaurid tail. PLoS ONE. 7(5), e36790.
Pei, Li, Meng, Norell and Gao, 2013. Excellently preserved new specimens of Anchiornis and the implication of early evolution in Paraves. Journal of Vertebrate Paleontology. Program and Abstracts 2013, 189.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.
Zheng, O'Connor, Wang, Wang, Zhang and Zhou, 2014. On the absence of sternal elements in Anchiornis (Paraves) and Sapeornis (Aves) and the complex early evolution of the avian sternum. Proceedings of the National Academy of Sciences. 111(38), 13900-13905.
Lindgren, Sjövall, Carney, Cincotta, Uvdal, Hutcheson, Gustafsson, Lefèvre, Escuillié, Heimdal, Engdahl, Gren, Kear, Wakamatsu, Yans and Godefroit, 2015. Molecular composition and ultrastructure of Jurassic paravian feathers. Scientific Reports. 5, 13520.

Archaeopteryx Meyer, 1861
= Griphosaurus Wagner, 1862 (nomen rejectum)
= Griphornis Owen vide Woodward, 1862 (nomen rejectum)
= Archaeornis Petronievics vide Petroneivics and Woodward, 1917
= Jurapteryx Howgate, 1985
= Wellnhoferia Elzanowski, 2001
Other definitions- (Archaeopteryx lithographica <- Passer domesticus) (modified from Sereno, 1998)
A. lithographica Meyer, 1861
= Pterodactylus (Rhamphorhynchus) crassipes Meyer, 1857 (nomen rejectum)
= Griphornis longicaudatus Owen vide Woodward, 1862 (nomen rejectum)
= Griphosaurus problematicus Wagner vide Woodward, 1862 (nomen rejectum)
= Archaeopteryx macrura Owen, 1863 (nomen rejectum)
= Archaeopteryx siemensii Dames, 1897
= Archaeornis siemensii (Dames, 1897) Petronievics vide Petroneivics and Woodward, 1917
= Archaeopteryx oweni Petronievics, 1921
= Griphosaurus longicaudatus (Owen vide Woodward, 1862) Owen vide Brodkorb, 1963
= Scaphognathus crassipes (Meyer, 1857) Wellnhofer, 1970
= Archaeopteryx crassipes (Meyer, 1857) Ostrom, 1972
= Archaeopteryx recurva Howgate, 1984
= Jurapteryx recurva (Howgate, 1984) Howgate, 1985
= Archaeopteryx bavarica Wellnhofer, 1993
= Wellnhoferia grandis Elzanowski, 2001
Early Tithonian, Late Jurassic
Solnhofen Formation, Germany

Neotype- (BMNH 37001; London specimen; holotype of Griphosaurus; holotype of Griphosaurus problematicus; holotype of Griphornis longicaudatus; holotype of Archaeopteryx macrura; holotype of Archaeopteryx oweni) (.46 m, 450 g, 460 day old subadult) premaxilla, maxillary fragment, partial quadrate, braincase, ninth cervical vertebra, tenth cervical vertebra, first dorsal vertebra (~7 mm), second dorsal vertebra, third dorsal vertebra, fourth dorsal vertebra, fifth dorsal vertebra, sixth dorsal vertebra (~7 mm), seventh dorsal vertebra (~7 mm), eighth dorsal vertebra, ninth dorsal vertebra, tenth dorsal vertebra, eleventh dorsal vertebra (5.5 mm), twelfth dorsal vertebra (5.5 mm), thirteenth dorsal vertebra (5.5 mm), dorsal ribs, gastralia, (sacrum- ~33 mm) first sacral vertebra, second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, fifth caudal vertebra (5.4 mm), fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra (6 mm), seventh caudal vertebra (6.5 mm), eighth caudal vertebra (8 mm), ninth caudal vertebra (~10.5 mm), tenth caudal vertebra (~10.5 mm), eleventh caudal vertebra (11.7 mm), twelfth caudal vertebra (12.3 mm), thirteenth caudal vertebra (13 mm), fourteenth caudal vertebra (12.3 mm), fifteenth caudal vertebra (12.5 mm), sixteenth caudal vertebra (12.4 mm), seventeenth caudal vertebra (11.4 mm), eighteenth caudal vertebra (11.4 mm), nineteenth caudal vertebra (10.5 mm), twentieth caudal vertebra (9.3 mm), twenty-first caudal vertebra (8.5 mm), twenty-second caudal vertebra (7 mm), twenty-third caudal vertebra (4.3 mm), scapulae (46 mm), coracoid, furcula, humeri (75 mm), radii (65 mm), ulnae (67.5 mm), radiale, ulnare, semilunate carpal, distal phalanx I-1, manual ungual I, metacarpal II (34.4 mm), metacarpal III, manual phalanx, ilia (38 mm), pubes (51.5 mm), ischium (~25.5 mm), femora (60.5 mm), tibiae (80.5 mm), astragalus, metatarsal I fragment, phalanx I-1 (8.8 mm), pedal ungual I (~6.8 mm), metatarsal II (~40 mm), phalanx II-1 (11 mm), phalanx II-2 (11 mm), pedal ungual II (~11 mm), metatarsal III (44 mm), phalanx III-1 (12.7 mm), phalanx III-2 (11 mm), phalanx III-3 (~9.5 mm), pedal ungual III (~14 mm), distal phalanx IV-3, phalanx IV-4 , pedal ungual IV (~11 mm), metatarsal V (7.9 mm), remiges, retrices (Meyer, 1861b)
Referred- (BMMS 500; Solnhofen specimen; sixth specimen; holotype of Wellnhoferia grandis) (1.1 kg, 530 day old subadult) partial skull (~65 mm), sclerotic plates, partial mandible (~61 mm), axis, third cervical vertebra (~9 mm), partial fourth cervical vertebra, cervical ribs, partial eleventh dorsal vertebra, twelfth dorsal vertebra (~8 mm), thirteenth dorsal vertebra (~8 mm), fourteenth dorsal vertebra (8.8 mm), dorsal ribs, gastralia, (sacrum ~28 mm) partial first sacral vertebra, second sacral neural spine, third sacral neural arch, fourth sacral transverse process, fifth sacral neural arch, first caudal vertebra (5.4 mm), second caudal vertebra (6.2 mm), third caudal vertebra (6.7 mm), fourth caudal vertebra (6.5 mm), fifth caudal vertebra (7.5 mm), sixth caudal vertebra (9 mm), seventh caudal vertebra (9.7 mm), eighth caudal vertebra (9.5 mm), ninth caudal vertebra (13 mm), tenth caudal vertebra (14.2 mm), eleventh caudal vertebra (14.3 mm), twelfth caudal vertebra (15.5 mm), thirteenth caudal vertebra (15 mm), fourteenth caudal vertebra (~11 mm), partial fifteenth caudal vertebra (~11 mm), chevrons, incomplete scapulae (~51 mm), coracoids (24.5 mm), partial furcula, incomplete humeri (83 mm), partial radii (~69 mm), partial ulnae (~72 mm), partial metacarpals I, phalanges I-1 (28, 28.4 mm), manual unguals I (17.5 mm), incomplete metacarpals II (~36.6 mm), phalanges II-1 (20.1 mm), phalanges II-2 (27.5 mm), manual unguals II (17.8 mm), incomplete metacarpals III, phalanx III-1 (8 mm), phalanges III-2 (6.5 mm), phalanges III-3 (17.8 mm), manual unguals III (12 mm), manual claw sheaths, ilia (~38 mm), pubes (59.3 mm), partial ischium (~24.5 mm), femora (~67 mm), tibiae (92 mm), fibula (82.4 mm), astragali, calcanea, distal tarsals, metatarsals I (9.9 mm), phalanx I-1 (11 mm), pedal ungual I (~9.8 mm), metatarsus (II 45 mm, III ~47.5 mm, IV 45 mm), phalanges II-1 (12 mm), phalanges II-2 (12.5 mm), pedal unguals II (~14 mm), phalanges III-1 (one proximal; 13.7 mm), phalanx III-2 (11.8 mm), phalanx III-3 (10.5 mm), pedal ungual III (~10 mm), phalanx IV-1 (10 mm), phalanx IV-2 (8.5 mm), phalanx IV-3 (9.5 mm), pedal ungual IV (~12.6 mm), metatarsal V (10.5 mm), pedal claw sheaths, remiges (Wellnhofer, 1988)
(BMMS coll.; chicken wing; ninth specimen) (420 day old juvenile) humerus (70.1 mm), radius (~59 mm), ulna (62 mm), semilunate carpal, metacarpal I (10 mm), phalanx I-1 (22.5 mm), metacarpal II (31.3 mm), phalanx II-1 (~16.5 mm), phalanx II-2 (21 mm), manual ungual II (~15 mm), metacarpal III (27.5 mm), phalanx III-1 (6.3 mm), phalanx III-2 (5 mm), phalanx III-3 (14.4 mm), manual ungual III (~10 mm), remiges (Wellnhofer and Roper, 2005)
(BSP 1999 I 50; Munich specimen; Solnhofen-Aktien-Verein specimen; seventh specimen; holotype of Archaeopteryx bavarica) (270 day old juvenile) partial skull (~45 mm), mandibles (40 mm), atlas, axis, third cervical vertebra, fourth cervical vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh cervical vertebra, eighth cervical vertebra, ninth cervical neural spine, tenth cervical neural spine, cervical ribs, first dorsal neural spine, partial second dorsal vertebra, third dorsal neural spine, seventh dorsal neural spine, eighth dorsal vertebra, ninnth dorsal vertebra, tenth dorsal vertebra, eleventh dorsal vertebra, twelfth dorsal vertebra, thirteenth dorsal vertebra, dorsal ribs, gastralia, (sacrum 22 mm) first sacral centrum, second sacral centrum, fifth sacral centrum, first caudal vertebra, second caudal vertebra, third caudal vertebra, fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra, seventh caudal vertebra, eighth caudal vertebra, ninth caudal vertebra, tenth caudal vertebra, eleventh caudal vertebra, twelfth caudal vertebra, thirteenth caudal vertebra, fourteenth caudal vertebra, fifteenth caudal vertebra, sixteenth caudal vertebra, seventeenth caudal vertebra, eighteenth caudal vertebra, nineteenth caudal vertebra, twentieth caudal vertebra, twenty-first caudal vertebra, chevrons, scapulae (34.5 mm), coracoids (15 mm), partial furcula, humeri (~55 mm), radii (53 mm), ulnae (53 mm), ulnare, semilunate carpal, distal carpal III, metacarpal I (7 mm), phalanges I-1 (20 mm), manual unguals I (9.5 mm), metacarpals II (one distal; 25 mm), phalanges II-1 (12.5 mm), phalanges II-2 (18.5 mm), manual unguals II (10 mm), metacarpals III (one distal; ~23 mm), phalanges III-1 (one partial; 4.9 mm), phalanx III-2 (4.2 mm), phalanges III-3 (12 mm), manual unguals III (6.5 mm), manual claw sheaths, ilium (~27.5 mm), pubis (40 mm), ischia (~16 mm), incomplete femora (~46.5 mm), tibiae (~71.5 mm), fibula (69.5 mm), astragali, calcanea, two distal tarsals, metatarsals I, phalanges I-1 (7.1 mm), pedal ungual I (5.2 mm), metatarsals II (~36 mm), phalanges II-1 (~8 mm), phalanges II-2 (~8 mm), pedal unguals II (7, 7.4 mm), metatarsals III (40.5 mm), phalanges III-1 (10.8 mm), phalanges III-2 (8.5 mm), phalanges III-3 (8.4 mm), pedal unguals III (6.8, 7 mm), metatarsal IV (37 mm), phalanx IV-1 (8 mm), phalanx IV-2 (6 mm), phalanges IV-3 (~5.5 mm), phalanges IV-4 (7 mm), pedal unguals IV (6.2 mm), metatarsal V (~10 mm), pedal claw sheaths, remiges, retrices (Wellnhofer, 1993)
?(HMN.Ab.100; BSP coll.; holotype of Archaeopteryx lithographica) secondary feather (58 mm) (Meyer, 1861a)
(HMN MB. 1880/81; Berlin specimen; second specimen; holotype of Archaeopteryx seimensii) (.405 m, 340 g; 330 day old juvenile) skull (45 mm), sclerotic ring, mandible (43.5 mm), hyoids, axis (5 mm), third cervical vertebra (6.5 mm), fourth cervical vertebra (9 mm), fifth cervical vertebra (9.5 mm), sixth cervical vertebra (8 mm), seventh cervical vertebra (9 mm), eighth cervical vertebra, ninth cervical vertebra (8 mm), tenth cervical vertebra (7.7 mm), first dorsal vertebra (7.3 mm), second dorsal vertebra (5.5 mm), third dorsal vertebra (5.9 mm), fourth dorsal vertebra (5.7 mm), fifth dorsal vertebra (5.5 mm), sixth dorsal vertebra (5.5 mm), seventh dorsal vertebra (6.1 mm), eighth dorsal vertebra (6.1 mm), ninth dorsal vertebra (6.3 mm), tenth dorsal vertebra (6.2 mm), eleventh dorsal vertebra (6.2 mm), twelfth dorsal vertebra, thirteenth dorsal vertebra, dorsal ribs, gastralia, (sacrum ~31 mm) first sacral vertebra (6.5 mm), second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, second caudal vertebra (5.3 mm), third caudal vertebra (~4 mm), fourth caudal vertebra (~4 mm), fifth caudal vertebra (6 mm), sixth caudal vertebra (6.5 mm), seventh caudal vertebra (7.3 mm), eighth caudal vertebra (9 mm), ninth caudal vertebra (10.5 mm), tenth caudal vertebra (11.3 mm), eleventh caudal vertebra (11.3 mm), twelfth caudal vertebra (~11.5 mm), thirteenth caudal vertebra (~11.5 mm), fourteenth caudal vertebra (~10.5 mm), fifteenth caudal vertebra (10 mm), sixteenth caudal vertebra (10 mm), seventeenth caudal vertebra (~10 mm), eighteenth caudal vertebra (~9.5 mm), nineteenth caudal vertebra (8.5 mm), twentieth caudal vertebra (8 mm), twenty-first caudal vertebra (7.2 mm), twenty-second caudal vertebra (5.5 mm), twenty-third caudal vertebra, scapulae (42 mm), coracoids, humeri (63.5 mm), radii (54.4 mm), ulnae (55 mm), radiales, ulnares, semilunate carpals, distal carpal III, metacarpals I (8.3 mm), phalanges I-1 (20.5 mm), manual unguals I (~12.5 mm), metacarpals II (28 mm), phalanges II-1 (15.5 mm), phalanges II-2 (19.4 mm), manual unguals II (~16 mm), metacarpals III (24.8 mm), phalanges III-1 (6.4 mm), phalanges III-2 (4.2 mm), phalanges III-3 (12.3 mm), manual unguals III (~9.5 mm), manual claw sheaths, ilium (~32 mm), pubis (48 mm), incomplete ischium (~20 mm), femora (52.2 mm), tibiae (71 mm), astragalus, calcaneum, distal tarsal III, distal tarsal IV, metatarsal I, phalanges I-1 (5.2, 5.5 mm), pedal ungual I (5.5 mm), metatarsal II (~35 mm), phalanx II-1 (8.2 mm), phalanx II-2 (7 mm), pedal ungual II (12.5 mm), metatarsals III (~37 mm), phalanges III-1 (9.6 mm), phalanges III-2 (9 mm), phalanges III-3 (8.2 mm), pedal unguals III (8.8 mm), metatarsal IV (~32.5 mm), phalanges IV-1 (7 mm), phalanges IV-2 (6.4, 6.6 mm), phalanges IV-3 (4.9 mm), phalanges IV-4 (5.6, 5.8 mm), pedal unguals IV (6.8 mm), body feathers, remiges, retrices (Dames, 1884)
(JM SoS 2257; Eichstatt specimen; fifth specimen; holotype of Archaeopteryx recurva) (.29 m, 180 g; 110 day old juvenile) skull (39 mm), sclerotic ring, mandible (36.5 mm), atlas, axis (3.7 mm), third cervical vertebra (~4.5 mm), fourth cervical vertebra (~6 mm), fifth cervical vertebra (~7 mm), sixth cervical vertebra (~5.5 mm), seventh cervical vertebra (~5 mm), eighth cervical vertebra (~5 mm), ninth cervical vertebra (~4.5 mm), tenth cervical vertebra (~3.5 mm), cervical ribs, first dorsal vertebra (4 mm), second dorsal vertebra, partial third dorsal vertebra, partial fifth dorsal vertebra (4 mm), sixth dorsal vertebra (4 mm), seventh dorsal vertebra (~4 mm), eighth dorsal vertebra (4.5 mm), ninth dorsal vertebra (~5 mm), tenth dorsal vertebra (~4.5 mm), eleventh dorsal vertebra, twelfth dorsal vertebra (4 mm), thirteenth dorsal vertebra (4 mm), dorsal ribs, gastralia, (sacrum ~16.5 mm), first sacral centrum (3.7 mm), second sacral centrum (3.4 mm), third sacral centrum (3.1 mm), fourth sacral centrum (3.2 mm), fifth sacral centrum, first caudal vertebra (3 mm), second caudal vertebra (3.3 mm), third caudal vertebra (3.5 mm), fourth caudal vertebra (~4 mm), fifth caudal vertebra (4.7 mm), sixth caudal vertebra (5.4 mm), seventh caudal vertebra (6.4 mm), eighth caudal vertebra (7.2 mm), ninth caudal vertebra (7.9 mm), tenth caudal vertebra (8.4 mm), eleventh caudal vertebra (8.5 mm), twelfth caudal vertebra (8.6 mm), thirteenth caudal vertebra (8.3 mm), fourteenth caudal vertebra (8.3 mm), fifteenth caudal vertebra (8 mm), sixteenth caudal vertebra (7.7 mm), seventeenth caudal vertebra (7.4 mm), eighteenth caudal vertebra (6.9 mm), nineteenth caudal vertebra (6.6 mm), twentieth caudal vertebra (~5.5 mm), twenty-first caudal vertebra (4.2 mm), twenty-second caudal vertebra (4 mm), twenty-third caudal vertebra, seventeen chevrons, incomplete scapulae, partial coracoids, humeri (41.5 mm), radii (35 mm), ulnae (36.5 mm), radiales, ulnare, semilunate carpals, distal carpals III, metacarpals I (one proximal; 5.5 mm), phalanges I-1 (one distal; 15.6 mm), manual unguals I (9.8 mm), metacarpals II (one incomplete; 17.8 mm), phalanges II-1 (10.2 mm), phalanges II-2 (15.1 mm), manual unguals II (10.8 mm), metacarpals III (one incomplete; 16.5 mm), phalanx III-1 (4.2 mm), phalanx III-2 (3 mm), phalanx III-3 (9.8 mm), manual unguals III (6.5 mm), manual claw sheaths, incomplete ilium (~20 mm), pubes (31.5 mm), ischia (14.5 mm), femora (37 mm), tibiae (~53 mm), fibula (50.5 mm), astragali, distal tarsal III, distal tarsal IV, metatarsals I, phalanges I-1 (5.5 mm), pedal unguals I (3.5 mm), partial metatarsals II (28.3 mm), phalanges II-1 (~7.1 mm), phalanges II-2 (7 mm), pedal unguals II (5.8 mm), metatarsals III (30.2 mm), phalanges III-1 (one proximal; 9 mm), phalanges III-2 (8 mm), phalanges III-3 (7 mm), pedal unguals III (5.4, 4.8 mm), metatarsals IV (27.3 mm), phalanges IV-1 (6.1 mm), phalanges IV-2 (5 mm), phalanges IV-3 (4.6, 4.7 mm), phalanges IV-4 (4.9 mm), pedal unguals IV, metatarsals V (one partial; 6.5 mm), pedal claw sheaths, remiges, retrices (Wellnhofer, 1974)
(Opitsch coll.; Maxberg specimen; third specimen; lost) fifth cervical centrum, sixth cervical centrum, seventh cervical centrum, eighth cervical centrum, ninth cervical centrum, tenth cervical centrum, first dorsal centrum, second dorsal centrum, third dorsal centrum, fourth dorsal centrum, fifth dorsal centrum, sixth dorsal centrum, seventh dorsal centrum, eighth dorsal centrum, ninth dorsal centrum, tenth dorsal centrum, eleventh dorsal centrum, twelfth dorsal centrum, thirteenth dorsal vertebra, dorsal rib fragments, gastralia, first sacral vertebra, second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, first caudal centrum, second caudal centrum, third caudal centrum, incomplete scapula, coracoid, incomplete furcula, humeri (one incomplete; 72 mm), radii (63 mm), ulnae (one incomplete; ~62 mm), metacarpals I (~10 mm), distal phalanx I-1, manual unguals I (~12 mm), metacarpals II (~33 mm), phalanges II-1 (19 mm), phalanges II-2 (~22 mm), manual unguals II (~15 mm), metacarpals III (one proximal; 30 mm), phalanges III-1, phalanges III-2, phalanx III-3 (~16 mm), manual unguals III, partial ilium, femur (~58 mm), tibiae (one partial; ~79.5 mm), incomplete fibula, distal tarsal, metatarsal I, metatarsus (one proximal; II ~38 mm, III ~42 mm, IV ~39 mm), phalanx II-1 (~9.5 mm), phalanx II-2 (~10 mm), phalanx III-1 (~11 mm), phalanx III-2 (~10.5 mm), phalanx IV-1, phalanx IV-2, remiges, hindlimb feathers (Heller, 1959)
(TM 6928/29; Haarlem specimen; Teyler specimen; fourth specimen; holotype of Pterodactylus crassipes) (350 day old juvenile) two dorsal centra, dorsal rib fragments, gastralia, incomplete radii, incomplete ulnae, metacarpal I (10 mm), phalanx I-1 (23.3 mm), manual ungual I (9.7 mm), incomplete metacarpal II, distal phalanx II-2, manual ungual II, incomplete metacarpal III (29.4 mm), manual ungual III (10.5 mm), distal pubis, incomplete femora (~54 mm), incomplete tibiae (~80 mm), incomplete fibula, phalanx I-1, pedal ungual I, incomplete metatarsal II, phalanges II-1, phalanges II-2, pedal unguals II, incomplete metatarsal III (~48 mm), phalanges III-1, phalanx III-2, phalanx III-3, pedal unguals III, incomplete metatarsal IV, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, two pedal phalanges, remiges (Ostrom, 1972)
(WDC-CSG-100; Thermopolis specimen; tenth specimen) (260 g, 1 year old juvenile) skull (52.9 mm), sclerotic ring, mandibular fragment, five dentary teeth, partial hyoid, six cervical vertebrae, partial seventh dorsal vertebra, partial eighth dorsal vertebra, partial ninth dorsal vertebra, partial tenth dorsal vertebra, partial eleventh dorsal vertebra, partial twelfth dorsal vertebra, partial thirteenth dorsal vertebra, dorsal ribs, gastralia, first sacral centrum, second sacral centrum, third sacral centrum, fourth sacral centrum, fifth sacral fragment, first caudal vertebra, second caudal vertebra (3.8 mm), third caudal vertebra (4.2 mm), fourth caudal vertebra (4.2 mm), fifth caudal vertebra (5.4 mm), sixth caudal vertebra (6.5 mm), seventh caudal vertebra (7.9 mm), eighth caudal vertebra (9.5 mm), ninth caudal vertebra, tenth caudal vertebra (~10 mm), eleventh caudal vertebra (11.1 mm), twelfth caudal vertebra (10.9 mm), thirteenth caudal vertebra (10.9 mm), fourteenth caudal vertebra (10.6 mm), fifteenth caudal vertebra (10.6 mm), sixteenth caudal vertebra (10.1 mm), seventeenth caudal vertebra (9.1 mm), eighteenth caudal vertebra (9.1 mm), nineteenth caudal vertebra, partial twentieth caudal vertebra, chevrons, scapulae (35 mm), coracoids, furcula, humeri (one proximal; 56.9), radii, ulnae (50.9 mm), semilunate carpal, metacarpals I (6.6 mm), phalanges I-1 (19.5 mm), manual unguals I, metacarpals II (23.5 mm), phalanges II-1 (12.8 mm), phalanges II-2 (18.6 mm), manual unguals II, metacarpals III (22 mm), phalanges III-1 (4.8 mm), phalanges III-2 (4.2 mm), phalanges III-3 (12.9 mm), manual ungual III, manual claw sheaths, partial ilium, pubes, ischium, femora (one incomplete; 50.3 mm), tibiae (one incomplete; 74.6 mm), fibula, astragali, calcaneum, metatarsals I, phalanges I-1 (6.1 mm), pedal unguals I, metatarsals II (35.1 mm), phalanges II-1 (10.6 mm), phalanges II-2 (one proximal; 8.8 mm), pedal ungual II, metatarsals III (39.6 mm), phalanges III-1 (one proximal; 10.8 mm), phalanx III-2 (9.6 mm), phalanx III-3 (7.8 mm), pedal ungual III, metatarsals IV (36.3 mm), phalanges IV-1 (7.5 mm), phalanges IV-2 (one proximal; 6.6 mm), phalanx IV-3 (5.6 mm), phalanx IV-4 (5.6 mm), pedal ungual IV, pedal claw sheaths, remiges, retrices (Mayr et al., 2005)
(Pohl coll; on long term loan to BSP; eleventh specimen) premaxillae, jugal, dentaries, partial ?splenial, incomplete ?surangular, ?articular, axis, third cervical vertebra, fourth cervical vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh cervical vertebra, eighth cervical vertebra, ninth cervical vertebra, tenth cervical vertebra, cervical ribs, first dorsal vertebra, second dorsal vertebra, third dorsal vertebra, fourth dorsal vertebra, fifth dorsal vertebra, sixth dorsal vertebra, seventh dorsal vertebra, eighth dorsal vertebra, ninth dorsal vertebra, tenth dorsal vertebra, eleventh dorsal vertebra, twelfth dorsal vertebra, thirteenth dorsal vertebra, dorsal ribs, gastralia, partial sacrum, first caudal vertebra, second caudal vertebra, third caudal vertebra, fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra, eighth caudal vertebra, ninthtenth caudal vertebra, eleventh caudal vertebra, twelfth caudal vertebra, thirteenth caudal vertebra, fourteenth caudal vertebra, fifteenth caudal vertebra, sixteenth caudal vertebra, seventeenth caudal vertebra, eighteenth caudal vertebra, nineteenth caudal vertebra, twentieth caudal vertebra, twenty-first caudal vertebra, chevrons, scapula (44.4 mm), incomplete coracoid (13.3 mm), partial furcula, incomplete humerus (65.6 mm), radius (~62 mm), ulna (~62.5 mm), ulnare, semilunate carpal, partial metacarpal I (~9.9 mm), phalanx I-1 (23.3 mm), manual ungual I, metacarpal II (~31.5 mm), phalanx II-1 (18.6 mm), phalanx II-2 (19.6 mm), manual ungual II, metacarpal III (~31.5 mm), phalanx III-1 (6.4 mm), phalanx III-2 (5.3 mm), phalanx III-3 (~12.3 mm), manual ungual III, manual claw sheaths, incomplete ilium (~37.1 mm), pubes (52.2 mm), ischium (23.3 mm), femora (one distal; 55.3 mm), tibiae (76.3 mm), partial fibulae, astragali, metatarsals I (~7.1 mm), phalanges I-1 (7.9, 7.4 mm), pedal unguals I, metatarsals II (36.8, 38.4 mm), phalanges II-1 (9.9, 9.9 mm), phalanges II-2 (9.7, 9.5 mm), pedal unguals II, metatarsals III (40.3, 41.4 mm), phalanges III-1 (11.6, 11.2 mm), phalanges III-2 (10 mm), phalanges III-3 (8.8 mm), pedal unguals III, metatarsal IV (~37.9 mm), phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal unguals IV, pedal claw sheaths, body feathers, remiges, retrices (Ravasz, online 2011; described by Foth et al., 2014)
Early Tithonian, Late Jurassic
Mörnsheim Formation, Germany

?(private coll.; Daiting specimen; eighth specimen) (320 day old juvenile) incomplete skull, mandible, vertebral fragments, scapulae, coracoids, furcula, humeri (one incomplete), radii (one partial), ulna, semilunate carpal, carpal, metacarpal I, phalanx I-1, manual ungual I fragment, incomplete metacarpals II, incomplete metacarpals III (Mauser, 1997)
Haarlem specimen- Meyer (1857) named TM 6928/29 Pterodactylus (Rhamphorhynchus) crassipes, decribing it in detail in 1860. The only other author to consider the specimen was Wellnhofer (1970), who believed it was closest to Scaphognathus, making it S. crassipes. Ostrom (1970) identified it as an Archaeopteryx specimen many years later. He later described it in more detail in 1972(b), noting that since crassipes has priority over lithographica chronologically, the species should technically be called Archaeopteryx crassipes. However, he petitioned the ICZN that same year (a) to conserve the name Archaeopteryx lithographica, which was upheld by the ICZN in 1977 as opinion #1070 (Melville, 1977).
London specimen and feather- Meyer (1861a) first mentioned and described the feather discovered in 1860, but did not name it. He later (1861b) referred to the feather and mentioned the then undescribed London specimen discovered that year, stating that "For the denomination of the animal I consider the term Archaeopteryx lithographica as appropriate", but exactly which specimen (if not both) he considered "the animal" is ambiguous. The title suggests the feather is the holotype, but this was written by an anonymous editor. In his later (1862a) paper, he indicates the name Archaeopteryx lithographica was meant to be tied to the feather, making it the holotype ("The fossil feather presented by me may come from a similar animal, for which I have chosen the denomination Archaeopteryx lithographica"). This was misunderstood by many subsequent authors, including de Beer (1954), who have viewed the London specimen as the holotype instead. Wagner (1962a) described the London specimen as a new genus of pterosaur- Griphosaurus, being unaware of Meyer's 1861b paper. While the paper was dated 1861, it wasn't published until January 20th, 1862. Woodward (1962) used the name Archaeopteryx lithographica, but stated Owen would describe the London species under the name Griphornis longicaudatus. A footnote indicates Owen had decided to retain the name Archaeopteryx though, as indeed did happen in his 1863 paper. More confusingly, Woodward uses the name "Griphosaurus problematicus Wagner, 1861" in the plate label for the London specimen, though Wagner never used a species name in his 1862 ("1861") publication. Owen (1863a) made the London specimen the holotype of his new species Archaeopteryx macrura (misspelled macrurus in his 1863a publication, but corrected in 1863b), since he considered its feathers different from the A. lithographica holotype. Several later authors followed Owen's usage (Dames, 1884; Lambrecht, 1933). The new combination Griphosaurus longicaudatus has been listed as deriving from Owen (1862), but Buhler and Bock (2002) indicate this was a mistaken attribution by Brodkorb (1963). Petronievics (1921) used the name Archaeopteryx oweni for the London specimen without justification, so it is clearly a junior synonym. In 1960, Swinton petitioned the ICZN to place Archaeopteryx lithographica on the Official List of Generic/Specific Names in Zoology, and to add Griphosaurus, Griphornis longicaudatus, Griphosaurus problematicus, Archaeopteryx macrurus and Archaeopteryx oweni to the Official Index of Rejected and Invalid Generic/Specific Names in Zoology, which was upheld by Riley and China in 1961 as Opinion #607. Bock and Buhler (2007) have recently petitioned the ICZN to make the London specimen the neotype of Archaeopteryx lithographica, since authors have interpreted Meyer's intent in different ways, and nearly all references have based the taxon on the more diagnostic skeleton as opposed to the feather. The issue was decided by the ICZN in 2011 as Opinion 2283 in favor of making the London specimen the neotype. The feather was recently redescribed by Griffiths (1996), who noted it differed from the London and Berlin specimens in being smaller, broader and more asymmetrical. He proposed that both taphonomic and taxonomic explanations were possible, and his analysis indicates the feather cannot be definitively referred to Archaeopteryx lithographica in any case. Benton and Gower (2002) reveal Walker had written a letter in 1985 also wondering about the possibility the feather was taxonomically distinct from the skeletons, though it was never published. The London specimen was most recently described in detail by de Beer (1954) and reinterpreted as a retrix by Foth and Rauhut, 2013).
Berlin specimen- The Berlin specimen was discovered in 1877 and variously regarded as conspecific with the London specimen (Dames, 1884), or different due to size (Seeley, 1881). Later, Dames (1897) made the holotype of a new species- Archaeopteryx siemensii due to dental and pelvic characters. Subsequently, Petronievics (as a footnote in Petronievics and Woodward, 1917) separated it further as a new genus- Archaeornis. This was due to his view the expanded calcitic mass of the London specimen was not homologous to the pubic boot of the Berlin specimen, that the latter lacked a pubic symphysis, and other unstated pectoral and pelvic differences. Additional differences later provided by Petronievics (1921, 1925) include teeth with a circular cross section, proximal carpals ossified, metacarpal III with cylindrical section, unfused scapulocoracoid, narrow coracoid, unfused tibiotarsus, pubis and ischium at a greater angle, obturator foramen absent in pubis, straight ischium, and ischium poorly ossified distally. Petronievics later (1927, 1950) went so far as to place Archaeopteryx as a pan-paleognath and Archaeornis as a pan-neognath. Nopcsa (1923) noted most of these characters were preservational (carpal number; pubic foot size; ischial shape) or ontogenetic (length of pubic symphysis; ischial ossification; tibiotarsal fusion), while others were misinterpretations (tooth cross section; scapulocoracoid fusion; pubic angle; obturator foramen). He and de Beer (1954) synonymized it with A. lithographica, which has been the consensus until recently. In 2002, Elzanowski reinstated Archaeopteryx siemensii based on the smaller size, lack of a cuppedicus fossa on the ilium, lack of a ventral hook on the ilial preacetabular process, and pedal unguals without flexor tubercles. Senter and Robins (2003) disagreed, finding flexor tubercles in all Archaeopteryx specimens, and believing the ilial features to become more developed with age. Mayr et al. (2007) confirmed the flexor tubercles are more poorly developed and noted the metatarsus was more slender, but did not comment on ilial morphology.
Maxberg Specimen- The Maxberg specimen was discovered in 1956 and described in 1959 by Heller. It was privately owned by Opitsch, though on display at the Maxberg Museum from 1959-1982. Unfortunately, when Opitsch died in 1991, the specimen could not be found and was seemingly stolen (Abbott, 1992). Mayr et al. (2007) assigned it to A. lithographica (as opposed to A. siemensii) due to its robust metatarsus.
Eichstatt specimen- The Eichstatt specimen was discovered in 1951 and originally identified as a juvenile Compsognathus. This was initially described by Mayr (1973) as perhaps a new species of Archaeopteryx, and later in detail by Wellnhofer (1974) as a juvenile A. lithographica. Howgate (1984) separated it from the other specimens then known as a new species, Archaeopteryx recurva. This was based on the small size, recurved teeth, supposedly absent furcula, more vertical pubis, short pubic symphysis, elongate tibia (1.42 times femoral length compared to 1.30-1.38), elongate metatarsus (1.67 times femoral length compared to 1.43-1.47) and unfused metatarsus. He later used these characters to separate it further as a new genus- Jurapteryx. However, almost all later authors have believed it to be a juvenile specimen of Archaeopteryx lithographica (Paul, 1988; Wellnhofer, 1992), with the furcula missing due to taphonomy and the pubes of the London and Berlin specimens rotated too far posteriorly. Houck et al. (1990) determined the limb proportions of Archaeopteryx specimens were consistant with allometric variation that would be expected due to ontogeny, which has been confirmed for subsequent specimens by Senter and Robins (2003) and Bennett (2008). Christiansen's (2006) allometric study concluded the data supported multiple species at least as well as it did a single species, but his rationale was flawed (Bennett, 2008). Elzanowski (2002) could not confirm separation of the Eichstatt specimen as a distinct species, while Senter and Robins (2003) noted theropods such as Coelophysis decrease curvature of teeth with ontogeny, suggesting the same explanation for the Eichstatt specimen's teeth.
Solnhofen specimen- The Solnhofen specimen was discovered in a private collection in 1987 and initially identified as a Compsognathus until it was examined in 1988 by Wellnhofer and described by him that year as a new specimen of Archaeopteryx lithographica. Longer descriptions appeared later in 1988 and in 1992. In 2001, Elzanowski separated the specimen as a new taxon - Wellnhoferia grandis. This was based on the large size, short tail as reconstructed (~16-17 vertebrae), unfused scapulocoracoid, shorter manual ungual I compared to phalanx I-1 (33%), manual phalanges I-1 and II-2 deeper, manual phalanges III-1 and III-2 sutured, more retroverted pubis (~128 degrees), metatarsals II and IV subequal in length, pedal phalanx II-2 longer than II-1, short pedal digit IV with only four phalanges, pedal ungual IV longest phalanx in digit, and pedal ungual IV straight with flexor tubercle widely separated from its base. In 2002, he added a proximally tapering metatarsal II to the diagnosis. Senter and Robins (2003) agree it is distinct, and Mayr et al. (2007) agree it is distinct from the Berlin and Munich specimens, but disputed differences between it and the London specimen (synonymizing it with A. lithographica). In particular, they note the proportions of manual digit I phalanges and number of phalanges in pedal digit IV are not preserved in the London specimen, and the tail length is uncertain in the Solnhofen specimen (it was estimated to be short by Elzanowski due to the rapid decrease in central length distally). The specimens are also both larger than other specimens and share additional characters (premaxillary teeth with constricted crowns; similar limb proportions; stout metatarsus; well developed flexor tubercles on pedal unguals). However, the London specimen has a fused scapulocoracoid, pedal phalanx II-2 equal in length to II-1, a more elongate pedal digit IV, and a curved pedal ungual IV.
Munich specimen- The next specimen was discovered in 1992 and first called the Solnhofen-Aktien-Verein specimen, then later the Munich specimen. It was described in 1993 as a new species of Archaeopteryx, A. bavarica. This was based on the small size, twelve dentary teeth, dentary interdental plates, ossified sternum, elongate tibia (1.48 times femoral length), hindlimb elongate compared to humerus (3.56 times). Elzanowski (2002) added further distinguishing characters- anterior dentary tooth crowns compressed; third and fourth cervical neural spines tall, equaling about a third of vertebral height; ulna elongate compared to humerus (96%); ilium lacking ventral hook on preacetabular process; no cuppedicus fossa on ilium; pedal unguals lack flexor tubercles. Senter and Robins (2003) determined the tibial, hindlimb and ulnar lengths were all explainable by allometry, believed the ilial features could be absent due to ontogeny, noted tooth compression could be too (as in tyrannosaurids), and stated pedal ungual flexor tubercles are actually present. Wellnhofer and Tischlinger (2004) determined the supposed sternum of the Munich specimen is really a coracoid. Mayr et al. (2007) noted their new specimen is intermediate between the Munich and Berlin specimens in size, hindlimb and ulnar proportions, while its tibia is longer than the Munich specimen. Considering the misidentified sternum, and that the ilial and pedal ungual characters are supposedly shared with the Berlin specimen, they synonymized A. bavarica with A. siemensii.
New specimens- The eighth or Daiting specimen is in a private collection and was discovered in 1997. It was originally noted by Mauser (1997) in a brief article and has been described by Tischlinger (2009). As it derives from a younger formation, it may be distinct. Kundrat et al. (2014) suggested fused internasal and interfrontal contacts and "numerous other cranial features" suggested this may be a separate species from the Eichstatt and Thermopolis specimens, but the details have yet to be published.
The ninth specimen was initially announced by Roper (2004) after it was collected that year. It is the oldest specimen and has immature bone grain. Wellnhofer and Roper (2005) described it in detail, assigning it to A. lithographica instead of A. bavarica (based on ulnar proportions).
The Thermopolis specimen was originally recognized in 2001 and first briefly described in 2005 (Mayr, 2005; Mayr et al., 2005) before being described in detail by Mayr et al. (2007). Though initially only assigned to Archaeopteryx sp. (Mayr et al., 2005), they later assigned it to A. siemensii, in which they also include the Munich specimen. This was based on small size, slender metatarsus, poorly developed pedal ungual flexor tubercles, as well as characters differing from the Solnhofen specimen (long manual ungual I; metatarsals II and IV not subequal; pedal digit IV with five phalanges; pedal ungual IV shorter than phalanx IV-1). They further note that the ischium exhibits a different morphology than the London specimen, which added evidence to separate siemensii from lithographica.
An eleventh specimen was announced at the Munich Show - Mineralientage München in 2011 (Ravasz, online 2011). The skeleton is essentially complete except for most of the skull and one pectoral girdle and arm. Foth and Rauhut (2013) describe the feathers in an abstract, and officially in Foth et al. (2014). Foth et al. only refer the specimen to Archaeopteryx sp. noting the taxonomic controversy surrounding the genus.
Resolving the species problem- As can be seen from the above discussions, recent papers have placed the known specimens in one (Paul, 2002), two (Senter and Robins, 2004; Mayr et al., 2007) or four (Elzanowski, 2002) species, often based on similar characters. These will be examined below to determine how many species are based on good evidence.
Size is not evidence of multiple species, as no specimen is obviously adult, and young theropods (including basal birds) were precocial in regard to their ossification timing (e.g. Scipionyx, juvenile Yixian enantiornithines). The latter disproves Howgate's (1984) suggestion that well ossified elements indicate the Eichstatt specimen is an adult. More recently, Erickson et al. (2009) have analyzed the histology of the Munich specimen and noted this and other specimens (including the Solnhofen specimen) show fibrous surface texture with long striae on long bones typical of young individuals.
Tooth recurvature is polymorphic in every specimen (Howgate, 1984). In the London specimen, the third premaxillary tooth and maxillary teeth 1, 3 and 6 are straight, but an isolated premaxillary tooth is recurved. In the Berlin specimen, the first premaxillary tooth, and maxillary teeth 1 and 6 are straight, but premaxillary teeth 2-4 and maxillary teeth 1 and 3-5 are recurved. In the Eichstatt specimen, maxillary teeth 3 and 9, and dentary teeth 2, 4-6 and 10-11 are straight, but all premaxillary teeth, maxillary teeth 1-2 and 4-6, and dentary tooth 7 are recurved. In the Thermopolis specimen, premaxillary teeth 1-2 are straight, but premaxillary teeth 3-4 and maxillary teeth 4-8 are recurved. In the Solnhofen specimen, premaxillary teeth 1-2 and 4, maxillary teeth 4-7 and perhaps four dentary teeth (4-7?) are straight, but premaxillary tooth 3 and maxillary teeth 2 and 3 are recurved. In the Daiting specimen, three maxillary teeth and two dentary teeth are straight, while one dentary tooth is recurved. In the 11th specimen, premaxillary teeth 1-2 and most dentary teeth are straight but premaxillary teeth 3-4 and at least one dentary tooth are recurved. The narrow tips of the Eichstatt specimen's teeth are directly due to the more acute angle of a recurved crown, and some of its teeth (e.g. second premaxillary tooth) have apical wear facets as in the London specimen. The London's and Munich's specimens teeth appear flatter because they are exposed in lingual view, unlike the Berlin specimen. The presence of one less dentary tooth in the Munich specimen compared to the Eichstatt specimen is within the normal range of interspecific variation in theropods (e.g. Currie, 2003). The presence of interdental plates in the Munich specimen is probably a misinterpretation (Martin and Stewart, 1999), so it it similar to the London and 11th specimens in this regard. So the only difference is in the frequency of tooth recurvature, which is actually less in the Eichstatt specimen than the Berlin and Thermopolis specimens, while the sample size of the London specimen (four teeth) is too low for useful comparison. A large sample of Saurornitholestes teeth shows generally decreasing curvature with increasing size, which shows curvature could be ontogenetic as described by Howgate (1984) for Varanus and Senter and Robins (2004) for Coelophysis. There are a number of cranial differences between the Berlin and Eichstatt specimens which may be due to ontogeny (the Berlin specimen has a more convex ventral maxillary edge, differently sized and placed maxillary fenestrae, deeper dentary; similar to ontogenetic changes in tyrannosaurids), though if the subnarial nasal process being absent isn't preservational, it may be of taxonomic importance. The convexity doesn't seem to be shared by the Solnhofen or Thermopolis specimens. The Thermopolis specimen has a nasal subnarial process and maxillary fenestrae that resemble the Eichstatt specimen's more, but the latter are still differently shaped.
The neural spines of cervical vertebrae three and four are comparable in height in the Eichstatt (3rd 28% of vertebral height; 4th 28%), Berlin (3rd 29%; 4th 28%) and Munich (3rd 29%; 4th 30%) specimens. While it's true the tail of the Solnhofen specimen is broken through the fifteenth caudal, and thus the total number of vertebrae is uncertain, Elzanowski (2001) based his lower estimate on the sharp decrease in centrum length between the thirteenth and fourteenth caudal (the latter is 73% of the former). This compares to 95% in the London specimen, 92% in the Munich specimen, ~91% in the Berlin specimen, 100% in the Eichstatt specimen, 97% in the Thermopolis specimen and ~97% in the 11th specimen. Contrary to Elzanowski though, the fifteenth caudal is not necessarily as short, since only the proximal half is preserved. Other Archaeopteryx specimens can have isolated shorter vertebrae before the tail tip, for instance caudal 17 of the Munich specimen is 74% as long as caudal 16, even though caudals 18 and 19 are 88% and 105% as long as caudal 16. While Elzanowski argues the sudden thinness of these last two vertebrae shows they were near the tail tip, Wellnhofer (1992) notes the tail is twisted at caudals 12-13 to show the following vertebrae in dorsal aspect. As in the Thermopolis specimen, distal caudal vertebrae are taller than they are wide, explaining the thinness. Thus the tail of the Solnhofen specimen was not necessarily shorter than the others'. One vertebral difference in specimens that does seem real is the height of the dorsal neural spines, which using the twelfth dorsal vertebra for comparison are 28% of vertebral height in the Eichstatt specimen, 26% in the Solnhofen specimen, 38% in the Munich specimen, ~29% in the Berlin specimen, ~29% in the Maxberg specimen and ~38% in the 11th specimen. Also, the Thermopolis specimen has its last dorsal sutured to the sacrum, giving it six sacral vertebrae. This is certainly not the case for the Eichstatt, Maxberg and London specimens, and doesn't seem to be for the Munich specimen either. The Eichstatt specimen seems to lack caudal neural spines, wheras they are present in the Munich, Solnhofen and 11th specimens.
The scapula and coracoid are apparently fused in the London specimen, tightly connected in the Berlin and Maxberg specimens, and more loosely connected in the Eichstatt, Solnhofen, Daiting and 11th specimens. They are also unfused in the Munich and Thermopolis specimens. However, scapulocoracoid fusion is variable within other taxa as well, including Struthiomimus, Dromiceiomimus and Caudipteryx. Maniraptoran coracoids are complex bones, which makes comparing their shapes difficult. For instance, the right coracoid of the Thermopolis specimen and left coracoid of the London specimen (as illustrated by Ostrom, 1976) appear to be short, but that's probably because their proximal portion is bent into the sediment. The proximal portion is illustrated in the London specimen by Petronievics and Woodward (1917), and also makes the coracoid elongate in the Munich specimen, while the bend can be observed in the lateral views of the Solnhofen and Thermopolis left coracoids. The medial margin of the London specimen's coracoid has two notches which are not seen in the Munich or Thermopolis specimens. The absence of a furcula in the Eichstatt specimen is near certainly taphonomic, while the supposed sternum in the Munich specimen is a coracoid.
Ulnohumeral ratios vary between ~86% (Maxberg), 87% (Berlin), ~87% (Solnhofen), 88% (Eichstatt and ninth), 89% (Thermopolis), 90% (London), ~92% (Daiting), ~95% (11th) and ~96% (Munich). While this a large amount of variation, is is continuous and also known in Sapeornis. All specimens probably had four carpals (radiale, ulnare, semilunate carpal, distal carpal III), though these are easily lost. In particular, the London specimen is seemingly missing proximal carpals, the Eichstatt specimen lacks the ulnare on the right hand (the bone labeled as an ulnare is probably distal carpal III), the left manus of the Munich specimen lacks the radiale, only the semilunates are visible in the Thermopolis specimen, ninth and Daiting specimens, and the Maxberg specimen seems to lack preserved carpals. Contrary to Elzanowski (2001), manual ungual I is not short compared to phalanx I-1 in the Solnhofen specimen. However, manual phalanx I-1 of the Solnhofen specimen is 1.39 times as long as phalanx II-1, compared to 1.36 times in the ninth specimen, 1.60 times in the Munich specimen, 1.32 times in the Berlin specimen, 1.53 times in the Eichstatt specimen, 1.52 times in the Thermopolis specimen and 1.25 times in the 11th specimen. Similar variation is known in other coelurosaurs however (Sapeornis, Dromiceiomimus, Gorgosaurus). Elzanowski (2001) noted manual phalanx I-1 is more robust in the Solnhofen and Haarlem specimens (minimum height 8.4% and 8.2% of phalanx length respectively compared to the Berlin (6%), Eichstatt (5.84%) and Munich (5.75%) specimens, and this is also true compared to the ninth (6.56%), Thermopolis (7.4%) and 11th (7.0%) specimens. Yet the latter three also close the gap in ratios, making them seem less important for dividing specimens. Similarly, the Thermopolis specimen (~8.1%) fills the gap between the Solnhofen (8.9%) and 11th (8.7%) on one hand, and the Berlin (6.2%), Eichstatt (6.9%) and Berlin (6.2%) specimens on the other when it comes to robusticity of manual phalanx II-2. The cross section of metacarpal III was said to distinguish the London and Berlin specimens, but this has not been studied in further specimens. Metacarpal III is more bowed with an intermetacarpal gap in the Solnhofen, Munich, Thermopolis and ninth specimens compared to the Berlin, Eichstatt, Daiting and 11th specimens, but this may be due to its orientation. Manual phalanges III-1 and III-2 are sutured in the Solnhofen specimen (as in Jinfengopteryx and the Didactylornis type), but not in the Berlin, Maxberg, Eichstatt, Munich, ninth and Thermopolis specimens. The ratio between phalanges III-2 and III-1 varies between 66% (Berlin), ~69% (Maxberg), 71% (Eichstatt), 79% (ninth), 81% (Solnhofen), 83% (11th), 86% (Munich) and 88% (Thermopolis). While this is quite a range, it is also gradational and seen in some other taxa (Struthiomimus, Dromiceiomimus).
The Eichstatt, Solnhofen, Berlin and possibly the 11th specimens have an unexpanded preacetabular processes, the London and probably the Munich and Thermopolis specimens have ventrally expanded processes. Senter and Robins (2003) suggested this could be due to ontogeny, but juvenile tyrannosaurids, Juravenator, Gallimimus, therizinosauroids, Microvenator, Bambiraptor and Scansoriopteryx all have expanded preacetabular processes, though the subadult Yangchuanosaurus shangyouensis holotype lacks one while the larger Y. magnus holotype has one. The preacetabular process varies in length between specimens, from 54% of pubic peduncle plus acetabulum length in the Solnhofen specimen to 89% (Eichstatt), ~111% (Munich), 120% (London), ~133% (11th) and 160% (Berlin). Elzanowski (2002) claimed the Berlin and Munich specimens lack an m. cuppedicus fossa on their ilia, unlike the London specimen, but such a fossa is clearly visible in the Berlin specimen (Ostrom, 1976- figure 20) while the Munich specimen seems to not preserve a lateral surface (Wellnhofer, 1993- plate 9). The Eichstatt specimen's ilium is only visible in medial view, while the Solnhofen specimen is too poorly preserved to tell. The London specimen differs from the Berlin, Eichstatt, Munich and Solnhofen specimens in having a dorsally concave ilium. The pubic angle of Archaeopteryx has been quite controversial, but is articulated at 3 degrees posterior to vertical in the Munich specimen. The pubis is disarticulated in the London, Berlin, Eichstatt, Solnhofen, Thermopolis and 11th specimens, so its angle cannot be used to distinguish species. The London and Thermopolis specimens have posterior pubic boots partially replaced by calcite (originally from cartilage?), while the Eichstatt, Munich, Berlin and 11th specimens seem to have more ossified pubic boots, but this could be ontogenetic. The London specimen differs from the Haarlem, Berlin and Eichstatt specimens (Ostrom, 1976) in having a transversely expanded pubic boot. The length of the pubic apron varies between 36% (Berlin), 39% (Solnhofen), 40% (Eichstatt), ~46% (London) and ~47% (Thermopolis), but may be overestimated in the last two due to their incompletely ossified distal ends. The obturator foramen identified by Petronievics in the London specimen is a pneumatic fossa (Christiansen and Bonde, 2000), and whether it is present in other specimens is uncertain due to a lack of posterior pubic exposure. The ischia of specimens differ a great deal, but this has not been recently and explicitly described. The London specimen has an obturator foramen (unique among maniraptoriforms), while a fossa is present in the Eichstatt and Munich specimen, and the Thermopolis and 11th specimens seemingly lack either. The proximoventral edge of the ischium is convex in the London specimen, unlike the Berlin, Eichstatt, Munich, Thermopolis and 11th specimens. The obturator process projects ventrally in the Munich and Thermopolis specimens, a bit less in the Eichstatt and 11th specimens, and not at all in the London specimen. The distodorsal process (at midlength) varies from a rounded bump in the London specimen and low angularity in the Munich specimen to a large triangular spine in the Solnhofen, 11th and especially Eichstatt specimens, to a large flange with a posterior notch in the Thermopolis specimen. Similarly, the proximodorsal process varies from a low peak (Berlin, Eichstatt, Thermopolis, 11th), to a slender point (Solnhofen), to a massive block-like process (Munich, London). The London specimen's further differs in having a notch proximally, making it rectangular. Ischial variation has not been examined much in other taxa, though Microraptor varies in the angle of the distal obturator process edge, obturator process expansion, shaft depth and ventral convexity proximal to the obturator process. Mirischia famously varies in the presence of an obturator process and notch. Tyrannosaurus varies in obturator process size and orientation, as well as proximodorsal process size, shaft curvature and distal expansion. The differences observed in Archaeopteryx specimens may be due to intraspecific variation as well.
Hindlimb ratios are explainable by allometry (Bennett, 2008), as are the more robust metatarsi of large specimens (Maxberg, Solnhofen) compared to smaller ones (Eichstatt, Munich, Thermopolis, 11th) (compare to juvenile tyrannosaurids vs. adults). Tibiotarsal and tarsometatarsal fusion is controversial in Archaeopteryx. It seems absent in the Eichstatt and Munich specimens. Tibiotarsal and metatarsal fusion are absent in the Thermopolis specimen, though the astragalus and calcaneum could be fused. In the Berlin and London specimens, there is no evidence for metatarsal fusion and at least the ascending process of the astragalus remains unfused to the tibia. Though Ostrom (1976) claimed the distal tarsal in the Maxberg specimen was "at least partially fused" to the metatarsus, he said the same of the Eichstatt specimen which seems to be untrue. Metatarsals II-IV of the Maxberg specimen are indistinguishable proximally and fused as determined by x-rays. The Solnhofen specimen lacks tibiotarsal and tarsometatarsal fusion, but metatarsals II-IV seem to be partially fused proximally. Fusion could be ontogenetic, of course, as the Solnhofen and Maxberg are among the largest specimens. The metatarsal II/IV ratio varies between 97% (Thermopolis), ~97% (Munich, Maxberg, 11th), 100% (Solnhofen), 104% (Eichstatt), and ~108% (Berlin). Tyrannosaurus has a similar variation (91-103%), and that of Dromiceiomimus is slightly less (90-97%). While Elzanowski (2001) emphasized the equal lengths in the Solnhofen specimen, it is intermediate between the other specimens and thus not an outlier. The proximally tapering second metatarsal in the right foot of the Solnhofen specimen is probably due to distortion as it is not present in the left foot. The phalanx II-2/II-1 ratio varies between 83% (Thermopolis), 85% (Berlin), 96-98% (11th), ~99% (Eichstatt), ~100% (Munich), 100% (London), 104% (Solnhofen) and ~105% (Maxberg), so would seem to distinguish the Berlin+Thermopolis specimens, as opposed to the Solnhofen specimen (contra Elzanowski, 2001). Ratios in Velociraptor are more variable (103-129%), showing this could be intraspecific variation. Pedal digit IV has four phalanges in the Solnhofen specimen (as in the Didactylornis type), but five phalanges in the Berlin, Eichstatt, Munich, Thermopolis and 11th specimens. This leads to the fourth digit being shorter in the Solnhofen specimen. Though the London specimen has an unknown number of phalanges in digit IV, it is long as in specimens with five phalanges. Pedal ungual IV is longer than phalanx IV-1 in the Solnhofen specimen, but not the Berlin, Eichstatt, Munich and Thermopolis specimens. Pedal ungual IV of the Solnhofen specimen is also distinct from the London, Berlin, Eichstatt, Munich, Thermopolis and 11th specimens in being straight ventrally. Variation in pedal ungual curvature has been reported in Deinonychus too (Ostrom, 1969). Pedal flexor tubercles are large in the London (I, II, III and IV) and Solnhofen (I and III but not IV) specimens, but small (though not absent) in the Berlin, Eichstatt, Munich, Thermopolis and 11th specimens. If Zhongornis is a juvenile Confuciusornis, it would provide an example of young specimens having smaller pedal flexor tubercles than adults.
When the characters above are entered into a matrix with Shenzhouraptor and Anchiornis as outgroups to establish polarity, the London+Munich specimens branch off first due to preacetabular length (also in the 11th), obturator area of ischium at least depressed (also in Eichstatt) and large proximodorsal ischial process. Other specimens are united with Shenzhouraptor by the low dorsal neural spines (not in the 11th specimen) and large distodorsal ischial process. The Berlin, Eichstatt, Thermopolis and 11th specimens are united by non-enlarged pedal flexor tubercles (also in Munich), while the Maxburg, Solnhofen and Shenzhouraptor are united by metatarsal fusion. The Solnhofen, ninth and Shenzhouraptor are united by a short manual phalanx I-1 (also in the Berlin specimen and some Anchiornis) and pedal ungual IV longer than IV-1 (also in some Anchiornis). The fact most of these characters are homoplasious shows that there is little evidence to subdivide the genus into species containing more than one individual, despite individual Archaeopteryx specimens (particularily the London and Solnhofen specimens) having several unique features. The choices are similar to that entertained for Microraptor on this site, either several species each represented by a single specimen, or one species which is variable in morphology. The latter more conservative approach is taken here, especially considering the fact no specimens are adult.
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Aurornis Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013
A. xui Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013
Oxfordian, Late Jurassic
Tiaojishan Formation, Liaoning, China

Holotype- (YFGP-T5198) (510 mm adult) skull (57 mm), mandibles, seven cervical vertebrae (series 62 mm), cervical ribs, eleven dorsal vertebrae (series 97 mm), dorsal ribs, synsacrum (30 mm), about thirty caudal vertebrae (series 265 mm), chevrons, scapulae (36.6 mm), coracoid, furcula, humeri (58 mm), radii, ulnae (57 mm), radiale, ulnare, semilunate carpal, metacarpal I (12 mm), phalanx I-1 (27 mm), manual ungual I, metacarpals II (34 mm), phalanx II-1 (14.5 mm), incomplete phalanx II-2, metacarpals III (34.5 mm), phalanx III-1, phalanx III-2, phalanx III-3, incomplete manual ungual III, ilia (34.8 mm), pubes (55 mm), ischia, femora (66 mm), tibiotarsi (90.5 mm), partial metatarsal I, phalanx I-1, pedal ungual I, metatarsi (44 mm), phalanges II-1 (7 mm), phalanx II-2 (9 mm), pedal ungual II, phalanges III-1 (12 mm), phalanx III-2 (6.5 mm), phalanx III-3 (6 mm), pedal ungual III (7.5 mm), phalanges IV-1, phalanx IV-2, phalanx IV-3 (5 mm), phalanx IV-4 (5 mm), pedal ungual IV (7 mm), body feathers
Diagnosis- (modified after Godefroit et al., 2013) manual phalanx I-1 distinctly more robust than radius; robust postacetabular process of ilium not markedly deflected ventrally and with horizontal dorsal margin; distal end of ischium dorsoventrally expanded and formed by hook-like ventral process delimiting a prominent distal obturator notch and by a longer dorsal distal process.
Other diagnoses- Godefroit et al. also list "metatarsal I gracile and elongate (about 30% of metatarsal III length)", but this is erroneous (see below).
Comments- The identification of some elements by Godefroit et al. (2013) is questionable. Instead of the surangular and angular being equal in depth as reconstructed, there is a suture showing the angular was much shallower as is usual for maniraptorans. The third manual digit is reconstructed as having two elongate proximal phalanges and a partially preserved third phalanx that would almost certainly make it longer than digit II. While the poor preservation and photo quality make any identification uncertain, there is a lateral bend halfway through and a short medial concavity that would support their phalanx III-1 being both III-1 and III-2. Thus their III-2 would be III-3, and their III-3 fragment would be most of ungual III, resembling the proportions of other basal paravians. Finally, metatarsal I is shown as being a third as long as III and untapered proximally, unlike any theropod. This apparent structure is formed by parts of the main metatarsal shafts before their surface is broken away more proximally. There does seem to be a small fragment of metatarsal I conntected to phalanx I-1.
The holotype was acquired from a fossil dealer. The authors resolved Aurornis as a basal avialan using a reduced version of Cau's matrix, similar to Lee et al.'s (2014) later iteration of this matrix. Brusatte et al. (2014) found it to be a basal troodontid, however. All of these trees had the genus closely related to Eosinopteryx and Anchiornis, which are tentatively placed as archaeopterygids here.
References- Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013. A Jurassic avialan dinosaur from China resolves the early phylogenetic history of birds. Nature. 498, 359-362.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.

Eosinopteryx Godefroit, Demuynck, Dyke, Hu, Escuillie and Claeys, 2013
E. brevipenna Godefroit, Demuynck, Dyke, Hu, Escuillie and Claeys, 2013
Oxfordian, Late Jurassic
Tiaojishan Formation, Liaoning, China

Holotype- (YFGP-T5197) (subadult) skull (43.2 mm), mandibles (40.2 mm), seven cervical vertebrae (series 39.6 mm), cervical ribs, dorsal vertebrae (series, 57.9 mm), dorsal ribs, gastralia, partial synsacrum (25.1 mm), caudal vertebrae 1-3 (~5.1 mm), fourth caudal vertebra (5.7 mm), fifth caudal vertebra (5.6 mm), sixth caudal vertebra (5.8 mm), seventh caudal vertebra (6.4 mm), eighth caudal vertebra (6.4 mm), ninth caudal vertebra (6.4 mm), tenth caudal vertebra (7.6 mm), eleventh caudal vertebra (9.6 mm), twelfth caudal vertebra (9.6 mm), thirteenth caudal vertebra (8.8 mm), fourteenth caudal vertebra (8 mm), fifteenth caudal vertebra (7.6 mm), sixteenth caudal vertebra (8 mm), seventeenth caudal vertebra (8 mm), eighteenth caudal vertebra (7.4 mm), nineteenth caudal vertebra (6.3 mm), twentieth caudal vertebra (9.2 mm), chevrons, scapulae (23.8 mm), coracoids, partial furcula, humeri (37.9 mm), radii (39.5 mm), ulnae (42 mm), radiale, semilunate carpal, metacarpals I, phalanges I-1 (one incomplete), manual unguals I (one partial), metacarpals II, phalanges II-1, phalanges II-2, manual unguals II, metacarpals III, phalanges III-1, phalanges III-2, phalanges III-3, manual ungual III, ilia (25 mm), incomplete pubis (35 mm), ischia (13.4 mm), femora (48.5 mm), tibiae (69.5 mm), metatarsal I, phalanx I-1, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III (35.5 mm), phalanges III-1 (8.8 mm), phalanges III-2 (7.1 mm), phalanx III-3 (6.5 mm), pedal ungual III (6 mm), metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanx IV-4, pedal ungual IV, body feathers, remiges
Diagnosis- (after Godefroit et al., 2013) short snout, about 82% the length of the orbit; lacrimal with long posterior process participating in about half the length of dorsal margin of orbit and a vestigial anterior process; short tail, composed of 20 caudal vertebrae, 2.7 times length of the femur; chevrons reduced to small rod-like elements below the 8th or 9th caudal; ilium with proportionally long, low and distally tapering postacetabular process (ratio 'length/height at midlength' = 5); pedal unguals shorter than corresponding penultimate phalanges; absence of rectrices (versus other paravians with preserved plumage) and feathers on metatarsus and pes (versus other troodontids with preserved plumage on the hindlimb).
Comments- The holotype was acquired from a fossil dealer. Plumage differences from e.g. Anchiornis are here seen as questionable, as other specimens which should originally possess pennaceous feathers on wings/tail also lack them, presumably due to preservation (Longipteryx holotype, NGMC 91, Epidexipteryx). Godefroit et al. (2013) claimed neurocentral and tibiotarsal fusion indicated a subdult or adult age, but Lefevre et al. (2014) found histology showed it was immature.
The authors resolved Eosinopteryx as a basal troodontid using a version of Senter's TWG matrix. Brusatte et al. (2014) also found Eosinpteryx to be a basal troodontid, while Foth et al. (2014) and Lee et al. (2014) both recovered it as a basal avialan closer to birds than troodontids. All of these trees had the genus closely related to Aurornis and Anchiornis, which are tentatively placed as archaeopterygids here.
References- Godefroit, Demuynck, Dyke, Hu, Escuillie and Claeys, 2013. Reduced plumage and flight ability of a new Jurassic paravian theropod from China. Nature. 498, 359-362.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.
Lee, Cau, Naish and Dyke, 2014. Sustained miniaturization and anatomical innovation in the dinosaurian ancestors of birds. Science. 345(6196), 562-566.
Lefevre, Cau, Hu, Wu, Escuillie and Godefroit, 2014. New basal Avialae from the Jurassic of China. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 167.

Pedopenna Xu and Zhang, 2005
P. daohugouensis Xu and Zhang, 2005
Bathonian, Middle Jurassic
Daohugou Formation, Nei Mongol, China

Holotype- (IVPP V12721) (<1 m) distal tibia, distal fibula, tarsus, metatarsal I, phalanx I-1 (8.6 mm), pedal ungual I (~7.6 mm), metatarsal II (57.6 mm), phalanx II-1 (11.6 mm), phalanx II-2 (14.2 mm), pedal ungual II (~13 mm), metatarsal III (~57.8 mm), phalanx III-1 (~18 mm), phalanx III-2 (~11.3 mm), phalanx III-3 (~11.3 mm), pedal ungual III (10.1 mm), metatarsal IV (57.4 mm), phalanx IV-1 (11.3 mm), phalanx IV-2 (9.9 mm), phalanx IV-3 (6.2 mm), metatarsal V (14.1 mm), feathers, scale impressions, pedal claw sheath
Diagnosis- (from Xu and Zhang, 2005) very slender pedal phalanx I-1 (length/mid-shaft-diameter ratio about 7.2).
Comments- Xu and Zhang (2005) recovered Pedopenna as a paravian in a trichotomy with avialans and deinonychosaurs using a version of the TWG matrix. More recently, Brusatte et al. (2014) found it to be a scansoriopterygid, while Foth et al. (2014) found it to be a basal avialan in a clade with Anchiornis and Eosinopteryx. As the latter are tentatively placed as archaeopterygids here, Pedopenna is also questionably assigned to the family.
References- Xu and Zhang, 2005. A new maniraptoran dinosaur from China with long feathers on the metatarsus. Naturwissenschaften. 92, 173-177.
Brusatte, Lloyd, Wang and Norell, 2014. Gradual assembly of avian body plan culminated in rapid rates of evolution across the dinosaur-bird transition. Current Biology. 24(20), 2386-2392.
Foth, Tischlinger and Rauhut, 2014. New specimen of Archaeopteryx provides insights into the evolution of pennaceous feathers. Nature. 511, 79-82.

Troodontidae Gilmore, 1924
Definition- (Troodon formosus <- Ornithomimus velox, Mononykus olecranus, Therizinosaurus cheloniformes, Oviraptor philoceratops, Velociraptor mongoliensis, Passer domesticus) (modified from Senter et al., 2004)
Other definitions- (Troodon formosus, Saurornithoides mongoliensis, Borogovia gracilicrus, Sinornithoides youngi <- Ornithomimus velox, Oviraptor philoceratops) (Varricchio, 1997)
(Troodon formosus <- Velociraptor mongoliensis) (Makovicky and Norell, 2004; modified from Sereno, 1998)
(Troodon formosus <- Deinonychus antirrhopus, Passer domesticus) (Hu, Hou, Zhang and Xu, 2009)
(Troodon formosus <- Velociraptor mongoliensis, Passer domesticus) (Turner et al., 2012)
(Troodon formosus <- Dromaeosaurus albertensis, Passer domesticus) (Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013)
(Troodon formosus <- Ornithomimus edmontonicus, Velociraptor mongoliensis, Passer domesticus) (Sereno, in press)
= Saurornithoididae Barsbold, 1974
= Troodontidae sensu Sereno, 1998
Definition- (Troodon formosus <- Velociraptor mongoliensis) (modified)
= Troodontoidea Gilmore, 1924 vide Livezey and Zusi, 2007
= Troodontidae sensu Hu, Hou, Zhang and Xu, 2009
Definition- (Troodon formosus <- Deinonychus antirrhopus, Passer domesticus)
= Troodontia Alifanov, 2012
= Troodontidae sensu Turner et al., 2012
Definition- (Troodon formosus <- Velociraptor mongoliensis, Passer domesticus)
= Troodontidae sensu Godefroit, Cau, Hu, Escuillie, Wu and Dyke, 2013
Definition- (Troodon formosus <- Dromaeosaurus albertensis, Passer domesticus)
= Troodontidae sensu Sereno, in press
Definition- (Troodon formosus <- Ornithomimus edmontonicus, Velociraptor mongoliensis, Passer domesticus)
Comments- Sereno's newest (in press) definition differs from his earlier (1998) one which only had Velociraptor as an external specifier, and Senter et al.'s (2004), which had Mononykus, Therizinosaurus and Oviraptor as additional external specifiers. Keeping Oviraptor seems useful, in the case Osmolska and Barsbold (1990), Russell and Dong (1993) or Norell et al. (2001) are correct. I'm not aware of any topology placing Shuvuuia or Therizinosaurus closer to Troodon than the other taxa, but they both seem relatively plausible as troodontid sister taxa. Another specifier that might be useful considering recent discoveries is Archaeopteryx.
No longer troodontids- Currie et al. (1990) said that troodontid teeth reported from the Cedar Mountain Formation by Nelson and Crooks (1987) were more likely velociraptorines because of the serrations are small (12/mm) and elongate.
Although Metcalf and Walker (1994) identified a tooth from the Bathonian Chipping Norton Formation of England as a possible troodontid, it is more likely a dromaeosaurid.
Nessov (1995) cited a troodontid astragalocalcneum from the Bostobe Formation of Kazakhstan, but Averianov and Sues (2007) noted many other maniraptorans have fused astragalocalcanea as well. Kordokova et al. (1996) cited troodontids from the Zhirkindek and Bostobe Formations of Kazakhstan, but these were not mentioned in their later (2001) paper. Averianov (2007) could similarly not confirm the presence of troodontids from either formation.
Nessov (1995) identified CCMGE 484/12457 as a troodontid frontal, which he named Saurornithoides isfarensis. Though they could not locate it, Averianov and Sues (2007) reidentified the specimen as a hadrosaurid prefrontal.
References- Nelson and Crooks, 1987. Stratigraphy and paleontology of the Cedar Mountain Formation (Lower Cretaceous), eastern Emery County, Utah. In Averett (ed.), Paleontology and Geology of the Dinosaur Triangle: Guidebook for 1987 Field Trip. Museum of Western Colorado, Grand Junction. 55-63.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Metcalf and Walker, 1994. A new Bathonian microvertebrate locality in the English Midlands. in Fraser and Sues (eds.). In the Shadow of the Dinosaurs- Mesozoic Small Tetrapods, Cambridge (Cambridge University Press). 322-332.
Nessov, 1995. Dinosaurs of nothern Eurasia: new data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg 1-156.
Kordikova, Gunnell, Polly and Kovrizhinykh, 1996. Late Cretaceous and Paleocene Vertebrate Paleontology and stratigraphy in the Northeastern Aral Sea Region, Kazakstan. Journal of Vertebrate Paleontology. 16(3), 46A.
Kordikova, Polly, Alifanov, Rocek, Gunnell and Averianov, 2001. Small vertebrates from the Late Cretaceous and Early Tertiary of the Northeastern Aral Sea region, Kazakhstan. Journal of Pakeontology. 79(2), 390-400.
Zhao, 2003. The nesting behaviour of troodontid dinosaurs. Vertebrata Palasiatica. 41(2), 157-168.
Makovicky and Norell, 2004. Troodontidae. in Weishampel, Dodson and Osmolska (eds). The Dinosauria, Second Edition. California University Press. 184-195.
Averianov, 2007. Theropod dinosaurs from Late Cretaceous deposits in the northeastern Aral Sea region, Kazakhstan. Cretaceous Research.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.
Livezey and Zusi, 2007. Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion. Zoological Journal of the Linnean Society. 149 (1), 1-95.
Alifanov, 2012. Suborder Theropoda. In Kurochkin and Lopatin (eds.). Fossil vertebrates of Russia and adjacent countries: Fossil reptiles and birds Part 2. GEOS. 169-240.
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and paravian phylogeny. Bulletin of the American Museum of Natural History. 371, 1-206.
Pei, 2014. Early evolution of troodontid dinosaurs based on information from new and old specimens. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 202.

"Paronychodontidae"
Diagnosis- at least one longitudinal ridge found on lingual side of teeth.
Comments- This family has yet to be officially named, but appears in quotes in references like Ruiz-Omenaca et al. (1998).
Reference- Ruiz-Omeñaca, Canudo, Cuenca-Bescós and Amo, 1998. Theropod teeth from the Lower Cretaceous of Galve (Teruel, Spain). Third European Workshop on Vertebrate Paleontology, Maastricht. 62-63.

unnamed paronychodontid (Zinke and Rauhut, 1994)
Early Kimmeridgian, Late Jurassic
Alcobaca Formation, Portugal
Material
- (IPFUB GUI D 1) dentary fragment, three teeth (Zinke and Rauhut, 1994)
(IPFUB GUI D 2) maxillary tooth (1.65 mm) (Zinke and Rauhut, 1994)
(IPFUB GUI D 3) tooth (Zinke and Rauhut, 1994)
(IPFUB GUI D 4-27) twenty-seven teeth (~1.67 mm) (Zinke, 1998)
Comments- IPFUB GUI D 1-3 teeth are recurved with one to two labial ridges and one to four lingual ridges. They have distal serrations which vary in size (6.5/mm in a tooth from GUI D 1; 14/mm in GUI D 2; 31/mm in GUI D 3), though they increase in size basally. GUI D 2 may have a slight basal constriction, and GUI D 3 is not flattened lingually. The mesial carina is unserrated (GUI D 2, GUI D 3), though GUI D 1 has small pits apically that may be worn serrations. Zinke notes all specimens have serrated distal carinae (6-13/mm) and some have serrated mesial carinae (~18/mm). They were identified by Zinke and Rauhut as cf. Paronychodon sp..
References- Zinke and Rauhut, 1994. Small theropods (Dinosauria, Saurischia) from the Upper Jurassic and Lower Cretaceous of the Iberian Peninsula. Berliner geowiss. Abh.. E 13, 163-177.
Zinke, 1998. Small theropod teeth from the Upper Jurassic coal mine of Guimarota (Portugal). Palaontologische Zeischrift. 72(1/2), 179-189.

unnamed paronychodontid (Zinke and Rauhut, 1994)
Early Barremian, Early Cretaceous
Camarillas Formation, Spain
Material
- (JHM POCA-H7) anterior tooth (3.3 mm)
(JHM POCA-H8) lateral tooth (2.08 mm)
Comments- These teeth have 2-3 labial ridges and 3-4 lingual ridges. They lack mesial serrations, and have weak distal serrations (14-16/mm). Distal serrations are rounded and directed slightly apically.
References- Zinke and Rauhut, 1994. Small theropods (Dinosauria, Saurischia) from the Upper Jurassic and Lower Cretaceous of the Iberian Peninsula. Berliner geowiss. Abh.. E 13, 163-177.
Ruiz-Omenaca, 2006. Restos directos de dinosaurios (Saurischia, Ornithischia) en el Barremiense (Cretacico Inferior) de la Cordillera Iberica en Aragon (Teruel, Espana). Unpublished PhD Thesis. Universidad de Zaragoza. 584 pp.

unnamed paronychodontid (Pol, Buscalioani, Carballeira, Frances, Martinez, Marandat, Moratalla, Sanz, Sige and Villatte, 1992)
Maastrichtian, Late Cretaceous
Calizas de Lychnus Formation, Spain
Material
- four teeth
Comments- These teeth were reported as cf. Paronychodon by Pol et al. (1992), then referred to cf. Euronychodon sp. by Canudo and Ruiz-Omenaca (2003), but they differ from both lacustris and portucalensis in being serrated distally.
References- Pol, Buscalioani, Carballeira, Frances, Martinez, Marandat, Moratalla, Sanz, Sige and Villatte, 1992. Reptiles and mammals from the Late Cretaceous new locality Quintanilla del Coco (Burgos Province, Spain). Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 184(3), 279-314.
Canudo and Ruiz-Omenaca, 2003. Los restos directos de dinosaurios teropódos (excluyendo Aves) en España [Direct remains of theropod dinosaurs (excluding Aves) in Spain]. Ciencias de la Tierra. 26, 347-373.

unnamed paronychodontid (Ruiz-Omeñaca, Canudo, Cuenca-Bescós and Amo, 1998)
Late Hauterivian-Early Barremian, Early Cretaceous
Castellar Formation, Spain
Material
- (MPZ 98-11) tooth (5.32 mm)
Comments- Though this tooth has two ridges on both lingual and labial sides and no mesial serrations, it also has distal serrations (6/mm), so is here excluded from Paronychodon.
References- Ruiz-Omeñaca, Canudo, Cuenca-Bescós and Amo, 1998. Theropod teeth from the Lower Cretaceous of Galve (Teruel, Spain). Third European Workshop on Vertebrate Paleontology, Maastricht. 62-63.
Ruiz-Omenaca, 2006. Restos directos de dinosaurios (Saurischia, Ornithischia) en el Barremiense (Cretacico Inferior) de la Cordillera Iberica en Aragon (Teruel, Espana). Unpublished PhD Thesis. Universidad de Zaragoza. 584 pp.

Paronychodon Cope, 1876
= Euronychodon Antunes and Sigogneau-Russell, 1991
= "Plesiosaurodon" Nessov vide Sues and Averianov, 2013
Diagnosis- serrations absent from teeth.
Comments- This genus is here restricted to paronychodontid teeth without serrations mesially or distally, following Currie et al. (1990). Estes (1964) included serrated specimens with ridges and flattened lingual sides in the genus as well, though these are here referred to Zapsalis abradens (= ?Dromaeosaurus morphotype A of Sankey et al., 2002) and the unnamed troodontid of Sankey et al. (2002). Many unstudied specimens catalogued or listed as Paronychodon probably belong to these two taxa. For instance, one photographed tooth of AMNH 27122 has distal serrations in addition to ridges, so is probably a Zapsalis specimen. Teeth matching the Paronychodon morphotype are known from the Barremian-Maastrichtian of North America and Eurasia, indicating it was probably a clade comparable to theropod families in scope, but which didn't show much dental variation. Once cranial and/or postcranial remains are identified, additional genera of paronychodontids will probably need to be named.
Relationships- Paronychodon was first compared to plesiosaurs by Cope (1876), who soon (1876) realized it was theropod based on comparison to Zapsalis. Most authors retain the genus as Theropoda incertae sedis, though some have tried to clarify its relationships further. Estes (1964) referred it to Coeluridae, while Russell (1984) referred it to Dromaeosauridae, and Osmolska and Barsbold (1990) to Troodontidae. These assignments were all done without justification.
More recently, Zinke and Rauhut (1994) suggested a sister group relationship to troodontids based on the large apically angled distal serrations of the Guimarota paronychodont teeth and the basal constriction in some teeth. These characters are now known in basal dromaeosaurids too (e.g. Microraptor). Rauhut and Zinke (1995) suggested assigning Una Formation Paronychodon teeth to Pelecanimimus, but Rauhut later (2002) considered this unlikely after communication with Perez-Moreno.
Rauhut suggested instead that at least the Una Paronychodon could be archaeopterygids, based on the constricted base, lingually bent carinae (forming mesial and distal grooves along the carinae lingually), and labiodistally twisted tips. Yet the last two characters have yet to be reported from Late Cretaceous Paronychodon, which differs from the Una specimens in several details in any case.
Another hypothesis was given in an abstract by Sankey (2002), who purported to show that Paronychodon is a morphotype of Richardoestesia? isosceles, based on morphology and relative abundance. The details of this study have yet to be published, though it does make sense stratigraphically, as both taxa first appear in Late Jurassic Europe and spread to North America in the Albian, with Late Cretaceous examples known from the Western North America, Central Asia and Europe. It's also logical anatomically, as Richardoestesia? isosceles would be expected to have some unserrated and possibly constricted teeth if it were microraptorian. It should be noted Paronychodon has priority over Richardoestesia, and lacustris and caperatus both have priority over isosceles. Also, Euronychodon has priority over Asiamericana, and portuculensis has priority over both asiatica and asiaticus. So if this synonymy is proven, none of the names associated with straight-toothed Richardoestesia will survive synonymization. Longrich (2008) proposed such a synonymy based on the weak longitudinal ridges on some Richardoestesia teeth, but Larson (2008) noted other contemporaneous theropods sometimes have weak ridges too (tyrannosaurids, 'velociraptorines') and that varied morphologies probably reflect positional variation in Paronychodon teeth. Thus it is unlikely they existed in the same jaws as Richardoestesia teeth.
Sues and Averianov (in prep.) will propose that Paronychodon are juvenile deinonychosaurs, probably in part based on Zapsalis-like specimens which mix paronychodontid longitudinal ridges with dromaeosaurine-like serrations. It is true that Paronychodon teeth are smaller than Dromaeosaurus teeth in the Dinosaur Park Formation, for instance, and that embryonic Troodon has serrationless teeth. Yet apparently intermediate Zapsalis teeth are not intermediate in size, as might be expected if they were subadults. This has not been published besides a mention by Averianov (2007) though, so is difficult to evaluate.
Hwang (2005, 2007) found that Paronychodon teeth are identical in enamel microstructure to serrationless troodontids like Byronosaurus and IGM 100/1323, while Richardoestesia more closely matched dromaeosaurids. Thus they are here placed as basal troodontids
Pachycephalosaur fangs?- An odd possibility was suggested by Olshevsky (DML, 1997), that some Paronychodon specimens, including the holotype, may be anterior dentary fangs of "homalocephalid" pachycephalosaurs (cf. Goyocephale) . However, the dentary fangs of Goyocephale are serrated distally, polygonal in section, have a bulbous root, and seem to only possess one lingual ridge. Premaxillary teeth of Goyocephale are somewhat similar to type B teeth of Paronychodon, but lack ridges, are much less labiolingually compressed, and have distal serrations apically. Stegoceras teeth are even less similar, being serrated both mesially and distally with no ridges. The supposed Middle Jurassic pachycephalosaur Ferganocephale has vertical enamel ridges on the base of one side and lacks serrations, but is otherwise highly distinct, being unrecurved, short and uncompressed labiolingually, with a prominent cingulum. The ridges radiate from the base instead of the apex and the entire tooth shape is distinctively ornithischian. Besides the anatomical differences, stratigraphically Paronychodon and "homalocephalids" are also mismatched, with the latter only known from the Campanian-Maastrichtian of Mongolia and perhaps China. The utter lack of "homalocephalids" in well sampled strata like the Dinosaur Park Formation is particularily telling. Also notable is that each "homalocephalid" only had eight fang-like teeth, but had around sixty-six leaf-shaped teeth. So we would expect more pachycephalosaur teeth by a factor of 8:1 or so (even more in Maastrichtian formations where pachycephalosaurines dominate, with no premaxillary teeth and greater numbers of cheek teeth), but Baszio (1997) showed this is not the case. For instance, he recorded 12 Paronychodon teeth from the Dinosaur Park Formation, and only 16 pachycephalosaur teeth. Similarly, Baszio recorded 84 Paronychodon teeth from the Milk River Formation, but only 16 pachycephalosaur teeth. Finally, Zinke and Rauhut (1994) described paronychodontid teeth within a theropod dentary fragment, though these differ from Paronychodon in some details.
Junior synonyms?- Zapsalis was based on a tooth described by Cope (1876) and synonymized with Paronychodon lacustris by Estes (1964). However, Zapsalis falls outside the current concept of Paronychodon in having serrations, and is more robust than teeth of that genus as well. Instead it matches ?Dromaeosaurus morphotype A of Sankey et al. (2002), and is here used as the valid name for that dromaeosaurid.
Tripriodon was based on teeth assigned to two species by Marsh (1889)- the genotype T. coelatus, and T. caperatus. The former is a junior synonym of the multituberculate Meniscoessus robustus (as first shown by Osborn, 1891), while the second belongs to Paronychodon (as first shown by Estes, 1964). Estes was incorrect in synonymizing Tripriodon itself with Paronychodon however, as T. caperatus is only a referred species. This also prevents Marsh's Tripriodontidae from being a theropod family.
Three teeth were originally referred to Paronychodon lacustris (Antunes and Brion, 1988), but later described as the new genus Euronychodon by Antunes and Sigogneau-Russell (1992). This was based on the supposed absence of longitudinal depressions and a median ridge. Yet longitudinal depressions appear to be present in the figure, while identical ridge patterns are seen in some Paronychodon teeth (e.g. Milk River specimens). Euronychodon is thus retained as a junior synonym of Paronychodon here (as in Sige et al., 1997 and Rauhut, 2002). Numerous other teeth were later referred to Euronychodon from the Barremian-Maastrichtian of Eurasia, but they are here listed as Paronychodon or unnamed paronychodontids.
Variation- Sankey et al. (2002) showed there are two morphotypes of Paronychodon teeth. Type A teeth are elongate and straighter, with unconstricted bases. Type B teeth are short and strongly recurved, with constricted bases. They interpreted these are being due to positional variation instead of taxonomic varation, though it should be noted that the holotypes of both Paronychodon lacustris and Tripriodon caperatus are type A teeth. Thus if taxonomic variation proves correct, these names should only be associated with type A teeth. Based on comparison to other theropods, type B teeth may be more posterior in position.
Baszio (1997) noted that half the teeth are flat lingually, and the other half are biconvex. He considered this due to positional variation, with biconvex teeth being from the posterior portion of the jaw. The FABL, BW and FABL/BW measurements of lingually flat teeth were not significantly different from those of biconvex teeth. Again, the holotypes of both Paronychodon lacustris and Tripriodon caperatus are flattened lingually, which should restrict the names to lingually flat teeth if the variation is later shown to be taxonomic.
References- Cope, 1876. Descriptions of some vertebrate remains from the Fort Union Beds of Montana. Proceedings of the Academy of Natural Sciences of Philadelphia. 28, 248-261.
Cope, 1876. On some extinct reptiles and batrachia from the Judith River and Fox Hills Beds of Montana. Proceedings of the Academy of Natural Sciences, Philadelphia. 28, 340-359.
Marsh, 1889. Discovery of Cretaceous mammalia. American Journal of Science, 3rd series. 38, 81-92.
Osborn, 1891. A review of the "Discovery of the Cretaceous Mammalia". The American Naturalist. 25(295), 595-611.
Estes, 1964. Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming. University of California Publications in Geological Sciences. 49, 1-180.
Russell, 1984. A check list of the families and genera of North American dinosaurs. Syllogeus. 53, 1-35.
Antunes and Brion, 1988. Le Cretace terminal de Beira Litoral, Portugal: remarques stratigraphicques et ecologiques, etude complementaire de Rosasia soutoi (Chelonii, Bothremydidate). Ciencias de Terra. 9, 153-200.
Osmolska and Barsbold, 1990. Troodontidae. In Weishampel, Dodson, and Osmolska, eds.. The Dinosauria, Berkeley: University of California Press: 259-268.
Antunes and Sigogneau-Russell, 1992. La faune de petits dinosaures du Cretace Terminal Portugais. Comun. Serv. Geol. Portugal. 78(1), 49-62.
Zinke and Rauhut, 1994. Small theropods (Dinosauria, Saurischia) from the Upper Jurassic and Lower Cretaceous of the Iberian Peninsula. Berliner geowiss. Abh.. E 13, 163-177.
Rauhut and Zinke, 1995. A description of the Barremian dinosaur fauna from Una with a comparison to that of Las Hoyas. In II International Symposium on Lithographic Limestones, Lleida-Cuenca (Spain), 9th–16th July 1995, Extended Abstracts. 123-126.
Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
http://dml.cmnh.org/1997Dec/msg00058.html
Sige, Buscalioni, Duffaud, Gayet, Orth, Rage and Sanz, 1997. Etat des données sur le gisement Crétacé supérieur continental de Champ-Garimond (Gard, Sud de la France). Munchner Geowiss.. 34, 111-130.
Rauhut, 2002. Dinosaur teeth from the Barremian of Una, Province of Cuenca, Spain. Cretaceous Research. 23, 255-263.
Sankey, 2002. Theropod dinosaur diversity in the latest Cretaceous (Maastrichtian) of North America. Journal of Vertebrate Paleontology. 22(3), 103A.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.
Hwang, 2005. Phylogenetic patterns of enamel microstructure in dinosaur teeth. Journal of Morphology. 266, 208-240.
Averianov, 2007. Theropod dinosaurs from Late Cretaceous deposits in the northeastern Aral Sea region, Kazakhstan. Cretaceous Research.
Hwang, 2007. Phylogenetic patterns of enamel microstructure in dinosaur teeth. PhD thesis. Columbia University. 274 pp.
Larson, 2008. Diversity and variation of theropod dinosaur teeth from the uppermost Santonian Milk River Formation (Upper Cretaceous), Alberta: a quantitative method supporting identification of the oldest dinosaur tooth assemblage in Canada. Canadian Journal of Earth Science. 45, 1455-1468.
Longrich, 2008. Small theropod teeth from the Lance Formation of Wyoming, USA. in Sankey and Baszio (eds). Vertebrate Microfossil Assemblages: Their Role in Paleontology and Paleobiogeography. Indiana University Press, Bloomington, Ind.. pp. 135-158.
Sues and Averianov, 2013. Enigmatic teeth of small theropod dinosaurs from the Upper Cretaceous (Cenomanian–Turonian) of Uzbekistan. Canadian Journal of Earth Sciences. 50, 306-314.
P. lacustris Cope, 1876
Late Campanian, Late Cretaceous
Judith River Formation, Montana, US
Holotype
- (AMNH 3018) type A tooth (10 mm)
Referred - (AMNH 8522) type A tooth (13 mm) (Sahni, 1972)
(AMNH 8523) type B tooth (4.8 mm) (Sahni, 1972)
(AMNH 8524) nine teeth (Sahni, 1972)
(AMNH coll.) seven teeth (Sahni, 1972)
(MOR 017) tooth (MOR online)
Early Campanian, Late Cretaceous
Milk River Formation, Alberta, Canada
Material
- (CMN coll.) teeth (Russell, 1935)
(UA MR-4: 46) tooth (Baszio, 1997)
(UA MR-47) tooth (Baszio, 1997)
(UA MR-48) type B tooth (Baszio, 1997)
(UA MR-49) type A tooth (Baszio, 1997)
(UA MR-50) type A tooth (Baszio, 1997)
(UA MR-51) type A tooth (Baszio, 1997)
(UA MR-52) tooth (Baszio, 1997)
(UA MR-53) type A tooth (Baszio, 1997)
(UA MR-54) type A tooth (Baszio, 1997)
Late Campanian, Late Cretaceous
Dinosaur Park Formation of the Judith River Group, Alberta, Saskatchewan, Canada
Material
- (RTMP 83.36.8) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 84.36.53) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 86.57.62) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 86.60.114) tooth (Ryan and Russell, 2001)
(RTMP 87.19.65) type B tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 87.112.11) type B tooth (4.3 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 88.211.66) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 94.12.187) type A tooth (11.5 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 95.145.53) type B tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 95.177.50) type B tooth (~5.2 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 95.187.28) type B tooth (5.1 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 99.55.61) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 99.55.230) type A tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 2000.19.2) type B tooth (5.2 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
nine teeth (Baszio, 1997)
material (Tokaryk, 1988)
Late Campanian, Late Cretaceous
De-na-zin Member of the Kirtland Formation, New Mexico, US
Material
- (SMP VP-1354) tooth (Sullivan and Lucas, 2006)
Late Maastrichtian, Late Cretaceous
Frenchman Formation, Saskatchewan, Canada
Material
- four teeth (Baszio, 1997)
Diagnosis- (after Sahni, 1972) smaller than P. caperatus and with less defined ridges.
Comments- The holotype has a FABL of 4 mm and a BW of 2.4 mm. It is recurved and flattened lingually with four lingual ridges and six labial ridges. Serrations are absent. It is not from the Hell Creek Formation, contra some sources. Though Sankey et al. (2002) claimed it is not illustrated, Glut (1997) included a photo. Baszio (1997) stated that Paronychodon teeth from the Judith River Group, Milk River Formation and Frenchman Formations were identical. Sullivan and Lucas (2006) in turn stated that SMP VP-1354 from the Kirtland Formation is identical to Milk River teeth. All of these are smaller and with less defined ridges than the Lance Formation species. They can be referred to the species P. lacustris, while the Lance Formation material can be referred to P. caperatus. It's probable other Campanian-Maastrichtian Paronychodon remains (listed as P. sp. below) will be referrable to P. lacustris once they are examined in more detail. Furthermore, this P. lacustris morphotype probably belonged to several different species which differed in non-dental characters, which explains its apparently wide distribution.
References- Cope, 1876. Descriptions of some vertebrate remains from the Fort Union Beds of Montana. Proceedings of the Academy of Natural Sciences of Philadelphia. 28, 248-261.
Russell, 1935. Fauna of the Upper Milk River beds, Southern Alberta. Transactions, Royal Society of Canada. 3(29), 115-127.
Sahni, 1972. The vertebrate fauna of the Judith River Formation, Montana. Bulletin of the AMNH. 147.
Tokaryk, 1988. Preliminary vertebrate faunal list of the Oldman Formation Saskatchewan. Journal of Vertebrate Paleontology. 8(3), 28A.
Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Glut, 1997. Dinosaurs, the Encyclopedia: Mcfarland & Company, Inc., Publishers, 1076pp.
Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.
Sullivan and Lucas, 2006. The Kirtlandian land-vertebrate "age" - faunal composition, temporal position and biostratigraphic correlation in the nonmarine Upper Cretaceous of western North America. New Mexico Museum of Natural History and Science Bulletin. 35, 7-29.
P. caperatus (Marsh, 1889) Olshevsky, 1991
= Tripriodon caperatus Marsh, 1889
= Menisocoessus caperatus (Marsh, 1889)
= Dipriodon caperatus (Marsh, 1889) Currie, Rigby and Sloan, 1990
Late Maastrichtian, Late Cretaceous
Lance Formation, Wyoming, US
Holotype
- (YPM 10624; = YPM 11852) type A tooth
Referred- (AMNH 21550) tooth (AMNH online)
(AMNH 21551) tooth (AMNH online)
(AMNH 21811) twenty-four teeth (AMNH online)
(AMNH 21812) sixteen teeth and fragments (AMNH online)
(AMNH 21813) sixteen teeth (AMNH online)
(AMNH 21814) three teeth (AMNH online)
?(AMNH 21881) two teeth (AMNH online)
?(AMNH 21882) sixteen teeth (AMNH online)
?(AMNH 21883) tooth (AMNH online)
(AMNH 24930) eighteen teeth (AMNH online)
?(AMNH 24931) tooth (AMNH online)
?(AMNH 24932) four teeth (AMNH online)
(AMNH 27122 in part) sixteen teeth and fragments (AMNH online)
?(AMNH coll.) teeth (Estes, 1964)
(SDSM 12459) two teeth (Whitmore, 1988)
(SDSM 12460) tooth (Whitmore, 1988)
(SDSM 12461) tooth (Whitmore, 1988)
(SDSM 12707) tooth (Whitmore, 1988)
(SDSM 15101) tooth fragment (Whitmore, 1988)
(UA BTB: 134) tooth (Baszio, 1997)
(UA BTB: 136) tooth (Baszio, 1997)
(UA BTB: 137) tooth (Baszio, 1997)
(UA BTB: 138) type A tooth (Baszio, 1997)
(UA BTB: 146) tooth (Baszio, 1997)
?(UA BTB: 166) type B tooth (Baszio, 1997)
(UA BTB: coll.) tooth (Baszio, 1997)
(UCM 38288) (juvenile) tooth (4 mm) (Carpenter, 1982)
(UCM 38459) (juvenile) tooth (1.7 mm) (Carpenter, 1982)
(UCMP 53283) tooth (UCMP online)
(UCMP 73075) teeth (UCMP online)
(UCMP 73076) teeth (UCMP online)
(UCMP 85135) tooth (UCMP online)
(UCMP 124400) three teeth (UCMP online)
(UCMP 124401) four teeth (UCMP online)
(UCMP 186863) teeth (UCMP online)
(UCMP 186919) teeth (UCMP online)
(UCMP 187085-187134) fifty teeth (UCMP online)
(UW 14091) tooth (Breithaupt, 1982)
(UW 14092) tooth (Breithaupt, 1982)
?(YPM 10625) tooth (Marsh, 1889)
?(YPM 54481) (YPM online)
?(YPM 54490) (YPM online)
(YPM 54999) (YPM online)
(YPM 55021) (YPM online)
(YPM 55022) (YPM online)
(YPM 55498) (YPM online)
?(YPM 55501) (YPM online)
(YPM 55514) (YPM online)
?(YPM 55517) (YPM online)
?(YPM 55527) (YPM online)
(YPM 55528) (YPM online)
?(YPM 55533) (YPM online)
(YPM 55547) (YPM online)
(YPM 55548) (YPM online)
?(YPM 55585) (YPM online)
(YPM 55594) (YPM online)
(YPM 10630) partial type A tooth (Marsh, 1889)
(YPM coll.) tooth (Osborn, 1891)
tooth (Breithaupt, 2001)
Diagnosis- (after Sahni, 1972) larger than P. lacustris and with better defined ridges.
Comments- Marsh (1889) originally described Tripriodon caperatus based on several teeth and tooth fragments, including supposed lower incisors. The holotype is often listed as YPM 11853, but is 11852 in the YPM online catalog. Although Marsh states the specimen came from Laramie beds, the Laramie Formation has not yielded dinosaurs in Wyoming, and the YPM online catalog confirms it was actually found in the Lance Formation. Marsh viewed T. caperatus and the genotype T. coelatus as belonging to a new family Tripriodontidae in his Allotheria, most closely related to Stereognathus (now recognized as a tritylodontid). Tripriodon coelatus is based on a molar which is now thought to belong to Meniscoessus robustus, a species of multituberculate. This was first recognized by Osborn (1891), who believed T. caperatus were lower incisors of Meniscoessus. Osborn also recognized supposed lower incisors of Selenacodon brevis (YPM 10630) and Tripriodon coelatus (YPM coll.) have the same morphology as T. caperatus. Selenacodon brevis is now viewed as a junior synonym of the multituberculate Cimolemys gracilis. Estes (1964) incorrectly believed T. caperatus to be the genotype, and was the first of many authors to synonymize Tripriodon with Paronychodon. He referred the T. caperatus holotype and YPM 10630 to Paronychodon lacustris. Currie et al. (1990) mistakenly listed Dipriodon caperatus, but Dipriodon is another genus now viewed as a synonym of Meniscoessus.
The holotype tooth seems nearly identical to the Paronychodon holotype except for having a shorter crown. It clearly matches tooth type A of Sankey et al. (2002). Baszio (1997) notes these Lance Formation teeth are larger than Paronychodon lacustris from the Milk River, Dinosaur Park, Frenchman and Horseshoe Canyon Formations, with more pronounced wrinkles. They are retained as Paronychodon caperatus here, after Olshevsky (1991). UA BTB 166 is unique in being biconvex with helical ridges.
References- Marsh, 1889. Discovery of Cretaceous Mammalia. American Journal of Science, 3rd series. 38, 81-92.
Osborn, 1891. A review of the "Discovery of the Cretaceous Mammalia". The American Naturalist. 25(295), 595-611.
Estes, 1964. Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming. University of California Publications in Geological Sciences. 49, 1-180.
Breithaupt. 1982. Paleontology and paleoecology of the Lance Formation, (Maastrichtian), east flank of Rick Springs Uplift, Sweetwater County, Wyoming. Contributions to Geology, University of Wyoming. 21(2), 123-151.
Carpenter, 1982. Baby dinosaurs from the Late Cretaceous Lance and Hell Creek formations and a description of a new species of theropod. Contributions to Geology, University of Wyoming. 20(2), 123-134.
Whitmore, 1988. The vertebrate paleontology of Late Cretaceous (Lancian) localities in the Lance Formation, Northern Niobrara County, Wyoming. Unpublished Masters Thesis. South Dakota School of Mines and Technology, Rapid City, South Dakota. 130pp.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Olshevsky, 1991. A Revison of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodyila. Mesozoic Menanderings #2 (1st printing). iv + 196pp.
Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Breithaupt, 2001. Passport-in-time microvertebrate fossil project at the University of Wyoming Geological Museum: Late Cretaceous Paleontological resources in the public eye. in Santucci and McClelland (eds). Proceedings of the 6th fossil resource conference. United States Department of the interior, National Park Service, Geological Resource Division. 107-112.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.
Stokosa 2005. Enamel microstructure variation within the Theropoda. in Carpenter (ed). The Carnivorous Dinosaurs. 163-178.
P. sp. (Kirkland and Parrish, 1995)
Late Albian, Early Cretaceous
Mussentuchit Member of the Cedar Mountain Formation, Utah, US

Material- (CM 72650) tooth fragment (Fiorillo, 1999)
teeth (Kirkland et al., 1997)
partial type A tooth (Garrison et al., 2007)
Comments- Kirkland and Parrish (1995), Kirkland et al. (1997) and Cifelli et al. (1999) list cf. Paronychodon sp. teeth. Fiorillo (1999) describes a tooth fragment possessing a flattened side with longitudinal ridges which he assigns to "Paronychodon", and believes is a dromaeosaurid tooth based on its cross section. Garrison et al. (2007) describes a partial tooth lacking serrations and a flattened side with three ridges, referring it to cf. Paronychodon sp..
References- Kirkland and Parrish, 1995. Theropod teeth from the Lower Cretaceous of Utah. Journal of Vertebrate Paleontology. 15(3), 39A.
Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
Cifelli, Nydam, Gardner, Weil, Eaton, Kirkland, Madsen, 1999. Medial Cretaceous vertebrates from the Cedar Mountain Formation, Emery County, Utah: the Mussentuchit Local Fauna. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 219-242.
Fiorillo, 1999. Non-mammalian microvertebrate remains from the Robison Eggshell site, Cedar Mountain Formation (Lower Cretaceous), Emery County, Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 259-268.
Garrison, Brinkman, Nichols, Layer, Burge and Thayn, 2007. A multidisciplinary study of the Lower Cretaceous Cedar Mountain Formation, Mussentuchit Wash, Utah: a determination of the paleoenvironment and paleoecology of the Eolambia caroljonesa dinosaur quarry. Cretaceous Research. 28, 461-494.
P? sp. (Krumenacker and Scofield, 2015)
Late Albian-Cenomanian, Early-Late Cretaceous
Wayan Formation, Idaho, US
Material
- (IMNH 2251/49862; Morph 5) tooth (?x~6.2x? mm)
References- Krumenacker and Scofield, 2015. A diverse theropod tooth assemblage from the Mid-Cretaceous (Albian-Cenomanian) Wayan Formation of Idaho. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 158.
Krumenacker, Simon, Scofield and Varricchio, 2016. Theropod dinosaurs from the Albian-Cenomanian Wayan Formation of eastern Idaho. Historical Biology. DOI: 10.1080/08912963.2015.1137913
P. sp. (Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997)
Late Cenomanian, Late Cretaceous
Dakota Formation, Utah, US

Material- teeth
Comments- These were listed as cf. Paronychodon sp. by Kirkland et al. (1997).
Reference- Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
P. sp. (Kirkland, Lucas and Estep, 1998)
Middle-Late Turonian, Late Cretaceous
Smoky Hollow Member of the Straight Cliffs Formation, Utah, US
Material
- (MNA 995) tooth (Parrish, 1999)
(OMNH 24451) tooth (Parrish, 1999)
(OMNH 25415) tooth (Parrish, 1999)
Comments- These were listed as cf. Paronychodon by Kirkland et al. (1998) and Parrish (1999).
References- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
Parrish, 1999. Dinosaur teeth from the Upper Cretaceous (Turonian-. Judithian) of southern Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 319-321.
P. sp. (Kirkland, Lucas and Estep, 1998)
Coniacian-Santonian, Late Cretaceous
John Henry Member of the Straight Cliffs Formation, Utah, US

Comments- This is listed as cf. Paronychodon sp. by Kirkland et al. (1998).
Reference- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
P. sp. (Kirkland, Lucas and Estep, 1998)
Early Campanian, Late Cretaceous
Wahweap Formation, Utah

Comments- This is listed as cf. Paronychodon sp. by Kirkland et al. (1998).
Reference- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
P. sp. (Ryan and Russell, 2001)
Late Campanian, Late Cretaceous
Foremost Formation of the Judith River Group, Alberta, Canada
Material
- (RTMP coll.) teeth
Reference- Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
P. sp. (Ryan and Russell, 2001)
Late Campanian, Late Cretaceous
Oldman Formation of the Judith River Group, Alberta, Canada

Material- (RTMP 92.77.6) tooth
(RTMP coll.) teeth
Reference- Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
P. sp. (Fanti and Miyashita, 2009)
Late Campanian, Late Cretaceous
Wapiti Formation, Alberta, Canada

Material- (UALVP 48815) tooth (3.9x2.3x1.1 mm)
Reference- Fanti and Miyashita, 2009. A high latitude vertebrate fossil assemblage from the Late Cretaceous of west-central Alberta, Canada: Evidence for dinosaur nesting and vertebrate latitudinal gradient. Palaeogeography, Palaeoclimatology, Palaeoecology. 275, 37-53.
P? sp. (Armstrong-Zeigler, 1978)
Late Campanian, Late Cretaceous
Fossil Forest Member of the Fruitland Formation, New Mexico, US

Material- (MNA Pl. 1627) nine teeth (Armstrong-Ziegler, 1978)
(NMMNH P-27490) tooth (?x1.9x1.2 mm) (Williamson and Brusatte, 2014)
(NMMNH P-30276) tooth (1.8x1.3x.5 mm) (Williamson and Brusatte, 2014)
(NMMNH P-30329) tooth (Williamson and Brusatte, 2014)
(NMMNH P-30332) tooth (Williamson and Brusatte, 2014)
(NMMNH P-33479) tooth (~4.3x2x1.1 mm) (Williamson and Brusatte, 2014)
(NMMNH P-38430) tooth (Williamson and Brusatte, 2014)
(NMMNH P-53360) tooth (Williamson and Brusatte, 2014)
Late Campanian, Late Cretaceous
Hunter Wash Member of Kirtland Formation, New Mexico, US

(NMMNH P-29132) tooth (Williamson and Brusatte, 2014)
(NMMNH P-30218) tooth (2.6x1.5x.8 mm) (Williamson and Brusatte, 2014)
(NMMNH P-30233) tooth (?x2.8x1.5 mm) (Williamson and Brusatte, 2014)
(NMMNH P-30234) tooth (?x2.1x1.1 mm) (Williamson and Brusatte, 2014)
Comments- MNA Pl. 1627 were listed as Paronychodon lacustris by Armstrong-Ziegler (1978), but later as Dromaeosauridae incertae sedis by Lucas et al. (1987). Williamson and Brusatte (2014) note this differs from Dinosaur Park Paronychodon in having "less pronounced apicobasal ridges and in lacking ridges that anastomose from the apex to the base of the crown." Some resemble Zapsalis except for lacking distal serrations, so may belong to that taxon.
References- Armstrong-Zeigler, 1978. An aniliid snake and associated vertebrates from the Campanian of New Mexico. Journal of Paleontology. 52(2), 480-483.
Lucas, Mateer, Hunt and O’Neill, 1987. Dinosaurs, the age of the Fruitland and Kirtland Formations, and the Cretaceous-Tertiary boundary in the San Juan Basin, New Mexico. in Fassett and Rigby (eds). The Cretaceous-Tertiary Boundary in the San Juan and Raton Basins, New Mexico and Colorado. The Geological Society of America Special Paper. 209, 35-50.
Williamson and Brusatte, 2014. Small theropod teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and their implications for understanding Latest Cretaceous dinosaur evolution. PLoS ONE. 9(4), e93190.
P. sp. (Kirkland, Lucas and Estep, 1998)
Late Campanian, Late Cretaceous
Kaiparowitz Formation, Utah, US
Material-
(UCM 8304) tooth (Parrish, 1999)
(OMNH 24161) tooth (Parrish, 1999)
(OMNH 24164) tooth (Parrish, 1999)
Comments- These were listed as cf. Paronychodon by Kirkland et al. (1998) and Parrish (1999).
Reference- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
Parrish, 1999. Dinosaur teeth from the Upper Cretaceous (Turonian-. Judithian) of southern Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 319-321.
Late Campanian, Late Cretaceous
Mesaverde Formation, Wyoming, US
Material
- (AMNH 12881) tooth
(AMNH 12882) tooth
(UCMP 120848) tooth (UCMP online)
(UW 34819) tooth
References- Breithaupt, 1985. Nonmammalian vertebrates faunas from the late Cretaceous of Wyoming. Thirty-Sixth Annual Field Conference-1985, Wyoming Geological Association Guidebook. 159-175.
Demar and Breithaupt, 2006. The nonmammalian vertebrate microfossil assemblages of the Mesaverde Formation (Upper Cretaceous, Campanian) of the Wind River and Bighorn Basin, Wyoming. in Lucas and Sullivan (eds). Late Cretaceous Vertebrates from the Western Interior. New Mexico Museum of Natural History & Science, Bulletin. 35, 33-53.
P. sp. (Redman, Moore and Varricchio, 2015)
Late Campanian, Late Cretaceous
Two Medicine Formation, Montana, US
Material
- (MOR 221) tooth (MOR online)
(MOR 505) tooth (MOR online)
(MOR 516) teeth (MOR online)
teeth (Redman, Moore and Varricchio, 2015)
Reference- Redman, Moore and Varricchio, 2015. A new vertebrate microfossil locality in the Upper Two Medicine Formation in the vicinity of Egg Mountain. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 201-202.
P. sp. (Hoganson and Erickson, 2004)
Maastrichtian, Late Cretaceous
Fox Hills Formation, North Dakota, US

Reference- Hoganson and Erickson, 2004. Paleoecological implications of the Fox Hills Formation (Maastrichtian) reptilian and amphibian fauna from south-central North Dakota. Geological Society of America Rocky Mountain and Cordilleran Sections Annual Meeting, Boise, Idaho, Abstracts with Programs. 36(4), 80.
P. sp. (Langston, Standhardt and Stevens, 1989)
Early Maastrichtian, Late Cretaceous
Aguja Formation, Texas, US
Material
- (LSU 113:1310) type A tooth (~5.5 mm)
(LSU 113:1311) type A tooth
(LSU 113:5107) type A tooth (~3 mm)
(LSU 113:5993) type A tooth (~2.5 mm)
(LSU 113:5996) type A tooth
References- Langston, Standhardt and Stevens, 1989. Fossil vertebrate collecting in the Big Bend - History and retrospective. in Vertebrate Paleontology, Biostratigraphy and Depositional Environments, Latest Cretaceous and Tertiary, Big Bend Area, Texas. Guidebook Field Trip Numbers 1 a, B, and 49th Annual Meeting of the Society of Vertebrate Paleontology, Austin, Texas, 29 October - 1 November 1989. 11-21.
Sankey, Standhardt and Schiebout, 2005. Theropod teeth from the Upper Cretaceous (Campanian-Maastrichtian), Big Bend National Park, Texas. in Carpenter (ed). The Carnivorous Dinosaurs. 127-152.
P. sp. (Baszio, 1997)
Early Maastrichtian, Late Cretaceous
Horseshoe Canyon Formation, Alberta, Canada
Material
- (RTMP 97.39.6) partial type A tooth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP 1041) tooth (Baszio, 1997)
(RTMP 2009.139.4) tooth (Larson, Brinkman and Bell, 2010)
Comments- RTMP 97.39.6 is flat lingually and convex labially. It has eight lingual ridges and ten labial ones. RTMP 2009.139.4 also has that convexity, but also faint serrations.
References- Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Ryan, Currie, Gardner and Livigne, 1997. Baby hadrosaurid material associated with an unusually high abundance of troodontid teeth from the Horseshoe Canyon Formation (Early Maastrichtian), Alberta, Canada. Journal of Vertebrate Paleontology. 17(3), 72A.
Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998. Baby hadrosaurid material associated with an unusually high abundance of Troodon teeth from the Horseshoe Canyon Formation, Upper Cretaceous, Alberta, Canada. Gaia. 15, 123-133.
Larson, Brinkman and Bell, 2010. Faunal assemblages from the upper Horseshoe Canyon Formation, an early Maastrichtian cool-climate assemblage from Alberta, with special reference to the Albertosaurus sarcophagus bonebed. Canadian Journal of Earth Sciences. 47(9), 1159-1181.
P. sp. (Estes, Berberian and Mesozoely, 1969)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, South Dakota, US
Material-
(AMNH 21555) tooth (AMNH online)
(MCZ 3645) two teeth (Estes, Berberian and Mesozoely, 1969)
(UCMP 119922) tooth (UCMP online)
(UCMP 119923) tooth (UCMP online)
(UCMP 120076) tooth (UCMP online)
(UCMP 120192) tooth (UCMP online)
(UCMP 120254) tooth fragment (UCMP online)
(UCMP 123341) tooth (UCMP online)
(UCMP 124405) tooth (UCMP online)
(UCMP 124990) (juvenile) type B tooth (3.4 mm) (Carpenter, 1982)
(UCMP 124991) (juvenile) tooth (4.8 mm) (Carpenter, 1982)
(UCMP 124992) (juvenile) tooth (4.3 mm) (Carpenter, 1982)
(UCMP 128764) three teeth (UCMP online)
(UCMP 186867) teeth (UCMP online)
(UCMP 186876) teeth (UCMP online)
(UCMP 186879) teeth (UCMP online)
(UCMP 186884) teeth (UCMP online)
(UCMP 186898) teeth (UCMP online)
(UCMP 186910) teeth (UCMP online)
(UCMP 186923) teeth (UCMP online)
(UCMP 187080) tooth (UCMP online)
(UCMP 187081) tooth (UCMP online)
(UCMP 187082) tooth (UCMP online)
(UCMP 187135-187156) twenty-two teeth (UCMP online)
(YPM PU 20571) (Estes, Berberian and Mesozoely, 1969)
teeth (Stenerson and O'Conner, 1994)
teeth (Triebold, 1997)
teeth (DePalma, 2010)
References- Estes, Berberian and Mesozoely, 1969. Lower vertebrates from the Late Cretaceous Hell Creek Formation, McCone County, Montana. Breviora. 337, 1-33.
Carpenter, 1982. Baby dinosaurs from the Late Cretaceous Lance and Hell Creek formations and a description of a new species of theropod. Contributions to Geology, University of Wyoming. 20(2), 123-134.
Stenerson and O'Conner, 1994. The Late Cretaceous Hell Creek Formation of Northwestern South Dakota and its Fauna. MAPS Digest. 17(4), 108-120.
Triebold, 1997. The Sandy Site: Small Dinosaurs from the Hell Creek Formation of South Dakota. in Wolberg, Stump and Rosenberg (eds). Dinofest International, Proceedings of a Symposium sponsered by Arizona State University. A Publication of The Academy of Natural Sciences. 245-248.
DePalma, 2010. Geology, taphonomy, and paleoecology of a unique Upper Cretaceous bonebed near the Cretaceous-Tertiary boundary in South Dakota. Masters thesis, University of Kansas. 227 pp.
P. sp. (Wroblewski, 1995)
Late Maastrichtian, Late Cretaceous
Ferris Formation, Wyoming, US
Material
- teeth
References- Wroblewski, 1995. First report of changes in Lower Vertebrate Faunas across the Cretaceous-Tertiary boundary, Western Hanna Basin, Wyoming. Journal of Vertebrate Paleontology. 15(3), 61A.
Wroblewski, 1998. Changing paleoenvironments and paleofaunas across the K-T boundary, Ferris Formation, Southcentral Wyoming. Tate Geological Museum, Casper College, Casper Wyoming. Tate ’98. Life in the Cretaceous. 53-70.
P. sp. indet.
Cretaceous
Montana, US
Material
- (AMNH 2134) tooth (AMNH online)
?Cretaceous
US
Material
- (YPM 56974) (YPM online)
P. sp. nov. (Rauhut and Zinke, 1995)
Late Barremian, Early Cretaceous
Una (= Calizas de La Huergina) Formation, Spain
Material
- (IPFUB Una Th 53, 55-61, 69) thirteen teeth (to 6 mm) (Rauhut and Zinke, 1995)
(IPFUB Una Th 69) tooth (Rauhut, 2002)
Comments- These teeth are slightly recurved, with no mesial or distal serrations. They have a flattened lingual side with a central ridge, while some specimens also have a weak labial ridge. Some teeth have a slight basal constriction. Rauhut and Zinke (1995) originally referred these specimens to cf. Euronychodon sp., though they were later referred to cf. Paronychodon sp. by Rauhut (2002).
References- Rauhut and Zinke, 1995. A description of the Barremian dinosaur fauna from Una with a comparison to that of Las Hoyas. In II International Symposium on Lithographic Limestones, Lleida-Cuenca (Spain), 9th–16th July 1995, Extended Abstracts. 123-126.
Rauhut, 2002. Microrestos de dinosaurios del Cretácico inferior de Uña, España. Resumenes de las XVIII Jornadas Argentinas de Paleontología de Vertebrados. Bahia Blanca, Argentina. 36.
Rauhut, 2002. Dinosaur teeth from the Barremian of Una, Province of Cuenca, Spain. Cretaceous Research. 23, 255-263.
P? sp. (Averianov, Leshchinskiy, Skutschas, Fayngertz and Rezvyi, 2004)
Aptian-Albian, Early Cretaceous
Ilek (=Shestakovo) Formation, Russia
Material
- teeth
Comments- Referred to cf. Paronychodon.
Reference- Averianov, Leshchinskiy, Skutschas, Fayngertz and Rezvyi, 2004. Dinosaurs from the Early Cretaceous Ilek Formations in West Siberia, Russia. 2nd EAVP Meeting. July 19-24, 2004. Brno, Czech Republic. Abstracts of papers and posters with program, Excursion Guidebook. pg 6.
P. asiaticus (Nessov, 1995) Sues and Averianov, 2013
= Euronychodon asiaticus Nessov, 1995
= "Plesiosaurodon" sp. Nessov vide Sues and Averianov, 2013
Mid-Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan

Holotype- (CCMGE N 9/12454) type A tooth
Paratypes- (CCMGE coll.) six teeth
Referred- (ZIN PH 301/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1052/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1053/16) type A tooth (Sues and Averianov, 2013)
(ZIN PH 1054/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1055/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1056/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1057/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1058/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1059/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1060/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1061/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1062/16) premaxillary tooth (Sues and Averianov, 2013)
(ZIN PH 1063/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1064/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1065/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1066/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1067/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1068/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1069/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1070/16) premaxillary tooth (Sues and Averianov, 2013)
(ZIN PH 1072/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1147/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1149/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1150/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1151/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1152/16) type A tooth (Sues and Averianov, 2013)
(ZIN PH 1345/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1833/16) type A tooth (Sues and Averianov, 2013)
Middle Albian-Early Cenomanian, Early-Late Cretaceous
Khodzhakul Formation, Uzbekistan

(ZIN PH 1071/16) type B tooth (Sues and Averianov, 2013)
(ZIN PH 1220/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1221/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1228/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1229/16) tooth (Sues and Averianov, 2013)
(ZIN PH 1230/16) tooth (Sues and Averianov, 2013)
Diagnosis- (after Sues and Averianov, 2013) can differ from P. lacustris in having a higher number of labial ridges (up to 17 versus up to 14).
Comments- These teeth were first described as?Plesiosauria (Nessov, 1985) and Paronychodon cf. lacustris (Nessov, 1986) before being described as a new species of Euronychodon by Nessov (1995). Nessov (1995) distinguished it from Euronychodon portucalensis based on the presence of numerous labial grooves, but the latter are seen in a paratype of E. portucalensis. Sues and Averianov (2013) redescribed the teeth as Paronychodon asiaticus, and noted some specimens were labelled "Plesiosaurodon" by Nessov. Averianov (2007) first announced Paronychodon sp. from the Khodzhakul Formation, which were also described by Sues and Averianov and referred to P. asiaticus.
References- Nessov, 1985. [New mammals of the Cretaceous of the Kyzylkum]. Vyestnik Lyeningradskogo univyersityeta, Biologiya. 17, 8-18.
Nessov, 1986. [The first discovery of the Late Cretaceous bird Ichthyornis in the Old World and some other bones of birds from the Cretaceous and Paleogene of Middle Asia]. Trudy Zoologichyeskogo Instituta AN SSSR. 147, 31-38.
Nessov, 1995. Dinozavri severnoi Yevrazii: Novye dannye o sostave kompleksov, ekologii i paleobiogeografii. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg. 156 pp.
Averianov, 2007. Theropod dinosaurs from Late Cretaceous deposits in the northeastern Aral Sea region, Kazakhstan. Cretaceous Research. 28(3), 532-544.
Sues and Averianov, 2013. Enigmatic teeth of small theropod dinosaurs from the Upper Cretaceous (Cenomanian-Turonian) of Uzbekistan. Canadian Journal of Earth Sciences. 50, 306-314.
P. sp. (Garcia, Duffaud, Feist, Marandat, Tambareau, Villatte and Sige, 2000)
Turonian-Maastrichtian, Late Cretaceous
La Nueve, Aix, France
Material
- (LNE-D01) tooth
Reference- Garcia, Duffaud, Feist, Marandat, Tambareau, Villatte and Sige, 2000. La neuve, gisement a plantes, invertebres et vertebres du Begudien (Senonien superieur continental) du bassin d’Aix-en-Provence. Geodiversitas. 22(3), 326-348.
P? sp. (Sige, Buscalioni, Duffaud, Gayet, Orth, Rage and Sanz, 1997)
Campanian, Late Cretaceous
unnamed unit, Champ-Garimond, Gard, France
Material
- teeth
Comments- These differ from most Paronychodon specimens in lacking carinae. They were assigned to Paronychodon by Sige et al. (1997).
Reference- Sige, Buscalioni, Duffaud, Gayet, Orth, Rage and Sanz, 1997. Etat des données sur le gisement Crétacé supérieur continental de Champ-Garimond (Gard, Sud de la France). Munchner Geowiss.. 34, 111-130.
P? sp. (Le Loeuff, 1992)
Late Campanian, Late Cretaceous
Vitoria Formation, Spain
Material
- teeth
Comments- These were listed as cf. Euronychodon sp. by Suberbiola et al. (2000).
References- Le Loeuff, 1992. Les vertébrés continentaux du Crétacé supérieur d'Europe: Paléoécologie, Biostratigraphie et Paléobiogéographie. Mémoires des Sciences de la Terre de l'Université Pierre et Marie Curie, Paris, (Thèse d'Université, non publié). 92-3, 273 pp.
Astibia, Murelaga, Pereda-Suberbiola, Elorza and Gomez-Alday, 1999. Taphonomy and palaeoecology of the Upper Cretaceous continental vertebrate-bearing beds of the Laño Quarry (Iberian Peninsula). Est. Mus. Cienc. Nat. de Alava. 14 (Núm. Espec. 1), 43-104.
Pereda-Suberbiola, Asibia, Murelaga, Elzorza and Gomez-Alday, 2000. Taphonomy of the Late Cretaceous dinosaur-bearing beds of the Lano Quarry (Iberian Peninsula). Palaeogeography, Palaeoclimatology, Palaeoecology. 157, 247-275.
P? sp. (Torices, Barroso-Barcenilla, Cambra-Moo, Perez and Serrano, 2011)
Late Campanian-Early Maastrichtian, Late Cretaceous
Villalba de la Sierra Formation, Spain
Material
- teeth
Comments- Torices et al. (2011) mention cf. Paronychodon.
Reference- Torices, Barroso-Barcenilla, Cambra-Moo, Perez and Serrano, 2011. Vertebrate microfossil analysis in the palaeontological site of 'Lo Hueco' (Upper Cretaceous, Cuenca, Spain). Journal of Vertebrate Paleontology. Program and Abstracts 2011, 205.
P. portucalensis (Antunes and Sigogneau-Russell, 1991) new comb.
= Euronychodon portucalensis Antunes and Sigogneau-Russell, 1991
Late Campanian-Early Maastrichtian, Late Cretaceous
unnamed unit, Taviero, Portugal

Holotype- (CEPUNL TV 20) type A tooth (1.8 mm)
Paratypes- (CEPUNL TV 18) type B tooth
(CEPUNL TV 19) tooth
Diagnosis- provisionally indeterminate within Paronychodon.
Comments- These teeth were originally referred to Paronychodon lacustris (Antunes and Brion, 1988). They were later described as the new genus Euronychodon by Antunes and Sigogneau-Russell (1992) based on the supposed absence of longitudinal depressions and a median ridge. Yet longitudinal depressions appear to be present in the figure, while identical ridge patterns are seen in some Paronychodon teeth (e.g. Milk River specimens). Euronychodon is thus retained as a junior synonym of Paronychodon here (as in Rauhut, 2002).
References- Antunes and Brion, 1988. Le Cretace terminal de Beira Litoral, Portugal: remarques stratigraphicques et ecologiques, etude complementaire de Rosasia soutoi (Chelonii, Bothremydidate). Ciencias de Terra. 9, 153-200.
Antunes and Sigogneau-Russell, 1992. La faune de petits dinosaures du Cretace Terminal Portugais. Comun. Serv. Geol. Portugal. 78(1), 49-62.
Rauhut, 2002. Dinosaur teeth from the Barremian of Una, Province of Cuenca, Spain. Cretaceous Research. 23, 255-263.
P. sp. (Lopez-Martinez, Canudo, Ardevol, Pereda-Suberbiola, Orue-Etxebarria, Cuenca-Bescos, Ruiz-Omenaca, Muerlaga and Feist, 2001)
Late Maastrichtian, Late Cretaceous
Tremp (=Arenisca) Formation, Spain
Material
- (MPZ98/76) tooth (2.7x1.5x.6 mm)
(MPZ98/77) tooth (2.8x1.4x.6 mm)
(MPZ98/78) tooth (2.2x1.2x.8 mm)
Comments- These are strongly recurved and have three labial ridges. They were described as unserrated. While MPZ 98-76 is listed as having 15.97 distal serrations per mm by Lopez-Martinez et al. (2001), Torices et al. (2015) list it as serrationless and provide a figure demonstrating this is so. They were listed as cf. Euronychodon sp. by Lopez-Martinez et al., and cf. Paronychodon sp. by Torices et al..
References- Canudo, Lopez Martinez and Ruiz Omenaca, 2001. Los dinosaurios del Maastrichtiense Superior (Cretacico Superior) del pirineo de Huesca (Espana). Actas de Las I Jornadas Internacionales sobre Paleontologia de Dinosaurios y su entorno. 319-328.
Lopez-Martinez, Canudo, Ardevol, Pereda-Suberbiola, Orue-Etxebarria, Cuenca-Bescos, Ruiz-Omenaca, Muerlaga and Feist, 2001. New dinosaur sites correlated with Upper Maastrichtian pelagic deposits in the Spanish Pyrenees: Implications for the dinosaur extinction pattern in Europe. Cretaceous Research. 22, 41-61.
Torices, Currie, Canudo and Pereda-Suberbiola, 2015. Theropod dinosaurs from the Upper Cretaceous of the South Pyrenees Basin of Spain. Acta Palaeontologica Polonica. 60(3), 611-626.
P. sp. nov. (Csiki and Grigorescu, 1998)
Late Maastrichtian, Late Cretaceous
Sinpetru Beds, Romania
Material
- (FGGUB R.1431) type A tooth (5.1 mm) (Csiki and Grigorescu, 1998)
type A tooth (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
teeth (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
Comments- FGGUB R.1431 differs from most Paronychodon specimens in having only two lingual grooves and lacking labial grooves. A tooth morphotype illustrated by Codrea et al. (2002) is elongate and strongly recurved, lacks serrations, is not as asymmetrical as Paronychodon, and is said to lack ridges or grooves. Csiki and Grigorescu refer FGGUB R.1431 to cf. Euronychodon, while Codrea et al. refer to their teeth as Euronychodon morphotype.
References- Csiki and Grigorescu, 1998. Small theropods from the Late Cretaceous of the Hateg Basin (Western Romania) - an unexpected diversity at the top of the food chain. Oryctos. 1, 87-104.
Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002. Dinosaur egg nests, mammals and other vertebrates from a new Maastrichtian site of the Hateg Basin (Romania). C. R. Palevol. V. 1, p. 173-180.
P. sp. (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
Late Maastrichtian, Late Cretaceous
Sinpetru Beds, Romania

Material- partial type A tooth (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
teeth (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
Comments- This tooth type is referred to the Paronychodon morphotype by Codrea et al.(2002). It lacks serrations, is flat on one side, and has several longitudinal ridges.
Reference- Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002. Dinosaur egg nests, mammals and other vertebrates from a new Maastrichtian site of the Hateg Basin (Romania). C. R. Palevol. V. 1, p. 173-180.

Yaverlandia Galton, 1971
Y. bitholus Galton, 1971
Barremian, Early Cretaceous
Wessex Formation, England

Holotype- (MIWG 1530) frontals, postorbital fragment, orbitosphenoid fragment
Diagnosis- frontals domed; frontals with pitted surface.
Comments- This specimen was originally considered to perhaps be referrable to Vectisaurus (Watson, 1930; Swinton, 1936), though Watson also noted resemblence to pachycephalosaurids. Galton (1971) named the taxon Yaverlandia bitholus, and assigned it to the Pachycephalosauridae, which was followed by most authors until recently. When entered into cladistic analyses of Pachycephalosauria, Yaverlandia was resolved at the base of the clade (Williamson and Carr, 2002) or as a basal pachycephalosaurid (Sereno, 2000). However, Hopson (1979) and Giffin (1989) doubted a pachycephalosaurian identity, based on the structure of the endocranium. Sullivan (2000, 2003) noted several characters incongruent with a pachycephalosaurian identity- frontals with broad orbital contact; parietals excluded from domes; supratemporal fenestrae contact frontals. Naish (2004) determined Yaverlandia is not a pachycephalosaur, though its identity remained elusive in his abstract. Naish (2006) classified the genus as a maniraptoran in his unpublished thesis, based on ventrally extending, laterally concave ridges that form the lateral margins of the cerebral concavity, ventrally concave dorsal orbital margins, a distinctly bilobed cerebral concavity, and small, narrow olfactory bulbs. This was reported in the publications of Sullivan (2006) and Naish (2011). Naish (2011) further indicates it's probably a troodontid and will be described in more detail in the future.
References- Watson, 1930. Proceedings of the Isle of Wight Natural History Society. 2, 60.
Swinton, 1936. The dinosaurs of the Isle of Wight. Proceedings of the Geologists' Association. 47, 204-220.
Galton, 1971. A primitive dome-headed dinosaur (Ornithischia; Pachycephalosauridae) from the Lower Cretaceous of England and the function of the dome of pachycephalosaurids. Journal of Paleontology. 45(1), 40-47.
Hopson, 1979. Paleoneurology. In Gans, Northcutt and Ulinski (eds.). Biology of the Reptilia (Neurology A). Academic Press, New York. 9, 39-146.
Giffin, 1989. Pachycephalosaur paleoneurology (Archosauria: Ornithischia). Journal of Vertebrate Paleontology. 9(1), 67-77.
Sereno, 2000. The fossil record, systematics and evolution of pachycephalosaurs and ceratopsians from Asia. In Benton, Shishkin, Unwin and Kurochkin (eds.). The Age of Dinosaurs in Russia and Mongolia. Cambridge University Press, New York. 480-516.
Sullivan, 2000. Prenocephale edmontonensis (Brown and Schlaikjer) new comb. and P. brevis (Lambe) new comb. (Dinosauria: Ornithischia: Pachycephalosauria) from the Upper Cretaceous of North America. New Mexico Museum of Natural History and Science Bulletin. 17, 177-190.
Naish and Martill, 2001. Boneheaded and horned dinosaurs. In Martill and Naish (eds.). Dinosaurs of the Isle of Wight. The Palaeontological Association, London. 133-146.
Williamson and Carr, 2002. A new genus of derived pachycephalosaurian from Western North America. Journal of Vertebrate Paleontology. 22(4), 779-801.
Sullivan, 2003. Revision of the dinosaur Stegoceras Lambe (Ornithischia, Pachycephalosauridae). Journal of Vertebrate Paleontology. 23(1), 181-207.
Naish, 2004. So... what is Yaverlandia? SVPCA 2004 Abstracts.
Naish, 2006. The osteology and affinities of Eotyrannus lengi and Lower Cretaceous theropod dinosaurs from England. PhD thesis, University of Portsmouth.
Sullivan, 2006. A taxonomic review of the Pachycephalosauridae (Dinosauria: Ornithischia). New Mexico Museum of Natural History and Science Bulletin. 35, 347-365.
Naish, 2011. Theropod dinosaurs. In Batten (ed.). English Wealden Fossils. The Palaeontological Association. 526-559.

undescribed Troodontidae (Bolotsky and Moiseenko, 1988)
Late Maastrichtian, Late Cretaceous
Udurchukan Formation of the Tsagayan Group, Russia
Material
- teeth
Comments- These teeth have been noted as Troodontidae indet. (Bolotsky and Moiseenko, 1988; Nessov and Golovneva, 1990; Nessov, 1995), Troodon cf. formosus (Moiseenko et al., 1997) and Troodon sp. (Alifanov and Bolotsky, 2002), but have yet to be described.
References- Bolotsky and Moiseenko, 1988. [On Dinosaurs of the Amur River Region.] Amur KNII DVO AN SSSR, Blagoveshchensk, 38pp. [Russian]
Nessov and Golovneva, 1990. [History of the flora, vertebrates and climate in the late Senonian of the north-eastern Koriak Uplands]; pp. 191–212 in V. A. Krasilov (ed.), [Continental Cretaceous of the USSR.] Dal’nevostochnoe Otdelenie AN SSSR, Vladivostok. [Russian]
Nessov, 1995. Dinosaurs of nothern Eurasia: new data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg 1-156.
Moiseenko, Sorokin and Bolotsky, 1997. [Fossil Reptiles of the Amur River Area.] Amurskii Nauchnyi Tsentr DVO RAN, Khabarovsk, 54 pp. [Russian]
Alifanov and Bolotsky, 2002. New data about the assemblages of the Upper Cretaceous carnivorous dinosaurs (Theropoda) from the Amur region. In Kirillova (ed.). Fourth International Symposium of IGCP 434. Cretaceous continental margin of East Asia: Stratigraphy, sedimentation, and tectonics. 25-26.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.

undescribed possible troodontid (Brett-Surman, Jabo, Kroehler, Carrano and Kvale, 2005)
Kimmeridgian-Early Tithonian, Late Jurassic
Morrison Formation, Wyoming, US
Material
- tooth
Comments- Brett-Surman et al. (2005) state this tooth has troodontid-like serrations. It may belong to Koparion or the taxon represented by WDC DML0001.
Reference- Brett-Surman, Jabo, Kroehler, Carrano and Kvale, 2005. A new microvertebrate assemblage from the Upper Jurassic Morrison Formation, including mammals, theropods, and sphenodontians. Journal of Vertebrate Paleontology. 25(3), 39A.

undescribed possible Troodontidae (Chure, 1995)
Late Kimmeridgian, Late Jurassic
Brushy Basin Member of the Morrison Formation, Utah, US
Material
- teeth
Reference- Chure, 1995. The teeth of small theropods from the Morrison Formation (Upper Jurassic: Kimmeridgian), UT. Journal of Vertebrate Paleontology. 15(3), 23A.

undescribed Troodontidae (Cifelli, Gardner, Nydam and Brinkman, 1997)
Early-Middle Albian, Early Cretaceous
Antlers Formation, Oklahoma, US

Reference- Cifelli, Gardner, Nydam and Brinkman, 1997. Additions to the vertebrate fauna of the Antlers Formation (Lower Cretaceous), southeastern Oklahoma. Oklahoma Geology Notes. 57(4), 124-131.

undescribed possible Troodontidae (Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997)
Late Albian, Early Cretaceous
Mussentuchit Member of the Cedar Mountain Formation, Utah, US

Material- teeth
Comments- These are identified as cf. Troodon sp. in Kirkland et al. (1997), and Troodontidae gen. et sp. indet. by Cifelli et al. (1999). They are probably the troodontid teeth mentioned by Parrish and Eaton (1991) and Kirkland and Parrish (1995) from the Cedar Mountain Formation.
References- Parrish and Eaton, 1991. Diversity and Evolution of Dinosaurs in the Cretaceous of the Kaipirowits Plateau, Utah. Journal of Vertebrate Paleontology. 11(3), 50A.
Kirkland and Parrish, 1995. Theropod teeth from the Lower Cretaceous of Utah. Journal of Vertebrate Paleontology. 15(3), 39A.
Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
Cifelli, Nydam, Gardner, Weil, Eaton, Kirkland, Madsen, 1999. Medial Cretaceous vertebrates from the Cedar Mountain Formation, Emery County, Utah: the Mussentuchit Local Fauna. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 219-242.

undescribed Troodontidae (Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997)
Late Cenomanian, Late Cretaceous
Dakota Formation, Utah, US
Material
- teeth
Comments- These are identified as cf. Troodon sp. in Kirkland et al. (1997) and later references.
Reference- Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
Eaton, Cifelli, Hutchison, Kirkland and Parrish, 1999. Cretaceous vertebrate faunas from the Kaiparowits Plateau, south central Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 345-353.

undescribed troodontid (Eaton, 1999)
Late Cenomanian-Early Turonian?, Early-Late Cretaceous
Iron Springs Formation, Utah, US

Material- teeth
Reference- Eaton, 1999. Vertebrate paleontology of the Iron Springs Formation, Upper Cretaceous, southwestern Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 339-343.

undescribed Troodontidae (Kirkland, Lucas and Estep, 1998)
Middle-Late Turonian, Late Cretaceous
Smoky Hollow Member of the Straight Cliffs Formation, Utah, US
Material
- teeth
Reference- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.

undescribed Troodontidae (Kirkland, Lucas and Estep 1998)
Coniacian-Santonian, Late Cretaceous
John Henry Member of the Straight Cliffs Formation, Utah, US

Reference- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.

undescribed Troodontidae (Kirkland, Lucas and Estep 1998)
Early Campanian, Late Cretaceous
Wahweap Formation, Utah, US
Material
- (OMNH 21988) tooth (Parrish, 1999)
(OMNH 24237) tooth (Parrish, 1999)
Comments- Parrish (1999) referred two teeth to cf. Troodon. Eaton et al. listed them as Troodon sp..
References- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
Eaton, Cifelli, Hutchison, Kirkland and Parrish, 1999. Cretaceous vertebrate faunas from the Kaiparowits Plateau, south central Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 345-353.
Parrish, 1999. Dinosaur teeth from the Upper Cretaceous (Turonian-. Judithian) of southern Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 319-321.

undescribed Troodontidae (Parrish and Eaton, 1991)
Late Campanian, Late Cretaceous
Kaiparowitz Formation, Utah, US
Material
- (ALF coll.) teeth (Zanno et al., 2011)
(OMNH 21958) tooth (Parrish, 1999)
(UCM 83253) tooth (Parrish, 1999)
(UCM 8659; in part) tooth (Parrish, 1999)
(UCMP 149171) partial squamosals, parietals, basioccipital, proximal tibia, fragmentary metatarsals, pedal phalanges, pedal unguals (Zanno et al., 2009; described by Zanno et al., 2011)
(UMNH VP 11806) dentary tooth (Zanno et al., 2011)
(UMNH VP 12507) maxillary tooth (Zanno et al., 2011)
(UMNH VP 16303) frontal (Zanno, 2007; described by Zanno et al., 2011)
(UMNH VP coll.) distal caudal vertebra (Zanno et al., 2009; described by Zanno et al., 2011)
(UMNH VP coll.) teeth (Zanno et al., 2011)
Comments- The partial skeleton was discovered in 1994. Zanno et al. (2009) mistakenly cite it as UCMP 143270, which is a Parasaurolophus specimen. Zanno et al. (2011) briefly describe the remains and note they may be referrable to the contemporaneous Talos. Zanno (2007) first mentioned UMNH VP 16303 as a taxon distinct from Troodon, though it was later relegated to Troodontidae indet..
References- Parrish and Eaton, 1991. Diversity and Evolution of Dinosaurs in the Cretaceous of the Kaipirowits Plateau, Utah. Journal of Vertebrate Paleontology. 11(3), 50A.
Parrish, 1999. Dinosaur teeth from the Upper Cretaceous (Turonian-. Judithian) of southern Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 319-321.
Zanno, 2007. A new troodontid theropod from the Late Campanian Kaiparowits Formation, southern Utah. Journal of Vertebrate Paleontology. 27(3), 170A-171A.
Zanno, Varricchio, Titus, Wilkins and Knell, 2009. A new troodontid (Theropoda: Paraves) specimen from the Upper Campanian Kaiparowitz Formation, Southern Utah: Estimating the taxonomic diversity of North American Troodontidae. Journal of Vertebrate Paleontology. 29(3), 205A.
Zanno, Varricchio, O’Connor, Titus and Knell, 2011. A new troodontid theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous western interior basin of North America. PLoS ONE. 6(9), e24487.

undescribed troodontid (Lehman, 1981)
Late Campanian, Late Cretaceous
Lower Kirkland Formation, New Mexico, US
Material
- (UNM FKK-014) teeth
Reference- Lehman, 1981. The Alamo Wash Local Fauna: a new look at the old Ojo Alamo Fauna. in Lucas, Rigby and Kues (eds.). Advances in San Juan Basin Paleontology. New Mexico University Press, Albuquerque, New Mexico. 189-221.

undescribed Troodontidae (Kirkland, Lucas and Estep, 1998)
Late Maastrichtian, Late Cretaceous
North Horn Formation, Utah, US

Material- (OMNH and/or UMNH coll.) teeth
nest, 13 eggs (~170x~76 mm) (Difley, Britt and Policelli, 2004)
Comments- Kirkland et al. (1998) and Cifelli et al. (1999) mention Troodontidae gen. et sp. indet. from the North Horn Formation. Difley et al. 92004) report a nest of Prismatoolithus eggs referrable to Troodontidae.
References- Kirkland, Lucas and Estep, 1998. Cretaceous dinosaurs of the Colorado Plateau. in Lucas, Kirkland and Estep (eds.). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin. 14, 79-89.
Cifelli, Nydam, Eaton, Gardner, Kirkland, 1999. Vertebrate faunas of the North Horn Formation (Upper Cretaceous-lower Paleocene), Emery and Sanpete counties, Utah. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 378-388.
Difley, Britt and Policelli, 2004. A troodontid nest in the North Horn Formation, central Utah. Journal of Vertebrate Paleontology. 24(3), 115A.

unnamed possible troodontid (Huene, 1934)
Santonian-Campanian, Late Cretaceous
Pallacio (Guichon) Formation, Uruguay
Material
- tooth
Comments- This was listed on www.paleofile.com as a troodontid. It is preseumably tooth B of Huene (1934), identified by him as an ornithomimid.
Reference- Huene. 1934. Neue Saurier-Zähne aus der Kreide von Uruguay [New saurian teeth from the Cretaceous of Uruguay]. Centralblatt für Mineralogie, Geologie und Paläontologie, Abteilung B: Geologie und Paläontologie. 1934(4),183-189.

undescribed Troodontidae (Bertini and Franco-Rosas, 2001)
Turonian-Late Maastrichtian, Late Cretaceous
Adamantina and Marilia Formations, Bauru Group, Brazil

Material- teeth
Reference- Bertini and Franco-Rosas, 2001. Scanning electron microscope analysis on Maniraptoriformes teeth from the Upper Cretaceous of Southeastern Brazil. JVP 21(3) 33A.

unnamed Troodontidae (Estes and Sanchiz, 1982)
Late Hauterivian-Early Barremian, Early Cretaceous
Castellar Formation, Spain
Material
- teeth
Comments- These were referred to Coelosauridae by Estes and Sanchiz (1982).
Reference- Estes and Sanchiz, 1982. Early Cretaceous lower vertebrates from Galve (Teruel), Spain. Journal of Vertebrate Palaeontology. 2(1), 9-20.

unnamed Troodontidae (Antunes and Sigogneau-Russell, 1992)
Maastrichtian, Late Cretaceous
Unnamed unit, Distrito do Coimbra, Portugal
Material
- (AV 7) fragmentary tooth
(TV 43) fragmentary tooth
(TV 52) fragmentary tooth
Reference- Antunes and Sigogneau-Russell, 1992. La Faune de Petits Dinosaures du Cretace Terminal Portugais. Comun. Serv. Geol. Portugal. 78(1), 49-62.

unnamed troodontid (Dong, 1997)
Barremian-Albian, Early Cretaceous
Xinminbao Group, Gansu, China
Material
- (IVPP V11119) two teeth, two caudal vertebrae, partial tibia, distal tarsal, incomplete metatarsal II, phalanx II-1 (17 mm), phalanx II-2 (13 mm), pedal ungual II (9 mm), distal metatarsal III, phalanx III-1, partial metatarsal IV, phalanx IV-1
Comments- Dong (1997) referred this to Sinornithoides sp. nov. based on undescribed distal tarsal similarities, subequal size, and the plesiomorphically limited proximal extent of the distal articular surface on metatarsal III. However, he notes the less robust metatarsal IV differs. This suggests the specimen was outside the Sinornithoides+Troodon clade and should not be referred to the former genus. The teeth are said to have serrations (though smaller than derived troodontids), suggesting the taxon is closer to Troodon than Sinovenator or Mei.
Reference- Dong, 1997. On small theropods from Mazongshan Area, Gansu Province, China. Pp. 13-18. in Dong (ed). Sino-Japanese Silk Road Dinosaur Expedition. China Ocean Press, Beijing. 114 p.

undescribed possible troodontid (Xu and Norell, 2006)
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Material- specimen including integument
Reference- Xu and Norell, 2006. Non-avian dinosaur fossils from the Lower Cretaceous Jehol Group of western Liaoning, China. Geological Journal. 41(3-4), 419-437.

undescribed troodontid (Kobayashi, Lu, Lee, Xu and Zhang, 2008)
Late Cretaceous
Qiupa Formation, Henan, China

Comments- Note this is not the subsequently described Xixiasaurus, which is from the Majiacun Formation in Xixia County near Songgou village, not the Qiupa Formation in Luanchuan County near Qiupa village.
Reference- Kobayashi, Lu, Lee, Xu and Zhang, 2008. A new basal ornithomimid (Dinosauria: Theropoda) from the Late Cretaceous in Henan province of China. Journal of Vertebrate Paleontology. 28(3), 101A.

unnamed troodontid (Zhao, 2003)
Cenomanian, Late Cretaceous
Liantoutang Formation, Zhejiang, China
Material
- (ZMNH M8711) two nests of five and fourteen eggs
Comments- These are referred to the ootaxon Prismatoolithus sp..
References- Zhao, 2003. The nesting behavior of troodontid dinosaurs. Vertebrata PalAsiatica. 41, 157-168.
Varricchio, Jin and Jackson, 2015. Lay, brood, repeat: Nest reuse and site fidelity in ecologic time for two Cretaceous troodontid dinosaurs. Journal of Vertebrate Paleontology. 35(3), e932797. DOI: 10.1080/02724634.2014.932797

unnamed possible troodontid (Mathur and Srivastava, 1987)
Maastrichtian, Late Cretaceous
Lameta Formation, India
Material
- (GSI 19996) tooth
Comments- This was listed by Mathur and Srivastava (1987) as (?) Megalosaurus type E.
Reference- Mathur and Srivastava, 1987. Dinosaur teeth from Lameta Group (Upper Cretaceous) of Kheda District, Gujarat. Journal of the Geological Society of India. 29, 554-566.

Mei Xu and Norell, 2004
M. long Xu and Norell, 2004
Early Aptian, Early Cretaceous
Lujiatun Beds of Yixian Formation, Liaoning, China

Holotype- (IVPP V12733; ?= IVPP V12744 of Xu et al. 2014) (530 mm; subadult) incomplete skull (53 mm), sclerotic plates, incomplete mandible (56 mm), ten cervical vertebrae (67 mm), dorsal vertebrae (92 mm), dorsal ribs, gastralia, sacrum (30 mm), caudal vertebrae (257 mm), chevrons, scapulae (45 mm), coracoids (11 mm), furcula, sternal rib fragments(?), humeri (42 mm), radii (39 mm), ulnae (42 mm), semilunate carpal, (manus 67 mm) metacarpal I, phalanx I-1, manual ungual I, metacarpal II, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-2, phalanx III-3, manual ungual III, ilia, pubes, ischium, femora (81 mm), tibiae (106 mm), fibula, astragali, distal tarsals, metatarsal I, phalanx I-1, pedal ungual I, metatarsal II (51 mm), phalanx II-1, phalanx II-2, pedal ungual II, metatarsal III (58 mm), phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, metatarsal IV (55 mm), phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, metatarsal V
Referred- (DNHM D2514) (~325 mm; ~420 g; adult) incomplete skull (~49 mm), mandible, fragmentary fourth cervical vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh cervical vertebra, eighth cervical vertebra, ninth cervical vertebra, tenth cervical vertebra, incomplete eleventh cervical vertebra, cervical ribs, first dorsal neural arch, second dorsal neural arch, third dorsal neural arch, fourth dorsal neural arch, fifth dorsal neural arch, incomplete eighth dorsal vertebra, incomplete ninth dorsal vertebra (5.8 mm), incomplete tenth dorsal vertebra (6 mm), incomplete eleventh dorsal vertebra (5.9 mm), incomplete twelfth dorsal vertebra (5.9 mm), incomplete thirteenth dorsal vertebra, dorsal rib fragments, sacrum (22.2 mm), first caudal vertebra, second caudal vertebra, third caudal vertebra, fourth caudal vertebra (4 mm), fifth caudal vertebra (4 mm), sixth caudal vertebra (4.3 mm), seventh caudal vertebra (4.9 mm), eighth caudal vertebra (5.5 mm), ninth caudal vertebra (8 mm), tenth caudal vertebra (10.3 mm), eleventh caudal vertebra (11.1 mm), twelfth caudal vertebra (11 mm), thirteenth caudal vertebra (11.2 mm), fourteenth caudal vertebra (10.9 mm), fifteenth caudal vertebra (10.9 mm), sixteenth caudal vertebra (10.6 mm), seventeenth caudal vertebra (10.6 mm), eighteenth caudal vertebra, eleven chevrons, scapulae (36, 40 mm), coracoid, humeri (36 mm), radii (one incomplete), ulnae (one incomplete; ~34 mm), metacarpal I (4 mm), phalanx I-1 (14 mm), manual ungual I (7.3 mm), metacarpal II (13 mm), phalanx II-1 (7.8 mm), phalanx II-2 (13 mm), manual ungual II, metacarpal III (14.3 mm), phalanx III-1 (8.1 mm), phalanx III-2 (8.1 mm), phalanx III-3 (10.7 mm), ilia (34.4 mm), proximal pubes, femora (~65 mm), tibiotarsi (~86.1 mm), fibulae, distal metatarsal II (~42.5 mm), phalanx II-2, pedal ungual II, distal metatarsal III (~49 mm), phalanx III-1 (12.8 mm), phalanx III-3, metatarsals IV (one distal; 45.7 mm), phalanx IV-1 (8.4 mm), phalanx IV-2 (6.4 mm), phalanx IV-3 (5.9 mm), phalanx IV-4 (5.2 mm), metatarsal V (11 mm) (Gao et al., 2012)
Diagnosis- (after Xu and Norell, 2004) extremely large external nares extending posteriorly over one half of the maxillary tooth row; closely packed middle maxillary teeth; maxillary tooth row extending posteriorly to the level of the preorbital bar; robust U-shaped furcula; most proximal end of the pubic shaft is significantly compressed anteroposteriorly, and extends laterally just ventral to the articulation with the ilium; lateral process on distal tarsal IV.
(after Gao et al., 2012) posterior sacrum extremely wide with elongate fourth and fifth transverse processes; ilium strongly sigmoid in dorsal view, with a stronger lateral curve than in Velociraptor or Anchiornis.
References- Xu and Norell, 2004. A new troodontid dinosaur from China with avian-like sleeping posture. Nature. 431, 838-841.
Gao, Morschhauser, Varricchio, Liu and Zhao, 2012. A second soundly sleeping dragon: New anatomical details of the Chinese troodontid Mei long with implications for phylogeny and taphonomy. PLoS ONE. 7(9), e45203.
Xu, Han and Zhao, 2014. Homologies and homeotic transformation of the theropod 'semilunate' carpal. Nature Scientific Reports. 4, 6042.

Sinovenator Xu, Norell, Wang, Makovicky and Wu, 2002
S. changii Xu, Norell, Wang, Makovicky and Wu, 2002
Early Aptian, Early Cretaceous
Lujiatun Beds of Yixian Formation, Liaoning, China

Holotype- (IVPP V12615) (adult) incomplete skull (~90 mm), dentary, supradentary, surangulars, anterior cervical vertebra, mid cervical vertebra, mid cervical vertebra, posterior cervical vertebra, third dorsal vertebra (9.8 mm), fourth dorsal vertebra (9.8 mm), fifth dorsal vertebra (10 mm), sixth dorsal vertebra (10.2 mm), seventh dorsal vertebra (10.9 mm), eighth dorsal vertebra (11.2 mm), ninth dorsal vertebra (11.6 mm), tenth dorsal vertebra (11.7 mm), eleventh dorsal vertebra (11.3 mm), twelfth dorsal vertebra, fragmentary thirteenth dorsal vertebra, two partial dorsal ribs, sacrum, first caudal vertebra (7.2 mm), second caudal vertebra (8 mm), third caudal vertebra (10 mm), fourth caudal vertebra (10 mm), fifth caudal vertebra (10.2 mm), sixth caudal vertebra (~10.2 mm), incomplete scapula (~66 mm), coracoid, distal humerus, partial radius, partial ulna, metacarpal, manual ungual, ilium (~60 mm), pubes (97, 94 mm), ischium (40 mm), femur (117.5 mm), tibia (152.9 mm), incomplete fibulae, astragalus, metatarsal I (~19 mm), metatarsal II (77 mm), phalanx II-2, pedal ungual II, metatarsal III (86.2 mm), metatarsals IV (82.6, 83.4 mm), partial metatarsal V
Paratype- (IVPP V12583) (subadult) sacrum, first caudal vertebra (7 mm), second caudal vertebra (8.2 mm), third caudal vertebra (8 mm), fourth caudal vertebra (8 mm), fifth caudal vertebra (8 mm), sixth caudal vertebra (8 mm), seventh caudal vertebra (8.6 mm), eighth caudal vertebra (10 mm), ninth caudal vertebra (10.9 mm), tenth caudal vertebra (14.5 mm), eleventh caudal vertebra (16.1 mm), twelfth caudal vertebra (19 mm), thirteenth caudal vertebra, fourteenth caudal vertebra (18 mm), fifteenth caudal vertebra (18 mm), sixteenth caudal vertebra (20 mm), seventeenth caudal vertebra (19 mm), eighteenth caudal vertebra (18 mm), nineteenth caudal vertebra (17.9 mm), twentieth caudal vertebra (17.5 mm), twenty-first caudal vertebra (17.2 mm), twenty-second caudal vertebra (17.9 mm), twenty-third caudal vertebra (19 mm), twenty-fourth caudal vertebra (19 mm), twenty-fifth caudal vertebra (18.5 mm), twenty-sixth caudal vertebra (17.5 mm), proximal scapulae, fragmentary coracoids, humeri (71 mm), radius (~87 mm), ulna (91 mm), semilunate carpal, distal carpal III, metacarpal I (12 mm), phalanx I-1 (28 mm), metacarpal II (28.5 mm), two manual phalanges, pubis (87 mm), ischium (42.5 mm), femur (105 mm), tibiotarsi (148, 146 mm), fibulae, metatarsal II (79 mm), phalanges II-1 (15, 15 mm), phalanges II-2 (10, 10 mm), metatarsal III (91.7 mm), phalanges III-1 (21.5, 22 mm), phalanx III-2 (14.6 mm), phalanx III-3 (~13.5 mm), metatarsal IV (88 mm), phalanges IV-1 (15, 14.7 mm), phalanges IV-2 (12, 12.8 mm), phalanx IV-3 (10.2 mm), phalanx IV-4 (10.2 mm), partial metatarsal V
Referred- (IVPP V14009) (adult) specimen including semilunate carpal, metacarpal I, metacarpal II and metacarpal III (Xu et al., 2014)
(IVPP V14322) mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, proximal humerus, manual phalanges, manual unguals, pubis, ischium, femora, tibiae, partial fibula, astragalus, calcaneum, metatarsal II, phalanx II-1, phalanx II-2, pedal ungual II, metatarsal III, phalanx III-1, phalanx III-2, metatarsal IV, phalanx IV-1, phalanx IV-2 (Manabe, 2005)
(IVPP coll.) femur (206 mm), tibia (147 mm), metatarsal II, phalanx II-1, phalanx II-2, metatarsal III (92 mm), phalanx III-1, phalanx III-2, phalanx III-3 metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV (White, 2009)
? skull, cervical vertebrae, dorsal ribs, sacral vertebrae, caudal vertebrae, scapula, humerus, radius, ulna, manus, ilia, femur, tibiae, fibula, pes (Fossil Mall online)
Diagnosis- (after Xu et al., 2002) straight and vertical anterior margin of antorbital fenestra; frontal with a vertical lamina bordering the lacrimal; surangular T-shaped in cross-section; prominent lateral cnemial crest continuous with the fibular crest.
Comments- Creisler (DML 2002) noted Sinovenator changii was named after a woman, so suggested it be emended to S. changiae, which is followed on several websites. However, the Fourth Edition of the ICZN no longer requires emendations based on this reasoning (Article 31.1.3). If Sinovenator "changiae" is ever published, ICZN Article 32.2.3 states it will become an available name with its own authorship, though an objective junior synonym of S. changii.
The holotype and paratype were discovered in 2001 and named and briefly described by Xu et al. (2002). A more detailed description is in Xu's (2002) thesis, but has not yet been published.
Senter (2007) mentioned an undescribed specimen whose photo is available on www.dinosaur.net.cn. This is IVPP V14322, and is illustrated in Manabe (2005).
White (2009) describes and illustrates the pes of an unregistered specimen at the IVPP as Sinovenator sp.
An undescribed basically complete specimen is referred to Sinovenator on the Fossil Mall website, but may be at least partially faked due to its apparent lumbar region and non-maniraptoran forelimb position.
Senter et al. (2004) corrected Xu et al.'s description of several characters, finding the teeth to be unserrated, the antorbital fossa to lack a prominent rim, the anterior and posterior dentary teeth to be subequal in size and density, and the fourth metatarsal to be subequal in diameter to the second. Senter (2007) later corrected his account of dentary tooth density, agreeing with Xu et al. that the anterior teeth were more densely packed.
References- Xu, Norell, Wang, Makovicky and Wu, 2002. A basal troodontid from the Early Cretaceous of China. Nature. 415, 780-784.
http://dml.cmnh.org/2002Feb/msg00579.html
Xu, 2002. Deinonychosaurian fossils from the Jehol Group of Western Liaoning and the coelurosaurian evolution. PhD Thesis. Chinese Academy of Sciences. 325 pp.
http://www.dinosaur.net.cn/_Kyohaku2004/show_fly.htm
Senter, Barsbold, Britt and Burnham, 2004. Systematics and evolution of Dromaeosauridae. Bulletin of Gunma Natural History Museum. 8, 1-20.
Manabe, 2005, The Dinosaur expo 2005. 151pp.
Senter, 2007. A new look at the phylogeny of Coelurosauria. Journal of Systematic Palaeontology.
http://www.fossilmall.com/Science/Sites/China/Sinovenator/Sinovenator.jpg
White, 2009. The subarctometatarsus: intermediate metatarsus architecture demonstrating the evolution of the arctometatarsus and advanced agility in theropod dinosaurs. Alcheringa. 33(1), 1-21.
Xu, Han and Zhao, 2014. Homologies and homeotic transformation of the theropod 'semilunate' carpal. Nature Scientific Reports. 4, 6042.
Ma and Rayfield, 2015. Reconstructing the cranial musculoskeletal anatomy of two maniraptoran theropod dinosaurs and implications for avian evolution. Journal of Vertebrate Paleontology. Program and Abstracts 2015, 170.

undescribed troodontid (Hwang, Norell, Ji and Gao, 2004)
Early Aptian, Early Cretaceous
Lujiatun Beds of Yixian Formation, Liaoning, China

Material- (CAGS-IG01-004) incomplete skeleton including skull
Comments- This taxon shows small teeth with constricted bases and carinae lacking serrations, an apparently absent postorbital, and no quadratojugal-squamosal contact. It may be another specimen of Mei, and is said to be very similar to IGM 100/1323.
Reference- Hwang, Norell, Ji and Gao, 2004. A new troodontid from the lower Yixian Formation of China and its affinities to Mongolian troodontids. Journal of Vertebrate Paleontology. 24(3), 26A.

Geminiraptor Senter, Kirkland, Bird and Bartlett, 2010
G. suarezarum Senter, Kirkland, Bird and Bartlett, 2010
Barremian, Early Cretaceous
Yellow Cat Member of Cedar Mountain Formation, Utah, US
Holotype
- (CEUM 73719) partial maxilla
Diagnosis- (after Senter et al., 2010) maxilla with extensive pneumatization internal to antorbital fossa, inflating the bone so that it has a triangular cross-section; large, anteroposteriorly elongate maxillary fenestra; promaxillary fenestra visible in lateral view; anteroposteriorly narrow promaxillary strut and interfenestral strut; small, square dental alveoli with bony septa between them.
Comments- The holotype is incorrectly listed as CEUM 7319 in the paper (Carpenter, online 2010).
Senter et al. (2010) used a version of the TWG matrix to place Geminiraptor as a troodontid more derived than Sinovenator, but less than Saurornithoides+Troodon.
References- Senter, Kirkland, Bird and Bartlett, 2010. A new troodontid theropod dinosaur from the Lower Cretaceous of Utah. PLoS ONE. 5(12), e14329.
Senter, Kirkland, Deblieux and Madsen, 2010. Three new theropods from the Cedar Mountain Formation (Lower Cretaceous) of Utah. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 162A.

undescribed troodontid (Dufeau, 2003)
Late Campanian, Late Cretaceous
Djadokhta Formation, Mongolia

Material- (IGM 100/1128; = IGM 100/1005) skull, mandible, sacrum, twelve caudal vertebrae, distal radius, distal ulna, caprus, metacarpal I, distal phalanx I-1, manual ungual I, metacarpal II, phalanx II-1, phalanx II-2, manual ungual II, metacarpal III, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, ilia, femora (84 mm), tibiae, fibula, metatarsus, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, phalanx IV-1, phalanx IV-2
Comments- This specimen was collected from Ukhaa Tolgod in 1997. In the Fighting Dinosaurs: New Discoveries from Mongolia exhibit at the AMNH in 2000, it was displayed with troodontid postcrania. It is mislabeled on the AMNH website as the Shuvuuia holotype, though it differs in many respects from that taxon. A braincase analyzed by Franzosa (2004) as the Zos Canyon troodontid and labeled IGM 100/1005 is the same specimen, as Dufeau (2003) includes a photo of the skull labeled "IGM 100/1005 Undescribed troodontid". Hwang et al. (2004) refer to a second Ukhaa Tolgod basal troodontid skull (in addition to IGM 100/1323), which based on their description I infer to be this specimen. Erickson et al. (2009) examined the femur of an undescribed troodontid they call IGM 100/1129, which is probably a misprint for this same specimen. Similarly, Turner et al. (2011 and 2012) mislabel it IGM 100/1126, though Turner (2008) gets it right. Personal observation confirms the skull is labeled IGM 100/1128. The specimen was included in Turner's recent analysis (2008; et al., 2011 and 2012), where it emerged as a jinfengopterygine troodontid along with IGM 100/1323.
References- http://paleo.amnh.org/gobi/gobi.swf
Dufeau, 2003. The cranial anatomy of the theropod dinosaur Shuvuuia deserti (Coelurosauria: Alvarezsauridae), and its bearing upon coelurosaurian phylogeny. Unpublished Masters Thesis. The University of Texas at Austin. 275 pp.
Franzosa, 2004. Evolution of the Brain in Theropoda (Dinosauria). PhD Thesis. The University of Texas at Austin. 357 pp.
Hwang, Norell, Ji and Gao, 2004. A new troodontid from the lower Yixian Formation of China and its affinities to Mongolian troodontids. Journal of Vertebrate Paleontology. 24(3), 73A-74A.
Turner, 2008. Phylogenetic relationships of paravian Theropods. PhD Thesis. Columbia University. 666 pp.
Erickson, Rauhut, Zhou, Turner, Inouye, Hu and Norell, 2009. Was dinosaurian physiology inherited by birds? Reconciling slow growth in Archaeopteryx. PLoS ONE. 4(10), e7390.
Turner, Pol and Norell, 2011. Anatomy of Mahakala omnogovae (Theropoda: Dromaeosauridae), Tögrögiin Shiree, Mongolia. American Museum Novitates. 3722, 66 pp.
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and paravian phylogeny. Bulletin of the American Museum of Natural History. 371, 1-206.

undescribed troodontid (Hwang, Norell, Ji and Gao, 2004)
Late Campanian, Late Cretaceous
Djadokhta Formation, Mongolia

Material- (IGM 100/1323) specimen including skull and femur (80 mm)
Comments- This taxon is supposedly very similar to CAGS-IG01-004 in having teeth of the same number and morphology, and a modified diapsid configuration. Hwang (2005; 2007) describes the tooth morphology, while Erickson et al. (2009) examined femoral histology. Hwang (2007) also coded it in a TWG analysis, finding it to emerge sister to Byronosaurus. Turner (2008; published as Turner et al., 2012) also included it in a TWG analysis, finding it to emerge with Jinfengopteryx and IGM 100/1128 as a jinfengopterygine troodontid. This was also found in the related unpublished version shown in Turner et al. (2011).
References- Hwang, Norell, Ji and Gao, 2004. A new troodontid from the lower Yixian Formation of China and its affinities to Mongolian troodontids. Journal of Vertebrate Paleontology. 24(3), 73A-74A.
Hwang, 2005. Phylogenetic patterns of enamel microstructure in dinosaur teeth. Journal of Morphology. 266(2), 208-240.
Hwang, 2007. Phylogenetic patterns of enamel microstructure in dinosaur teeth. PhD Thesis. Columbia University. 274 pp.
Turner, 2008. Phylogenetic relationships of paravian Theropods. PhD Thesis. Columbia University. 666 pp.
Erickson, Rauhut, Zhou, Turner, Inouye, Hu and Norell, 2009. Was dinosaurian physiology inherited by birds? Reconciling slow growth in Archaeopteryx. PLoS ONE. 4(10), e7390.
Turner, Pol and Norell, 2011. Anatomy of Mahakala omnogovae (Theropoda: Dromaeosauridae), Tögrögiin Shiree, Mongolia. American Museum Novitates. 3722, 66 pp.
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and paravian phylogeny. Bulletin of the American Museum of Natural History. 371, 1-206.

unnamed troodontid (Tsuihiji, Barsbold, Watabe, Tsogtbaatar, Suzuki and Hattori, 2015)
Barremian-Albian?, Early Cretaceous
Khamaryn Ar, Mongolia
Material
- (IGM 100/140) thirteen distal caudal vertebrae, five distal chevrons, distal radius, distal ulna, radiale, semilunate carpal, metacarpal I (13.9 mm), phalanx I-1 (30.7 mm), manual ungual I (20.4 mm), metacarpals II (one incomplete, one distal), phalanges II-1 (18.8 mm), phalanges II-2 (30.1, 30.7 mm), manual unguals II (22.9, 23.2 mm), metacarpals III (one incomplete, one distal), phalanges III-1 (7.2 mm), phalanges III-2 (9.2 mm), phalanges III-3 (19.1 mm), manual unguals III (18.5 mm), manual claw sheaths, phalanx I-1 (11.5 mm), pedal ungual I (12 mm), partial metatarsal II, phalanx II-1 (20.4 mm), phalanx II-2 (14.9 mm), incomplete pedal ungual II, partial metastarsal III, phalanx III-1 (25.6 mm), phalanx III-2 (18 mm), phalanx III-3 (16.9 mm), incomplete pedal ungual III, incomplete metatarsal IV, phalanx IV-1 (16.8 mm), phalanx IV-2 (15.1 mm), phalanx IV-4 (13.7 mm), incomplete pedal ungual IV
Comments- This specimen was added to a TWG analysis by Tsuihiji et al. (2015) and found to be more derived than Byronosaurus.
Reference- Tsuihiji, Barsbold, Watabe, Tsogtbaatar, Suzuki and Hattori, 2015. New material of a troodontid theropod (Dinosauria: Saurischia) from the Lower Cretaceous of Mongolia. Historical Biology. 28(1-2), 128-138.

unnamed troodontid (Barsbold, Osmolska and Kurzanov, 1987)
Aptian-Albian, Early Cretaceous
Barunbayaskaya (or Huhteeg?) Svita, Mongolia

Material- (IGM 100/44) quadrate, baincase fragment, dentary fragment, posterior mandible, four teeth (2.5-3 mm), five partial cervical neural arches (22-25 mm), semilunate carpal, metacarpal I (15 mm), phalanx I-1 (36 mm), manual ungual I (18 mm), metacarpal II (40 mm), phalanx II-1 (26 mm), incomplete phalanx II-2 (24 mm), manual ungual II, metacarpal III (~37 mm), manual ungual III, distal femur, metatarsal I (13 mm), phalanx I-1 (13 mm), distal metatarsal II, phalanx II-1 (25 mm), phalanx II-2 (17 mm), pedal ungual II (~20 mm), distal metatarsal III (~108 mm), phalanx III-1 (29 mm), phalanx III-2 (17 mm), phalanx III-3 (~12 mm), distal metatarsal IV, phalanx IV-1 (19 mm), phalanx IV-2 (~13 mm), pedal ungual IV fragment
Reference- Barsbold, Osmolska and Kurzanov, 1987. On a new troodontid (Dinosauria, Theropoda) from the Early Cretaceous of Mongolia. Acta Palaeontologica Polonica. 32(1-2), 121-132.

undescribed troodontid (Hartman, Lovelace and Wahl, 2005)
Late Kimmeridgian, Late Jurassic
Brushy Basin Member of the Morrison Formation, Wyoming, US
(WDC DML quarry)
Material- (WDC DML0001; Lori) (~1.5 m; adult) incomplete skull, incomplete mandible, hyoids, four cervical vertebrae (17.3 mm), cervical rib, dorsal vertebra, several partial dorsal ribs, twelve caudal vertebrae (mid caudal 22.8 mm), four chevrons, partial scapula, partial coracoid, partial furcula, incomplete humerus (~57.7 mm), distal radius, distal ulna (27 mm), radiale, semilunate carpal, metacarpal I (16.1 mm), manual ungual I, metacarpal II, manual ungual II, metacarpal III, partial phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, ilial fragment, incomplete femur (~93.4 mm), tibiae (160 mm inc. tarsus), fibulae, astragalus, calcaneum, distal tarsal, metatarsal II, metatarsal III (57.1 mm), phalanx III-1 (29 mm), phalanx III-2 (28 mm), pedal ungual III, metatarsal IV, phalanx IV-1, phalanx IV-2 (12 mm), phalanx IV-3 (9.1 mm), phalanx IV-4 (7.7 mm), metatarsal V
Comments- This specimen was discovered in 2001 and announced in an abstract (Lovelave, 2004). In Hartman et al.'s (2005) preliminary analysis, it emerged sister to Sinornithoides.
References- Lovelace, 2004. Taphonomy and paleoenvironment of a Late Jurassic dinosaur locality in the Morrison Formation of east-central Wyoming. Journal of Vertebrate Paleontology. 24(3), 152A.
Hartman, Lovelace and Wahl, 2005. Phylogenetic assessment of a maniraptoran from the Morrison Formation. Journal of Vertebrate Paleontology. 25(3), 67A-68A.
Wahl, 2006. Osteology and phylogenetic relationships of a new small maniraptoran from the Upper Jurassic of Wyoming. MS Thesis, Fort Hays State University.

unnamed troodontid (Currie, Rigby and Sloan, 1990)
Late Campanian, Late Cretaceous
Dinosaur Park Formation of the Judith River Group, Alberta, Canada

Material- (RTMP 79.8.635) tooth (3.3 mm) (Currie, Rigby and Sloan, 1990)
(RTMP 85.30.1) tooth (Currie, Rigby and Sloan, 1990)
(RTMP 2000.19.1) tooth (5.5 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 2000.20.1) tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 2000.21.11) tooth (5.2 mm) (Sankey, Brinkman, Guenther and Currie, 2002)
Late Maastrichtian, Late Cretaceous
Lance Formation, Montana, Wyoming, US
(AMNH 8114) tooth (Estes, 1964)
?(AMNH 27117) eleven teeth (Estes, 1964; AMNH online)
Diagnosis- (after Sankey et al., 2002) tooth crowns flattened or concave on one side; enamel pitted on flat/concave side; two well-developed longitudinal ridges present on flat surface, one ridge extending from the apex denticle to near the base of the enamel and the second extending along the anterior carina; mesial serrations always absent; distal serrations rounded.
Comments- This tooth morphology was considered a pathological varient of Troodon formosus by Currie et al. (1990), who referred to it as "Paronychodon" (Troodon). Sankey et al. (2002) considered it a valid taxon though, based on its differing temporal and spatial distribution than Troodon formosus. Specifically, this taxon is restricted to the upper Dinosaur Park Formation within the Judith River Group, and has not been reported from the Prince Creek Formation where T. formosus is common. Sankey et al. also referred teeth described by Estes (1964) as cf. Saurornithoides sp. from the Lance Formation to this species, based on figured specimen AMNH 8114. Troodon bakkeri from that formation is not the same as this taxon, as it has pointed distal serrations like Troodon formosus. It's highly possible additional Late Cretaceous North American teeth currently identified as Troodon belong to this taxon.
References- Estes, 1964. Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming. University of California Publications in Geological Sciences. 49, 1-180.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

unnamed Troodontidae (Novikov, Lebedev and Alifanov, 1998)
Aptian-Albian, Early Cretaceous
Ilek (=Shestakovo) Formation, Russia
Material
- (PM TGU 16/5-124) maxillary or posterior dentary tooth
(PM TGU coll.) caudal vertebra, metacarpal I
(lost) fragmentary skeleton including jaw element, teeth, tarsus (Alifanov et al., 1999)
References- Novikov, Lebedev and Alifanov, 1998. New Mesozoic vertebrate fossil sites of Russia. Third European Workshop on Vertebrate Paleontology, Maastricht, 6-9 May 1998, p. 58.
Alifanov, Efimov, Novikov and Morales, 1999. [A new psittacosaur complex of tetrapods from the Lower Cretaceous Shestakovo locality (southern Siberia).] Doklady Akademii Nauk. 369(4), 491–493. [Russian]
Alifanov, Efimov, Novikov and Morales, 1999. A new psittacosaurian complex of tetrapods from the Lower Cretaceous Shestakovo locality (Southern Siberia). Doklady Earth Sciences. 369A(9), 1228–1230.
Leshchinskiy, Voronkevich, Fayngertz, Maschenko, Lopatin and Averianov, 2001. Early Cretaceous vertebrate locality Shestakovo, Western Siberia, Russia: A refugium for Jurassic relicts? Journal of Vertebrate Paleontology. 21(3), 73A.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.

unnamed possible troodontid (Grigorescu, Hartemberger, Radulescu, Samson and Sudre, 1985)
Late Maastrichtian, Late Cretaceous
Sinpetru Beds, Romania
Material
- (FGGUB R.1318) tooth (12.5 mm)
(FGGUB R.1319) tooth (11 mm)
(FGGUB R.1320) tooth (5.3 mm)
(MAFI v.12685) tooth (11.2 mm), tooth (8 mm)
Comments- These teeth are most similar to Koparion in having constricted roots, blood pits and enlarged serrations (~5/mm) which are present on both carinae, yet not enlarged to the extent seen in Saurornithoides and Troodon, nor apically hooked. They differ in being much larger and less recurved, with flat distal serrations.
References- Grigorescu, Hartemberger, Radulescu, Samson and Sudre, 1985. Decouverte de Mammiferes et Dinosaures dans le Cretace superieur de Pui (Roumanie). Compte rendu hebdomadaire des seances de l’Academie des Sciences Paris. 301, 2(19), 1365-1368.
Csiki and Grigorescu, 1998. Small Theropods from the Late Cretaceous of the Hateg Basin (Western Romania) - an unexpected diversity at the top of the food chain. Oryctos. 1, 87-104.

undescribed possible troodontid (Debeljak, Kosir and Otonicar, 1999)
Campanian-Maastrichtian, Late Cretaceous
Kozina, Slovenia
Material
- (ACKK-D-8/088) tooth
References- Debeljak, Kosir and Otonicar, 1999. A preliminary note on dinosaurs and non-dinosaurian reptiles from the Upper Cretaceous carbonate platform succession at Kozina (SW Slovenia). Razprave IV. razreda SAZU. 40, 3-25.
Debeljak, Kosir, Buffetaut and Otonicar, 2002. The Late Cretaceous dinosaurs and crocodiles of Kozina (SW Slovenia): A preliminary study. Memorie della Societa Geologica Italiana. 57, 193-201.

unnamed troodontid (Dong, 1997)
Barremian-Albian, Early Cretaceous
Xinminbao Group, Gansu, China
Material
- (IVPP V11122-2) tooth
Comments- This short recurved tooth with a basal constriction was reported to have mesial and distal serrations. It was referred to Troodontidae. It may belong to the same taxon as IVPP V11119.
Reference- Dong, 1997. On small theropods from Mazongshan Area, Gansu Province, China. Pp. 13-18. in Dong (ed). Sino-Japanese Silk Road Dinosaur Expedition. China Ocean Press, Beijing. 114 p.

Koparion Chure, 1994
K. douglassi Chure, 1994
Late Kimmeridgian, Late Jurassic
Brushy Basin Member of the Morrison Formation, Utah, US

Holotype- (DINO 3353) maxillary tooth (2 mm)
Diagnosis- differs from Sinusonasus, Sinornithoides and "Saurornithoides" asiamericanus in having mesial serrations on lateral teeth; differs from Sinornithoides, "Saurornithoides" asiamericanus, Saurornithoides and Troodon in having comparatively smaller distal serrations; differs from "Saurornithoides" asiamericanus, Saurornithoides and Troodon in having distal serrations which are not hooked apically.
Comments- Although Chure no longer thinks Koparion is a troodontid (pers. comm. to Harris, 1997; in Naish, DML 1997), there are no other suggested phylogenetic placements which are supported by the evidence. Rauhut (2000) suggested it might be a compsognathid, but Compsognathus differs in lacking mesial serrations. Compsognathus-like teeth from Guimarota described by Zinke (1998) do have mesial serrations, but Koparion differs in having no blood pits, and less serrations per mm on both carinae (8 and 7 on mesial and distal vs. 10-17 and 10-15 in cf. Compsognathus) despite similar crown size. These are more similar to derived troodontids. The only other theropods with constricted tooth bases and serrated teeth are Richardoestesia-like taxa and therizinosaurs. Richardoestesia and related taxa differ in having highly elongate teeth with extremely numerous serrations with no blood pits. Therizinosauroids have much larger serrations (~3/mm in Beipiaosaurus and Alxasaurus), while Falcarius' serration size is comparable. However, maxillary teeth of Falcarius have convex distal edges with serrations smaller in comparison to tooth size. Smaller posterior dentary teeth are schematically illustrated as being more recurved, so may be more comparable to Koparion. Therizinosaurs also lack blood pits. Koparion differs from Sinusonasus in having mesial serrations, though they are similar in having small distal serrations without apically hooked tips. It differs from Sinornithoides and "Saurornithoides" asiamericanus in having comparatively smaller distal serrations (Currie and Dong, 2001), and having mesial serrations on non-premaxillary teeth. It further differs from "Saurornithoides" americanus in having distal serrations whose tips are not hooked.
References- Chure and Britt, 1993. New data on theropod dinosaurs from the Late Jurassic Morrison Fm. (MF). Journal of Vertebrate Paleontology. 13(3), 30A.
Chure, 1994. Koparion douglassi, a new dinosaur from the Morrison Formation (Upper Jurassic) of Dinosaur National Monument; The oldest troodontid (Theropoda: Maniraptora). Brigham Young University Geological Studies. 40, 11-15.
http://dml.cmnh.org/1997Jan/msg00325.html
Zinke, 1998. Small theropod teeth from the Upper Jurassic coal mine of Guimarota (Portugal). Palaontologische Zeitschrift. 72(1/2) 179-189.
Rauhut, 2000. The interrelationships and evolution of basal theropods (Dinosauria, Saurischia). Ph.D. dissertation, University of Bristol, Bristol. 583 pp.
Currie and Dong, 2001. New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People’s Republic of China. Canadian Journal of Earth Sciences. 38, 1753-1766.

"Saurornithoides" asiamericanus (Nessov, 1995) Olshevsky, 2000
= Pectinodon "asiamericanus" Nessov, 1985
= Saurornithoides "asiamericanus" (Nessov, 1985) Olshevsky, 1991
= Troodon asiamericanus Nessov, 1995
Early Cenomanian, Late Cretaceous
Khodzhakul Formation, Uzbekistan
Holotype
- (CCMGE 49/12176) posterior dentary tooth
Referred- (ZIN PH 1883/16) tooth (Averianov and Sues, 2016)
(ZIN PH 1884/16) tooth (Averianov and Sues, 2016)
(ZIN PH 1885/16) anterior dentary tooth (Averianov and Sues, 2007)
(ZIN PH 1886/16) anterior dentary tooth (Averianov and Sues, 2007)
(ZIN PH 1888/16) maxillary tooth (Averianov and Sues, 2007)
(ZIN PH 1889/16) tooth (Averianov and Sues, 2016)
(ZIN PH 1890/16) tooth (Averianov and Sues, 2016)
(ZIN PH 1891/16) tooth (Averianov and Sues, 2016)
?(ZIN PH 2355/16) distal caudal vertebra (Averianov and Sues, 2016)
?(ZIN PH 2356/16) distal caudal vertebra (Averianov and Sues, 2016)
?(ZIN PH 2357/16) distal caudal vertebra (Averianov and Sues, 2016)
?(ZIN PH 2358/16) distal caudal vertebra (Averianov and Sues, 2016)
Diagnosis- provisionally indeterminate relative to Sinornithoides.
Comments- The holotype tooth was originally distinguished from Troodon formosus by its smaller size, more labiolingually compressed crowns, unserrated mesial carina and smaller distal serrations (Nessov, 1995). However, these characters are also seen in more basal troodontids such as Sinornithoides and Sinusonasus (Averianov and Sues, 2004). The referred teeth are indistinguishable from the holotype.
References- Nessov, 1985. New mammals from the Cretaceous of the Kyzylkum. Vestnik Leningradskogo Universiteta. Seriya 7, 8-18.
Olshevsky, 1991. A Revision of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodylia. Mesozoic Meanderings #2 (1st printing): iv + 196 pp.
Nessov, 1995. Dinosaurs of nothern Eurasia: new data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg 1-156.
Olshevsky, 2000. An Annotated Checklist of Dinosaur Species by Continent. Mesozoic Meanderings #3: 1-157.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.
Averianov and Sues, 2016. Troodontidae (Dinosauria: Theropoda) from the Upper Cretaceous of Uzbekistan. Cretaceous Research. 59, 98-110.

Sinornithoides Russell and Dong, 1994
S. youngi Russell and Dong, 1994
Early Cretaceous
Ejinhoro Formation, Inner Mongolia, China
Holotype
- (IVPP V9612) (1.1 m) skull (109 mm), hyoid, atlantal neural arch, fourth cervical centrum (18 mm), fifth cervical vertebra (18 mm), sixth cervical prezygapophysis, ninth cervical vertebra (19.1 mm), ninth cervical rib, tenth cervical vertebra (14.4 mm), tenth cervical rib, first dorsal vertebra (13 mm), first dorsal rib, ten pairs of dorsal ribs, fifteen rows of gastralia, (sacrum- 72 mm) sixth sacral vertebra (12 mm), first caudal vertebra (~11.5 mm), first chevron (16.7 mm), second caudal vertebra (~13.5 mm), second chevron (23.8 mm), third caudal vertebra (14.5 mm), fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra, seventh caudal vertebra (11.6 mm), seventh chevron (9.2 mm), eighth caudal vertebra (14 mm), ninth caudal vertebra (17.5 mm), tenth caudal vertebra (21.2 mm), eleventh caudal vertebra (21.5 mm), twelfth caudal vertebra (23 mm), thirteenth caudal vertebra (24.5 mm), fourteenth caudal vertebra (23.9 mm), fifteenth caudal vertebra (23 mm), sixteenth caudal vertebra (22.5 mm), seventeenth caudal vertebra (23.5 mm), eighteenth caudal vertebra (22.9 mm), nineteenth caudal vertebra (24 mm), twentieth caudal vertebra (23.8 mm), twenty-first caudal vertebra (23 mm), twenty-second caudal vertebra (22 mm), twenty-third caudal vertebra (18 mm), twenty-fourth caudal vertebra (22.4 mm), twenty-fifth caudal vertebra (~20 mm), twenty-sixth caudal vertebra (~18 mm), twenty-seventh caudal vertebra (~16.8 mm), chevrons, proximal scapula, coracoids (~30 mm long, 27 mm deep), incomplete furcula, humeri (82.8 mm), radius (59.1 mm), ulna (65 mm), radiale, semilunate carpal, metacarpal I (11.3, 12.1 mm), phalanx I-1 (29.3 mm), manual ungual I (19.7 mm), metacarpal II (37.1 mm), phalanx II-1 (19 mm), phalanx II-2 (28.5, 28.1 mm), manual ungual II (22, 22 mm), metacarpal III (35 mm), phalanx III-1 (4.2 mm), phalanx III-2 (8.2 mm), phalanx III-3 (20.3 mm), manual ungual III (15.5 mm), ventral ilia (73 mm), pubes (89 mm), ischia (47.5 mm), femora (140 mm), tibiae (197.6 mm), fibulae, astragali (19.2 mm wide), distal tarsal III, distal tarsal IV, metatarsal I (~12.3, 12.3 mm), phalanx I-1 (11.4, 10 mm), pedal ungual I (10.7, 9.5 mm), metatarsal II (100.4, 100.6 mm), phalanx II-1 (20.2, 21.7 mm), phalanx II-2 (11.7 mm), pedal ungual II (19 mm), metatarsal III (111 mm), phalanx III-1 (27.6, 23 mm), phalanx III-2 (20, 19.2 mm), phalanx III-3 (16, 15.8 mm), pedal ungual III (14.6 mm), metatarsal IV (110 mm), phalanx IV-1 (17.8, 18.2 mm), phalanx IV-2 (15.7, 13.9 mm), phalanx IV-3 (13, 11.7 mm), phalanx IV-4 (12.5, 13 mm), pedal ungual IV (11.5 mm), metatarsal V (41.8 mm)
Comments- Note that while volume 30(10) of the Canadian Journal of Earth Sciences lists its date as October 1993, it was not published until February or March of 1994.
Dong (1997) referred a fragmentary specimen (IVPP V11119) to Sinornithoides sp. nov., but it seems to be more basal.
References- Russell and Dong, 1994. A nearly complete skeleton of a new troodont dinosaur from the Early Cretaceous of the Ordos Basin, Inner Mongolia, People's Republic of China. Canadian Journal of Earth Sciences. 30(10), 2163-2173.
Dong, 1997. On small theropods from Mazongshan Area, Gansu Province, China. Pp. 13-18. in Dong (ed). Sino-Japanese Silk Road Dinosaur Expedition. China Ocean Press, Beijing. 114 p.
Currie and Dong, 2001. New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People's Republic of China. Canadian Journal of Earth Sciences. 38, 1753-1766.
White, 2009. The subarctometatarsus: intermediate metatarsus architecture demonstrating the evolution of the arctometatarsus and advanced agility in theropod dinosaurs. Alcheringa. 33(1), 1-21.

Byronosaurus Norell, Makovicky and Clark, 2000
= "Byranjaffia" Novacek, 2002
B. jaffei Norell, Makovicky and Clark, 2000
Late Campanian, Late Cretaceous
Djadokhta Formation, Mongolia

Holotype- (IGM 100/983) partial skull, incomplete mandibles, posterior axis, incomplete third cervical vertebra, anterior fourth cervical vertebra, fourth cervical rib, two anterior dorsal centra, posterior dorsal vertebrae, dorsal rib fragment, possible sacral centrum, four distal caudal fragments, distal femur (~150 mm), proximal tibia, proximal fibula, limb bone fragments, distal metatarsal II, phalanx II-2, distal phalanx III-2, proximal phalanx III-3
Paratype- (IGM 100/984) premaxillae, anterior maxillae, maxillary fragment, lacrimals, posterior nasals, vomer fragment
Referred- ?(IGM 100/972) (juvenile) partial premaxillae, maxillae, nasals, lacrimals, incomplete jugals, anterior frontal, palatal elements, incomplete mandible (Norell, Clark, Demberelyin, Barsbold, Chiappe, Davidson, McKenna, Perle and Novacek, 1994)
?(IGM 100/974) (juvenile) incomplete skull, posterior mandible (Norell, Clark, Demberelyin, Barsbold, Chiappe, Davidson, McKenna, Perle and Novacek, 1994)
?(IGM 100/1003) (adult) tooth
....(juvenile) skeleton including cervical vertebrae, dorsal ribs, incomplete femora, tibiae, fibula, metatarsi, pedal phalanges, nineteen eggs, nest (Clark et al., 2002)
Diagnosis- (after Makovicky et al., 2003) teeth lacking serrations; interfenestral bar is not recessed from the plane of the maxilla; shallow groove along the buccal margin of the maxilla.
Comments- The holotype was discovered in 1993 and illustrated as an undescribed troodontid in Novacek et al. (1994). Its unassociated remains were mixed with those of ornithomimid specimen IGM 100/987. The paratype was found later in 1996. Novacek (2002) used the name "Byranjaffia" in his book for Byronosaurus. The former is either a misspelling or an unpublished name previously intended for the genus.
Baby Byronosaurus and nest? Two juvenile skulls were found associated with a Citipati nest (Norell et al., 1994). They were identified by Norell et al. as Velociraptor, based on their long premaxillae (on IGM 100/974 at least). However, Norell and Makovicky (1999) state that Norell et al. (in press) will show they are actually troodontids. This later became Bever and Norell (2008, 2009), who supported their assignment to Byronosaurus, as did Grellet-Tinner (2005) for 100/972 at least. However, Pei and Norell (2011) refer at least IGM 100/972 to their new troodontid (here tentatively referred to Gobivenator), based on (taller?) snout shape and less maxillary teeth compared to Byronosaurus, but these are juvenile characters expected in any nestling. Adding to the possibilities, Hwang et al. (2004) noted two additional troodontids from the Djadohkta with serrationless teeth, and embryonic Troodon lack serrations, so young individuals of the contemporaneous Saurornithoides might as well. Which taxon the nestlings belong to thus requires further study. Sues and Averianov (2007) mistakenly state IGM 100/974 was reidentified as an oviraptorid, and that the serrationless teeth were actually maxillary palatal bumps, but they were confusing it with embryonic Citipati specimen IGM 100/971.
Norton (DML, 2000) first stated IGM 100/1003 was on display at the AMNH's Fighting Dinosaurs exhibit. Clark et al. (2002) noted an undescribed nest with juveniles and an adult tooth as being the subject of an upcoming paper (Norell et al., in prep.). Only the eggs have so far been described, in Grellet-Tinner's (2005) thesis. Grellet-Tinner also determined eggshell attached to IGM 100/972's skull is the same as that from the eroded nest, and that 100/972 was found in the same location as 100/1003 but a few meters downhill. As neither 100/972 or 100/974 were in situ in the Citipati nest, it seems plausible they eroded out from 100/1003. If true, and Pei and Norell are correct that 100/972 is not Byronosaurus, this would eliminate referral of any nests or eggs to the latter genus.
References- Norell, Clark, Dashzeveg, Barsbold, Chiappe, Davidson, McKenna and Novacek, 1994. A theropod dinosaur embryo, and the affinities of the Flaming Cliffs dinosaur eggs. Science 266, 779-782.
Novacek, Norell, McKenna and Clark, 1994 Fossils of the Flaming Cliffs. Scientific American. 271(6), 60-69.
Norell and Makovicky, 1999. Important features of the dromaeosaurid skeleton II: information from newly collected specimens of Velociraptor mongoliensis. American Museum Novitates. 3282, 1-45.
Norell, Makovicky and Clark, 2000. A new troodontid theropod from Ukhaa Tolgod, Mongolia. Journal of Vertebrate Paleontology. 20(1), 7-11.
http://dml.cmnh.org/2000Jun/msg00082.html
Clark, Norell and Makovicky, 2002. Cladistic approaches to the relationships of birds to other theropod dinosaurs. in Chiappe and Witmer (eds.). Mesozoic Birds: Above the Heads of Dinosaurs. University of California Press. 31-64.
Novacek, 2002. Time Traveler: In search of dinosaurs and ancient mammals from Montana to Mongolia. Farrar, Strauss and Giroux, New York. 368 + xii pp.
Makovicky, Norell, Clark and Rowe, 2003. Osteology and relationships of Byronosaurus jaffei (Theropoda: Troodontidae). American Museum Novitates. 3402, 1-32.
Hwang, Norell, Ji and Gao, 2004. A new troodontid from the lower Yixian Formation of China and its affinities to Mongolian troodontids. Journal of Vertebrate Paleontology. 24(3), 73A–74A.
Grellet-Tinner, 2005. A phylogenetic analysis of oological characters: A case study of saurischian dinosaur relationships and avian evolution. PhD thesis, University of Southern California. 221 pp.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.
Bever and Norell, 2008. Neonate troodontid skulls from the Upper Cretaceous of Mongolia with observations on the cranial ontogeny of paravian theropods. Journal of Vertebrate Paleontology. 28(3), 52A.
Bever and Norell, 2009. The perinate skull of Byronosaurus (Troodontidae) with observations on the cranial ontogeny of paravian theropods. American Museum Novitates. 3657, 51 pp.
Erickson, Rauhut, Zhou, Turner, Inouye, Hu and Norell, 2009. Was dinosaurian physiology inherited by birds? Reconciling slow growth in Archaeopteryx. PLoS ONE. 4(10), e7390.
Pei and Norell, 2011. A new troodontid (Dinosauria: Theropoda) from the Late Cretaceous Djadokhta Formation of Mongolia. Journal of Vertebrate Paleontology. Program and Abstracts 2011, 172.

Tochisaurus Kurzanov and Osmolska, 1991
T. nemegtensis Kurzanov and Osmolska, 1991
Early Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia

Holotype- (PIN 551-224) (2.83 m) metatarsal II (233 mm), metatarsal III (232 mm), metatarsal IV (242 mm)
Diagnosis- (after Kurzanov and Osmolska, 1991) proximal surface of metatarsus inclined; strongly reduced metatarsal II.
Comments- This was originally figured by Kurzanov (1987) as an unknown theropod, then identified by Osmolska (1987) as a troodontid. Although Osmolska speculated it might be a specimen of Borogovia, Kurzanov and Osmolska (1991) noted the distal end of metatarsal II is far more reduced in Tochisaurus. Similarly, Tochisaurus differs from Zanabazar in having metatarsal II narrower proximally, and the proximal surface of the metatarsus inclined. It cannot be compared to the earlier Saurornithoides, however.
References- Kurzanov, 1987. Avimimidae and the problem of the origin of birds [in Russian]. Trudy, Sovmestnaa Sovetsko-Mongolskaa paleontologiceskaa ekspedicia. 31, 1-95.
Osmolska, 1987. Borogovia gracilicrus gen. et sp. n., a new troodontid dinosaur from the Late Cretaceous of Mongolia. Acta Palaeontologica Polonica. 32, 133-150.
Kurzanov and Osmólska, 1991. Tochisaurus nemegtensis gen. et sp. n., a new troodontid (Dinosauria, Theropoda) from Mongolia. Acta Palaeontologia Polonica. 36, 69-76.

Xixiasaurus Lu, Xu, Liu, Zhang, Jia and Ji, 2010
X. henanensis Lu, Xu, Liu, Zhang, Jia and Ji, 2010
Coniacian-Campanian, Late Cretaceous
Lower-Middle Majiacun Formation, Henan, China
Holotype-
(41HIII-0201) anterior skull, anterior dentary, radial fragment, ulnar fragment, phalanx I-1 (36 mm), manual ungual I, distal metacapal II, phalanx II-1 (30 mm), proximal phalanx II-2, distal metacarpal III, distal manual ungual
Diagnosis- (after Lu et al., 2010) distinct opening on the lateral surface of the base of the nasal process of the premaxilla; snout shows a more tapered U-shape than in Byronosaurus; 22 maxillary teeth; mandibular symphyseal region is slightly inflected medially.
Reference- Lu, Xu, Liu, Zhang, Jia and Ji, 2010. A new troodontid (Theropoda: Troodontidae) from the Late Cretaceous of Central China, and the radiation of Asian troodontids. Acta Palaeontologica Polonica. 55(3), 381-388.

Sinusonasus Xu and Wang, 2004
S. magnodens Xu and Wang, 2004
Early Aptian, Early Cretaceous
Lujiatun Beds of Yixian Formation, Liaoning, China

Holotype- (IVPP V 11527) (adult) incomplete skull (~109 mm), incomplete mandible, several dorsal ribs, gastralia, sacrum, twenty-seven caudal vertebrae (537 mm), chevrons, pubis (113 mm), ischia (61 mm), femur (141 mm), tibiae (186 mm), fibula (167 mm), metatarsal I (22.7, 19.9 mm), phalanx I-1 (10.2, 12.1 mm), pedal ungual I (15.7, 15.7 mm), metatarsal II (93.5 mm), phalanx II-1 (24.2, 21.2 mm) phalanx II-2 (17.6, 20.6 mm), pedal ungual II (31.1 mm), metatarsal III (~108 mm), phalanx III-1 (28.5 mm), phalanx III-2 (19.1 mm), phalanx III-3 (19.4 mm), pedal ungual III (13.6 mm), metatarsal IV (106.6 mm), phalanx IV-1, phalanx IV-2 (13.7 mm), phalanx IV-3 (14.7 mm), metatarsal V
Diagnosis- (after Xu and Wang, 2004) interantorbital canal absent; nasal sinusoid in lateral view; middle maxillary teeth relatively large; distal chevrons elongated to contact each other anteroposteriorly; femoral neck long.
Comments- This genus was consistantly mispelled Sinucerasaurus by Xu and Norell (2006), though the latter was written over a year after the publication of Sinusonasus.
Reference- Xu and Wang, 2004. A New Troodontid (Theropoda: Troodontidae) from the Lower Cretaceous Yixian Formation of Western Liaoning, China. Acta Geologica Sinica. 78(1), 22-26.
Xu and Norell, 2006. Non-avian dinosaur fossils from the Lower Cretaceous Jehol Group of western Liaoning, China. Geological Journal. 41(3-4), 419-437.

Gobivenator Tsuihiji, Barsbold, Watabe, Tsogtbaatar, Chinzorig, Fugiyama and Suzuki, 2014
G. mongoliensis Tsuihiji, Barsbold, Watabe, Tsogtbaatar, Chinzorig, Fugiyama and Suzuki, 2014
Campanian, Late Cretaceous
Djadochta Formation, Mongolia
Holotype
- (IGM 100/86) incomplete skull, incomplete mandible, proatlas, atlas, axis (14.6 mm), third to fourth cervical vertebrae, eighth to tenth cervical vertebrae, cervical ribs, twelve dorsal vertebrae (d1 24 mm, d12 21.6 mm), dorsal ribs, gastralia, synsacrum (205.4 mm), thirty-five caudal vertebrae (c1 15.8 mm, c34 19.4 mm), chevrons, scapula (107.9 mm), coracoids, humeri (108.9 mm), proximal radius, proximal ulna, incomplete ilium, pubis (169.4 mm), ischium (~92 mm), femur (~192 mm), proximal tibia, proximal fibula, astragalocalcaneum, metatarsal I, phalanx I-1, pedal ungual I, distal tarsal III, distal tarsal IV, metatarsal II (145.2 mm), phalanx II-1, phalanx II-2, metatarsal III (159.4 mm), metatarsal IV (163 mm), phalanx IV-1, metatarsal V
Referred- ? incomplete skull (~80 mm), dorsal ribs, sacral vertebrae, caudal vertebrae, chevrons, pelvis including ischium, partial hindlimbs (Pei and Norell, 2011)
Diagnosis- (after Tsuihiji et al., 2014) pointed anterior end of fused parietal that wedges into V-shaped notch between frontals; gracile anterior, posterior and ventral rami of postorbital; dorsoventrally elongated proximal chevrons (up to 4.5 times as long as the height of the preceding caudal vertebrae).
Comments- Pei and Norell (2011) reported a new troodontid from Ukhaa Tolgod with serrationless teeth, but distinguished from Byronosaurus due to its recessed interfenestral bar, less teeth and (taller?) snout shape. It also has proximal chevrons more than twice as long as their centra and a spike-like process on the anterior ischial edge. These characters are all shared with the contemporaneous and subsequently described troodontid Gobivenator, except for the seemingly taller skull. However, the latter is a juvenile character and Pei and Norell's specimen is only ~40% the size of the Gobivenator holotype. Pending publication of further details, it is provisionally placed as a young Gobivenator specimen here. They also refer supposed Byronosaurus nestling IGM 100/972 to their new taxon, based on (taller?) snout shape and less maxillary teeth compared to Byronosaurus, but these are juvenile characters expected in any nestling. Which taxon the nestling (and IGM 100/974) belong to thus requires further study.
References- Tsuihiji, Watabe, Tsogtbaatar, Suzuki and Barsbold, 2010. A new troodontid (Dinosauria: Theropoda) from the Late Cretaceous of the Gobi Desert, Mongolia. Journal of Vertebrate Paleontology. Program and Abstracts 2010, 177A-178A.
Pei and Norell, 2011. A new troodontid (Dinosauria: Theropoda) from the Late Cretaceous Djadokhta Formation of Mongolia. Journal of Vertebrate Paleontology. Program and Abstracts 2011, 172.
Tsuihiji, Barsbold, Watabe, Tsogtbaatar, Chinzorig, Fugiyama and Suzuki, 2014. An exquisitely preserved troodontid theropod with new information on the palatal structure from the Upper Cretaceous of Mongolia. Naturwissenschaften. 101, 131-142.

Philovenator Xu, Zhao, Sullivan, Tan, Sander and Ma, 2012
P. curriei Xu, Zhao, Sullivan, Tan, Sander and Ma, 2012
Late Campanian, Late Cretaceous
Wulansuhai Formation, Inner Mongolia, China
Holotype- (IVPP V10597) (~.68 m; 1.1 kg; adult) femur (86.5 mm), incomplete tibiotarsus (~105 mm), incomplete fibula, metatarsal I (4 mm), proximal phalanx I-1, tarsometatarsus (mtII 94 mm, mt III 107 mm, mtIV 105 mm), phalanx II-1 (10.5 mm), phalanx II-2 (8.4 mm), proximal pedal ungual II, phalanx III-1 (14.5 mm), phalanx III-2 (12 mm), proximal phalanx III-3, phalanx IV-1 (11 mm), phalanx IV-2 (10.5 mm), phalanx IV-3 (9 mm), phalanx IV-4 (9 mm), pedal ungual IV (8 mm), metatarsal V (21.5 mm)
Comments- Currie and Peng (1994) described a hindlimb as a possible juvenile Saurornithoides mongoliensis, but Norell et al. (2009) believed this specimen to be merely Troodontidae indet., as they stated hindlimb elements were undiagnostic in Saurornithoides and Zanabazar. Most recently, Xu et al. (2012) have reexamined the specimen and found it to be an adult of a new taxon of derived troodontid related to the contemporaneous Linhevenator.
References- Currie and Peng, 1994. A juvenile specimen of Saurornithoides mongoliensis from the Upper Cretaceous of northern China. Canadian Journal of Earth Sciences. 30(10), 2224-2230.
Currie and Dong, 2001. New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People's Republic of China. Canadian Journal of Earth Sciences. 38, 1753-1766.
Norell and Hwang, 2004. A troodontid dinosaur from Ukhaa Tolgod (Late Cretaceous Mongolia). American Museum Novitates. 3446, 9 pp.
Norell, Makovicky, Bever, Balanoff, Clark, Barsbold and Rowe, 2009. A review of the Mongolian Cretaceous dinosaur Saurornithoides (Troodontidae: Theropoda). American Museum Novitates. 3654, 63 pp.
Xu, Zhao, Sullivan, Tan, Sander and Ma, 2012. The taxonomy of the troodontid IVPP V 10597 reconsidered. Vertebrata PalAsiatica. 50(2), 140-150.

Urbacodon Averianov and Sues, 2007
U. itemirensis Averianov and Sues, 2007
Cenomanian, Late Cretaceous
Dzharakuduk Formation, Uzbekistan
Holotype
- (ZIN PH 944/16) dentary, six teeth
Reference- Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.
U? sp. (Averianov and Sues, 2007)
Late Turonian, Late Cretaceous
Bissekty Formation, Uzbekistan
Material
- (CCMGE 2/11822) tooth (Nessov, 1995)
(CCMGE 71/12455) premaxillary tooth (Nessov, 1993)
?(CCMGE 466/12457) partial braincase (Nessov, 1995)
?(CCMGE 475/12457) mid caudal vertebra (Nessov, 1995)
?(SPbGU VZ Din 7/2) incomplete posterior dorsal vertebra (23.4 mm) (Averianov and Sues, 2016)
?(USNM 538124) distal caudal vertebra (29 mm) (Averianov and Sues, 2016)
?(ZIN PH 99/16) pedal phalanx II-2 (Averianov and Sues, 2016)
(ZIN PH 265/16) anterior dentary tooth (Averianov and Sues, 2007)
?(ZIN PH 893/16) incomplete posterior dorsal vertebra (26.6 mm) (Averianov and Sues, 2016)
(ZIN PH 1899/16) posterior maxillary or dentary tooth (Averianov and Sues, 2007)
?(ZIN PH 2308/16) partial maxilla (Averianov and Sues, 2016)
?(ZIN PH 2339/16) incomplete anterior dorsal vertebra (27.7 mm) (Averianov and Sues, 2016)?
?(ZIN PH 2340/16) incomplete distal caudal vertebra (38 mm) (Averianov and Sues, 2016)
?(ZIN PH 2341/16) distal metatarsal III (Averianov and Sues, 2016)
?(ZIN PH 2342/16) distal metatarsal III (Averianov and Sues, 2016)
?(ZIN PH 2343/16) manual phalanx I-1 (43 mm) (Averianov and Sues, 2016)
?(ZIN PO 4608) partial dentary (Nessov, 1992)
? cervical vertebrae, metacarpal I (Averianov and Sues, 2007)
Comments- Nessov (1992, 1997) identified ZIN PO 4608 as an ichthyornithine. Nessov (1993, 1997) identified CCMGE 71/12455 as Deinonychosauria or Mammalia. Nessov (1995) identified CCMGE 2/11822 as Theropoda indet., CCMGE 466/12457 as possibly dromaeosaurid, and CCMGE 475/12457 as possibly ornithomimid. Averianov and Sues (2007) reidentified these and additional specimens as being troodontid, assigned to Urbacodon sp. due to the resemblence of the dental and dentary remains to the U. itemirensis holotype. The material was described in depth by Averianov and Sues (2016), except for the braincase CCMGE 466/12457 which will be described in a future publication on troodontid endocrania. Using a reweighted version of the TWG analysis, the authors recovered Urbacodon as sister to Gobivenator outside Troodontinae.
References- Nessov, 1981. Cretaceous salamanders and frogs of the Kyzylkum Desert. Trudy Zoologicheskogo Instituta AN SSSR. 101, 57-88.
Nessov, 1992. Review of localities and remains of Mesozoic and Paleogene birds of the USSR and the description of new finds. Russkii Ornitologicheskii Zhurnal. 1, 7-50.
Nessov, 1993. New Mesozoic mammals of Middle Asia and Kazakhstan and comments about evolution of theriofaunas of the Cretaceous coastal plains of Asia. Trudy Zoologicheskogo Instituta RAN. 249, 105-133.
Nessov, 1995. Dinosaurs of northern Eurasia: New data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg. 1-156.
Nessov, 1997. Cretaceous nonmarine vertebrates of Northern Eurasia. Izdatelstvo Sankt-Peterburgskogo Universiteta, Saint Petersburg. 218 pp.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.
Averianov and Sues, 2016. Troodontidae (Dinosauria: Theropoda) from the Upper Cretaceous of Uzbekistan. Cretaceous Research. 59, 98-110.

Troodontinae Gilmore, 1924 vide Martyniuk, 2012
Definition- (Troodon formosus + Saurornithoides mongoliensis) (Martyniuk, 2012)
= Saurornithoidinae Barsbold, 1974 vide Martyniuk, 2012
Diagnosis- enlarged serrations; mesial carinae of some lateral teeth serrated; distal articular surface of metatarsal III extends far proximally.
Reference- Martyniuk, 2012. A Field Guide to Mesozoic Birds and Other Winged Dinosaurs. Vernon, New Jersey. Pan Aves. 189 pp.

"Saurornitholestes" robustus Sullivan, 2006
Late Campanian, Late Cretaceous
De-na-zin Member of the Kirtland Formation, New Mexico, US

Holotype- (SMP VP-1955) frontal (62 mm) (Sullivan, 2006)
Referred- ?(NMMNH P-68396) tooth (4.8x5.5x2.9 mm) (Williamson and Brusatte, 2014)
Diagnosis- Provisionally indeterminate relative to Troodon formosus, and incomparable to Talos.
Other diagnoses- Sullivan (2006) used the ratio of length (measured along the midline) to thickness (posterior part of the frontal) being 6:1 to distinguish robustus from S. langstoni, but this matches the condition in Troodon formosus once wear in robustus is accounted for.
Comments- Sullivan (2006) originally described the frontal as a new species of the dromaeosaurid Saurornitholestes, distinguished from S. langstoni by its greater thickness. Turner et al. (2012) stated the holotype lacks the synapomorphies of Saurornitholestes, but listed no characters of that genus. They instead placed it as Theropoda indet.. Evans et al. (2014) reexamined the specimen and determined it was nearly identical to Troodon and indeterminate among derived troodontids. The tooth was said to fall within the range of variation of Dinosaur Park Troodon teeth by Williamson and Brusatte (2014).
References- Williamson, 2001. Dinosaurs from microvertebrate sites in the Upper Cretaceous Fruitland and Kirtland Formations, San Juan Basin, New Mexico. 2001 GSA abstracts.
Sullivan, 2006. Saurornitholestes robustus, n. sp. (Theropoda: Dromaeosauridae) from the Upper Cretaceous Kirtland Formation (De-na-zin Member), San Juan Basin, New Mexico. In Lucas and Sullivan (eds.). Late Cretaceous vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin. 35, 253-256.
Turner, Makovicky and Norell, 2012. A review of dromaeosaurid systematics and paravian phylogeny. Bulletin of the American Museum of Natural History. 371, 1-206.
Evans, Larson, Cullen and Sullivan, 2014. 'Saurornitholestes' robustus is a troodontid (Dinosauria: Theropoda). Canadian Journal of Earth Sciences. 51(7), 730-734.
Larson, Cullen, Todd and Evans, 2014. Geometric morphometrics of small theropod frontals from the Dinosaur Park Formation, Alberta. Journal of Vertebrate Paleontology. Program and Abstracts 2014, 165.
Williamson and Brusatte, 2014. Small theropod teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and their implications for understanding Latest Cretaceous dinosaur evolution. PLoS ONE. 9(4), e93190.

unnamed possible Troodontinae (Schwimmer, Sanders, Erickson and Weems, 2015)
Middle Campanian, Late Cretaceous
Coachman Formation, South Carolina, US
Material
- (ChM PV8689) tooth (3 mm)
(ChM PV9111) incomplete tooth
Comments- These were only assigned to Theropoda indet. by Schwimmer et al. (2015), but the large serration size, particularly on the mesial carina, suggests they belong to troodontines.
Reference- Schwimmer, Sanders, Erickson and Weems, 2015. A Late Cretaceous dinosaur and reptile assemblage from South Carolina, USA. Transactions of the American Philosophical Society. 105(2), 157 pp.

unnamed troodontine (Nessov and Golovneva, 1990)
Middle Maastrichtian, Late Cretaceous
Kakanaut Formation, Russia
Material
- (ZIN PH 1/28) partial tooth
Diagnosis- (after Averianov and Sues, 2007) no distinct pits between the bases of the distal serrations; larger serrations (1.64/mm) than T. formosus.
Comments- This was referred to cf. Troodon sp. by Nessov and Goloneva (1990) and Nessov (1995), and Troodon cf. formosus by Averianov and Sues (2007) because Troodon is known from the Maastrichtian of Alaska, but the mesial carina is missing so it is unknown if serrations extended apically as in Troodon, or not as in Saurornithoides.
References- Nessov and Golovneva, 1990. [History of the flora, vertebrates and climate in the late Senonian of the north-eastern Koriak Uplands]; pp. 191–212 in V. A. Krasilov (ed.), [Continental Cretaceous of the USSR.] Dal’nevostochnoe Otdelenie AN SSSR, Vladivostok. [Russian]
Nesov, 1992. Maastrichtian Dinosaurs of NE Asia and Climate Changes caused by vertical oceanic circulation. International Conference on Arctic Margins, Abstracts. 43.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.

unnamed possible troodontine (Rodriguez de la Rosa, 1996)
Late Campanian, Late Cretaceous
Cerro del Pueblo Formation, Mexico
Material
- (IGM-7710) pedal phalanx II-2 (22.5 mm)
Diagnosis- shaft more elongate than other troodontids; proximoventral heel bifurcated.
Comments- Rodriguez de la Rosa and Cevallos-Ferriz (1998) refer this to the Troodontidae because the collateral ligament pit is centrally placed. This is only seen in Saurornithoides and Troodon though, not more basal forms (IGM 100/44, Sinornithoides, Borogovia). Thus IGM-7710 may be more closely related to the former two genera. Evans et al. (2014) believe this may belong to a turtle instead.
References- Hernandez, Aguillon, Delgado and Gomez, 1995. The Mexican Dinosaur National Monument. Journal of Vertebrate Paleontology. 15(3), 34A.
Rodriguez de la Rosa, 1996. Vertebrate remains from a Late Cretaceous locality (Campanian, Cerro del Pueblo Formation), Coahuila, Mexico. Journal of Vertebrate Paleontology. 16(3), 60A.
Rodriguez de la Rosa and Cevallos-Ferriz, 1998. Vertebrates of the El Pelillal locality (Campanian, Cerro del Pueblo Formation), Southeastern Coahuila, Mexico. Journal of Vertebrate Paleontology. 18, 751-764.
Evans, Larson, Cullen and Sullivan, 2014. 'Saurornitholestes' robustus is a troodontid (Dinosauria: Theropoda). Canadian Journal of Earth Sciences. 51(7), 730-734.

unnamed troodontine (Zinke, 1998)
Early Kimmeridgian, Late Jurassic
Alcobaca Formation, Portugal
Material
- (IPFUB GUI D 93-97, 100, 102, 104, 111, 114-116, 156, 190) 14 teeth (~1.02 mm; FABL ~.92 mm)
Comments- These teeth can be identified as troodontid based on their constricted roots, enlarged serrations and hooked distal serrations. The latter are particularily derived characters among troodontids, as is the presence of serrations on most mesial teeth.
Reference- Zinke, 1998, Small theropod teeth from the Upper Jurassic coal mine of Guimarota (Portugal). Palaontologische Zeischrift. 72(1/2), 179-189.

unnamed troodontine (Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002)
Late Maastrichtian, Late Cretaceous
Sinpetru Beds, Romania
Material
- teeth
Comments- These teeth are short and not recurved, with mesial and distal serration. The distal serrations are tall, enlarged (~5.5/mm) and apically hooked. They may belong to Elopteryx.
Reference- Codrea, Smith, Dica, Folie, Garcia, Godefroit and Van Itterbeecke, 2002. Dinosaur egg nests, mammals and other vertebrates from a new Maastrichtian site of the Hateg Basin (Romania). C. R. Palevol. V. 1, p. 173-180.

unnamed Troodontinae (Averianov and Sues, 2007)
Early Santonian, Late Cretaceous
Yalovach Formation, Tajikistan
Material
- (ZIN PH 1/66) anterior dentary tooth
(ZIN PH 2/66) dentary fragment
(ZIN PH 3/66) anterior dentary tooth
(ZIN PH 4/66) anterior maxillary tooth
(ZIN PH 5/66) posterior maxillary tooth
(ZIN PH 7/66) posterior dentary tooth
(ZIN PH 8/66) premaxillary tooth
?(ZIN PH 13/60) tooth
(ZIN PH coll.) at least four teeth
Comments- ZIN PH 13/60 may belong to another taxon because it is unserrated. The dentary fragment ZIN PH 2/66 lacks tooth crowns, so may be referrable to the taxon with serrated teeth or the same one as ZIN PH 13/60.
Reference- Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.

unnamed Troodontinae (Averianov and Sues, 2007)
Early Campanian, Late Cretaceous
Darbasa Formation, Kazakhstan
Material
- (ZIN PH 2/67) maxillary tooth
(ZIN PH 3/67) posterior dentary tooth
(ZIN PH 4/67) posterior dentary tooth
(ZIN PH coll.) four teeth
Comments- These teeth were identified as cf. Troodon sp. by Averianov and Nessov (1995) and Nessov (1995). They have 1.82-3.33 serrations per mm on the distal carina, while all but one lack mesial serrations. The mesial serrations on that specimen are smaller than its distal ones (3.33/mm vs. 2.33).
Reference- Averianov and Nessov, 1995. A new Cretaceous mammal from the Campanian of Kazakhstan. Neues Jahrbuch für Geologie und Paläontologie, Monatshefte. 1995, 65-74.
Nessov, 1995. Dinosaurs of nothern Eurasia: new data about assemblages, ecology, and paleobiogeography. Institute for Scientific Research on the Earth's Crust, St. Petersburg State University, St. Petersburg 1-156.
Averianov and Sues, 2007. A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union. Journal of Vertebrate Paleontology. 27(1), 87-98.

Troodontinae indet. (Currie and Eberth, 1993)
Early Maastrichtian, Late Cretaceous
Iren Dabasu Formation, Inner Mongolia, China

Material- (AMNH 6570) (subadult) axis, third cervical vertebra (Makovicky, 1995)
(AMNH 21751) distal metatarsal III, distal metatarsal II (Currie and Eberth, 1993)
(AMNH 21772) metatarsal III (Currie and Eberth, 1993)
(AMNH 25570) three vertebrae (AMNH online)
(IVPP 230790-16) metatarsal III (Currie and Eberth, 1993)
Description- AMNH 21751 and 21772 were discovered in the 1920's, provisionally referred to Saurornithoides by Currie and Eberth (1993), then described by Currie and Dong (2001), who identified them as indeterminate troodontids more derived than Sinornithoides. This was based on the proximal extent of the distal articular surface on metatarsal III. IVPP 230790-16 was discovered in 1990, provisionally referred to Saurornithoides (mistakenly as IVPP 230090-16) by Currie and Eberth (1993) , then described by Currie and Dong (2001) who came to the same conclusions as they did for AMNH 21751 and 21772. AMNH 6570 was described by Makovicky (1995). Currie and Eberth also provisionally referred a femur (PIN 2549-100) to Saurornithoides, which Osmolska (1996) thought was similar to Bagaraatan. Averianov and Sues (2012) stated it could not be assigned to Saurornithoides though was probably troodontid, which may agree with the similarity to Bagaraatan if the latter's hindlimb is referrable to the family.
Comments- Provisionally referred to Saurornithoides by Currie and Eberth (1993), but said to be an undetermined derived troodontid by Currie and Dong (2001). AMNH 21751 consists of two elements the right size to belong to the same individual, but are different colors, so may not.
References- Currie and Eberth, 1993. Palaeontology, sedimentology and palaeoecology of the Iren Dabasu Formation (Upper Cretaceous), Inner Mongolia, People’s Republic of China. Cretaceous Research. 14 127-144.
Makovicky, 1995. Phylogenetic aspects of the vertebral morphology of Coelurosauria (Dinosauria: Theropoda). M.S. thesis, Univ. Copenhagen, 311pp.
Osmolska, 1996. An unusual theropod dinosaur from the Late Cretaceous Nemegt Formation of Mongolia. Acta Palaeontologica Polonica. 41, 1-38.
Currie and Dong, 2001. New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People's Republic of China. Canadian Journal of Earth Sciences. 38, 1753-1766.
Averianov and Sues, 2012. Correlation of Late Cretaceous continental vertebrate assemblages in middle and central Asia. Journal of Stratigraphy. 36(2), 462-485.

undescribed troodontid (Codrea, Godefroit and Smith, 2012)
Maastrichtian, Late Cretaceous
Rusca Montana Basin, Romania
Material
- (UBB NgTh1) tooth
Reference- Codrea, Godefroit and Smith, 2012. First discovery of Maastrichtian (Latest Cretaceous) terrestrial vertebrates in Rusca Montana Basin (Romania). In Godefroit (ed.). Bernissart Dinosaurs and Early Cretaceous Terrestrial Ecosystems. Indiana University Press. 570-581.

unnamed troodontid (Goswami, Prasad, Benson, Verma and Flynn, 2012)
Late Maastrichtian, Late Cretaceous
Kallamedu Formation, India
Material
- (DUGF/52) tooth (3.5 x 2.8 mm)
References- Goswami, Prasad, Benson, Verma and Flynn, 2012. New vertebrates from the Late Cretaceous Kallamedu Formation, Cauvery Basin, South India, including a troodontid dinosaur, a gondwanatherian mammal, and a Simosuchus-like notosuchian crocodyliform. Journal of Vertebrate Paleontology. Program and Abstracts 2012, 102.
Goswami, Prasad, Verma, Flynn and Benson, 2013. A troodontid dinosaur from the latest Cretaceous of India. Nature Communications. 4, 1703.

Borogovia Osmolska, 1987
B. gracilicrus Osmolska, 1987
Early Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia
Holotype
- (ZPAL MgD-I/174) incomplete tibiotarsi (280+ mm, 27 mm wide), proximal fibula, distal metatarsal II, phalanx II-1 (32 mm), phalanx II-2 (13 mm), pedal ungual II (31 mm), distal metatarsal III, distal phalanx III-1, phalanx III-2 (23 mm), phalanx III-3 (22 mm), pedal ungual III (15 mm), distal metatarsal IV, phalanx IV-1 (18 mm), phalanx IV-2 (17 mm), phalanx IV-3 (15 mm), phalanx IV-4 (16 mm), pedal ungual IV (21.5 mm)
Comments- This specimen was first mentioned by Osmolska (1982) as Saurornithoides sp. and may be a junior synonym of Zanabazar, as posited by Osmolska (1987). The currently known specimens of each taxon do not overlap.
References- Osmolska, 1982. Hulsanpes perlei n.g.n.sp. (Deinonychosauria, Saurisichia, Dinosauria) from the Upper Cretaceous Barun Goyot Formation of Mongolia. Neües Jahrbuch fur Geologie und Palaontologie Monatschefte. 1982(7), 440-448.
Osmolska, 1987. Borogovia gracilicrus gen. et sp. n., a new troodontid dinosaur from the Late Cretaceous of Mongolia. Acta Palaeontologica Polonica. 32, 133-150.

Saurornithoides Osborn, 1924
= "Ornithoides" Osborn, 1924
S. mongoliensis Osborn, 1924
= "Ornithoides oshiensis" Osborn, 1924
= Troodon mongoliensis (Osborn, 1924) Paul, 1988
Late Campanian, Late Cretaceous
Djadokhta Formation, Mongolia

Holotype- (AMNH 6516) (1.56 m; 13 kg) incomplete skull (192 mm), three sclerotic plates, incomplete mandibles, ninth dorsal vertebra, tenth dorsal vertebra (23 mm), eleventh dorsal vertebra (22 mm), incomplete twelfth dorsal vertebra (23 mm), (sacrum 147 mm) incomplete first sacral vertebra (23 mm), partial second sacral centrum (24 mm), partial third sacral centrum (25 mm), partial fourth sacral centrum (25 mm), partial fifth sacral vertebra (25 mm), incomplete sixth sacral vertebra (25 mm), incomplete first caudal vertebra (22 mm), incomplete second caudal vertebra (23 mm), partial third caudal vertebra, partial fourth caudal vertebra, incomplete first chevron, partial second chevron, partial third chevron, ilial fragment, incomplete pubes, ischia (114 mm), proximal femur (~198 mm), tibial mold (~243 mm), metatarsal I fragments, phalanx I-1 (16 mm), incomplete pedal ungual I, partial metatarsal II, phalanx II-1 (27.5 mm), phalanx II-2 (14 mm), pedal ungual II (29.3 mm), distal metatarsal III (~139 mm), phalanx III-1 (~33 mm), phalanx III-2 (24 mm), proximal phalanx III-3, partial metatarsal IV, phalanx IV-1 (20.5 mm), proximal phalanx IV-2
Referred- ?(IGM 100/1083) (1.85 m; 21 kg) maxillary fragment, incomplete quadrate, incomplete anterior cervical vertebra, partial anterior dorsal vertebra, sacral fragment, three distal caudal vertebrae, distal tarsal IV, pedal ungual II (34.7 mm), distal metatarsal III, proximal metatarsal IV, four pedal phalanges (Norell and Hwang, 2004)
Late Campanian, Late Cretaceous
Djadokhta equivalent, Inner Mongolia, China
?(IVPP V10599) partial sacrum, caudal vertebrae, chevrons, pelvis (Currie and Dong, 2001)
Diagnosis- More derived than Sinornithoides and Sinusonasus due to the absent promaxillary fenestra, large serrations on teeth, and six sacral vertebrae. Less derived than Zanabazar and Troodon due to the dorsal tympanic recess.
Other diagnoses- Osborn (1924) was the first to publish a diagnosis, but as the specimen was the first troodontid known from more than teeth, the generic diagnosis is now far too generalized. The presence of five pairs of external cranial fenestrae is incorrect, as Osborn did not take the supratemporal fenestrae into account, but six pairs are primitive for tetanurines anyway. The external mandibular fenestra is primitive for archosaurs, while the fairly homodont maxillary series is primitive for an even more inclusive group. The presence of nineteen premaxillary and maxillary teeth is incorrect, as there are actually twenty-three. The "less raptorial" teeth are also found in other maniraptoriforms except dromaeosaurids. Teeth which have only distal serrations are also now known in several other troodontids (e.g. Sinornithoides, Sinusonasus, Zanabazar). Maxillary teeth which lack replacement gaps are also present in Mei, Sinovenator and basal avialans, so may be plesiomorphic. Of his listed "specific characters", the posteriorly increasing size of maxillary teeth, closely spaced dentary teeth, and teeth with a sub-acute tip are common in troodontids. The premaxillary teeth do not decrease in size posteriorly though, as the first tooth is small, the second unpreserved, and the third and fourth subequal (Norell et al., 2009). The illusion of decreasing size is due to the length of the roots which are exposed. Flattened, recurved teeth are primitive for archosaurs
Norell et al. (1009) listed several characters in their diagnosis, as they differ from Zanabazar. While Saurornithoides is smaller than Zanabazar, Norell et al. note all other named troodontids except perhaps Troodon are as well. Norell et al. also distinguish it from Zanabazar by its low tooth count (19 maxillary teeth and ~31-33 dentary teeth), but Sinornithoides (18 maxillary teeth), Sinusonasus (~19 maxillary teeth) and Urbacodon (32 dentary teeth) are similar. A jugal with a straight ventral edge below the front of the orbit is also present in Mei and seemingly Sinornithoides, and is somewhat uncertain in Saurornithoides due to breakage in any case. The dorsal tympanic recess is plesiomorphic, being present in Byronosaurus and Sinovenator as well. Norell et al. note their last listed character (maxillary teeth with only slight posterior increase in height) is also present in Mei, Sinovenator and basal avialans, so may be plesiomorphic.
Comments- A partial sacrum, three mid caudal vertebrae and two partial ilia were originally included in the holotype, but were reidentified as protoceratopsian by Norell et al. (2009) and placed in the new number AMNH 30613. Currie and Peng (1994) described a hindlimb as a possible juvenile Saurornithoides mongoliensis, but Norell et al. believed this specimen to be merely Troodontidae indet., as they stated hindlimb elements were undiagnostic in Saurornithoides and Zanabazar. Yet the extremely slender elements are similar to a basal undescribed troodontid from the same stratigraphic level, while the short flexor lip on metatarsal III is more primitive than Saurornithoides. It is tentatively referred to that unnamed species here. Norell and Hwang (2004) described a fragmentary specimen they provisionally referred to Saurornithoides mongoliensis, as it was identical except for being larger. Norell et al. noted definitive referral was not possible, though they did state the tooth replacement was more similar to Saurornithoides than to Byronosaurus, the only other named troodontid from that formation. IVPP V10599 was mentioned by Currie and Dong as being referrable to Saurornithoides mongoliensis and having a sixth sacral vertebra derived from the caudal series, but details including a rationale for the referral are lacking.
References- Osborn, 1924. The discovery of an unknown continent. Natural History. XXIV, 133-149.
Osborn, 1924. Three new Theropoda, Protoceratops zone, central Mongolia. American Museum Novitates. 144, 1-12.
Russell, 1969. A new specimen of Stenonychosaurus from the Oldman Foramtion of Alberta. Canadian Journal of Earth Sciences. 6, 595-612.
Barsbold, 1974. Saurornithoididae, a new family of small theropod dinosaurs from Central Asia and North America. Palaeontologia Polonica. 30, 5-22.
Paul, 1988. Predatory Dinosaurs of the World. Simon and Schuster Co., New York. 464 pp.
Osmolska and Barsbold, 1990. Troodontidae. In Weishampel, Dodson, and Osmolska (eds). The Dinosauria, Berkeley: University of California Press. 259-268.
Currie and Peng, 1994. A juvenile specimen of Saurornithoides mongoliensis from the Upper Cretaceous of northern China. Canadian Journal of Earth Sciences. 30(10), 2224-2230.
Currie and Dong, 2001. New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People's Republic of China. Canadian Journal of Earth Sciences. 38, 1753-1766.
Norell and Hwang, 2004. A troodontid dinosaur from Ukhaa Tolgod (Late Cretaceous Mongolia). American Museum Novitates. 3446, 9 pp.
Norell, Makovicky, Bever, Balanoff, Clark, Barsbold and Rowe, 2009. A review of the Mongolian Cretaceous dinosaur Saurornithoides (Troodontidae: Theropoda). American Museum Novitates. 3654, 63 pp.

Zanabazar Norell, Makovicky, Bever, Balanoff, Clark, Barsbold and Rowe, 2009
= "Mongolodon" Franzosa, 2004
Z. junior (Barsbold, 1974) Norell, Makovicky, Bever, Balanoff, Clark, Barsbold and Rowe, 2009
= Saurornithoides junior Barsbold, 1974
= "Mongolodon" junior (Barsbold, 1974) Franzosa, 2004
Early Maastrichtian, Late Cretaceous
Nemegt Formation, Mongolia

Holotype- (IGM 100/1) (2.28 m, 27 kg, adult) skull (280.6 mm), anterior mandibles, (sacrum- 200 mm) first sacral vertebra (~34 mm), second sacral vertebra (~31 mm), third sacral vertebra (31 mm), fourth sacral vertebra (31 mm), fifth sacral vertebra (36 mm), sixth sacral vertebra (36.2 mm), proximal caudal vertebra (~31.5 mm), proximal caudal vertebra (33 mm), proximal caudal vertebra (32 mm), proximal caudal vertebra (32 mm), proximal caudal vertebra (33 mm), proximal caudal vertebra (32.8 mm), mid caudal vertebra (31.5 mm), mid caudal vertebra (34 mm), mid caudal vertebra (37 mm), distal caudal vertebra (38 mm), distal caudal vertebra (38 mm), distal caudal vertebra (39 mm), distal caudal vertebra (39.5 mm), distal caudal vertebra (39.5 mm), two proximal chevrons, mid chevron, five distal chevrons, distal tibia (68 mm wide), astragalocalcaneum, distal tarsal III, distal tarsal IV, proximal metatarsal II, proximal metatarsal III, proximal metatarsal IV
Referred- ?(IGM 100/2) postcrania
Diagnosis- (after Norell et al., 2009) exoccipital forms large part of posttemporal fenestra (unknown in other troodontids except Troodon); deep paroccipital processes, with proximodorsal edge above foramen magnum.
Other diagnoses- Barsbold (1974) originally listed a few characters in his diagnosis. The large size is also seen in Troodon. The maxillary tooth count (19-20) overlaps Saurornithoides (19) and Sinusonasus (~19), while the dentary tooth count (35) is the same as Troodon.
Norell et al. also listed several other characters in their diagnosis. The absent dorsal tympanic recess is shared with Troodon. They note the foramen magnum is more transversely compressed than Troodon, but that Byronosaurus and Sinovenator are similar, making it plesiomorphic. Similarly, the lack of a separate canal for the opthalmic branch of the trigeminal nerve is also seen in Byronosaurus and most dromaeosaurids, meaning it is plesiomorphic as well.
Comments- Contrary to Barsbold (1974), Norell et al. note the teeth lack mesial serrations, the caudal vertebrae are probably not a continuous series, and the distal fibula is unpreserved. However, they also fail to note three proximal caudal vertebrae in their materials list and description. Franzosa (2004) assigns this species to a new genus "Mongolodon" without comment in his unpublished thesis. However, Norell et al. (2009) later redescribed the species and made it the type of their new genus Zanabazar. This was largely done because of the absence of characters supporting a sister relationship with Saurornithoides mongoliensis, though Norell et al. do not explicitly support a closer relationship of either species to Troodon either. Borogovia may be a junior synonym (Osmolska, 1987), as its holotype cannot be compared to IGM 100/1. Tochisaurus is not a junior synonym however (Kurzanov and Osmolska, 1991), though this was proposed as possible by Osmolska.
References- Barsbold, 1974. Saurornithoididae, a new family of small theropod dinosaurs from Central Asia and North America. Palaeontologia Polonica. 30, 5-22.
Osmolska, 1987. Borogovia gracilicrus gen. et sp. n., a new troodontid dinosaur from the Late Cretaceous of Mongolia. Acta Palaeontologica Polonica. 32, 133-150.
Osmolska and Barsbold, 1990. Troodontidae. In Weishampel, Dodson, and Osmolska, eds.. The Dinosauria, Berkeley: University of California Press: 259-268.
Kurzanov and Osmólska, 1991. Tochisaurus nemegtensis gen. et sp. n., a new troodontid (Dinosauria, Theropoda) from Mongolia. Acta Palaeontologia Polonica. 36, 69-76.
Russell and Dong, 1994. A nearly complete skeleton of a new troodont dinosaur from the Early Cretaceous of the Ordos Basin, Inner Mongolia, People's Republic of China. Canadian Journal of Earth Sciences. 30(10), 2163-2173.
Franzosa, 2004. Evolution of the Brain in Theropoda (Dinosauria). PhD Thesis. The University of Texas at Austin. 357 pp.
Norell, Makovicky, Bever, Balanoff, Clark, Barsbold and Rowe, 2009. A review of the Mongolian Cretaceous dinosaur Saurornithoides (Troodontidae: Theropoda). American Museum Novitates. 3654, 63 pp.

Troodon Leidy, 1856
= Polyodontosaurus Gilmore, 1932
= Stenonychosaurus Sternberg, 1932
= Pectinodon Carpenter, 1982
T. formosus Leidy, 1856
= Laelaps cristatus Cope, 1876
= Dryptosaurus cristatus (Cope, 1876) Hay, 1902
= Deinodon cristatus (Cope, 1876) Osborn, 1902 non (Marsh, 1892) Hay, 1902
= Dromaeosaurus cristatus (Cope, 1876) Matthew and Brown, 1922
= Polyodontosaurus grandis Gilmore, 1932
= Stenonychosaurus inequalis Sternberg, 1932
= Saurornithoides inequalis (Sternberg, 1932) Carpenter, 1982
= Stegoceras formosum (Leidy, 1856) Olshevsky, 1991
= Troodon cristatus (Cope, 1876) Olshevsky, 1995
= Troodon inequalis (Sternberg, 1932) Snively and Russell, 2002
Late Campanian, Late Cretaceous
Judith River Formation, Montana, US
Holotype
- (ANSP 9259) posterior premaxillary tooth
Referred- (AMNH 3954; syntypes of Laelaps cristatus) two maxillary teeth (11 mm)
(AMNH 8519) tooth (Sahni, 1972)
(AMNH 8520) tooth (3.4 mm) (Sahni, 1972)
(AMNH 21760) tooth (AMNH online)
(ANSP 15937) dentary tooth (Fiorillo and Currie, 1994)
(ANSP 15947) maxillary tooth (Fiorillo and Currie, 1994)
(ANSP 15950) maxillary tooth (Fiorillo and Currie, 1994)
(ANSP 15964) dentary tooth (Fiorillo and Currie, 1994)
(ANSP 17642) premaxillary tooth (Fiorillo and Currie, 1994)
(ANSP 17780) premaxillary tooth (Fiorillo and Currie, 1994)
(ANSP 17795) premaxillary tooth (Fiorillo and Currie, 1994)
(ANSP 18005) maxillary tooth (Fiorillo and Currie, 1994)
(MOR 170) vertebra (MOR online)
(MOR 320) tooth (MOR online)
(MOR 993) (embryo) tooth, centrum, limb elements, partial egg (Varricchio and Jackson, 2004)
Late Campanian, Late Cretaceous
Oldman Formation of the Judith River Group, Alberta, Canada

(RTMP 89.77.5) tooth (Ryan and Russell, 2001)
(RTMP 94.157.1) eggshells (Zelenitsky, Modesto and Currie, 2002)
(RTMP 94.157.2) eggshells (Zelenitsky, Modesto and Currie, 2002)
(RTMP 94.157.4) eggshells (Zelenitsky, Modesto and Currie, 2002)
(RTMP 94.157.5) eggshells (Zelenitsky, Modesto and Currie, 2002)
(RTMP 138.319) tooth (Ryan, 2003)
(RTMP coll.) tooth (Chiba, Ryan, Braman, Eberth, Scott, Brown, Kobayashi and Evans, 2015)
teeth (Ryan and Russell, 2001)
(embryos and adults) material (Zelenitsky, Modesto and Currie, 2002)
Late Campanian, Late Cretaceous
Dinosaur Park Formation of the Judith River Group, Alberta, Canada

(AMNH 6174) frontals, parietals, laterosphenoid (Russell, 1969)
(AMNH 21598) tooth (AMNH online)
(AMNH 21714) tooth (AMNH online)
(CMN 199) distal tibia (58.6 mm wide), astragalus (Russell, 1969)
(CMN 1267) premaxillary tooth (Lambe, 1902)
(CMN 1650) distal manual phalanx, pedal ungual I (52 mm), phalanx II-1 (47.6 mm), phalanx II-2 (24.8, 24.6 mm), pedal ungual II (~70 mm), pedal ungual IV (~45 mm) (Russell, 1969)
(CMN 2506) pedal phalanx II-1 (Russell, 1969)
(CMN 8539; holotype of Stenonychosaurus inequalis) six distal caudal vertebrae, metacarpal I (36.5 mm), distal phalanx I-1, distal metacarpal II, partial phalanx II-1, distal manual phalanx, distal tibia, astragalus, metatarsal I, phalanx I-1 (~29 mm), pedal ungual I (~45 mm), metatarsal II (202.4 mm), phalanx II-1 (~50.5 mm), phalanx II-2 (29 mm), pedal ungual II, metatarsal III (253.6 mm), phalanx III-1 (~66 mm), phalanx III-2 (41.2 mm), phalanx III-3 (39.3 mm), pedal ungual III (~55 mm), metatarsal IV (244.5 mm), phalanx IV-1 (~34.2 mm), phalanx IV-2 (~28.3 mm), phalanx IV-3 (~23.6 mm), phalanx IV-4 (~24.5 mm), pedal ungual IV (~47 mm) (Sternberg, 1932)
(CMN 8540; holotype of Polyodontosaurus grandis) dentary (117.5 mm) (Gilmore, 1932)
(CMN 12340) postorbital, frontals, parietals, basioccipital, basisphenoid, dorsal centrum fragment, four dorsal ribs, seven gastralia, three distal caudal vertebra fragments, three chevrons, proximal radius, ulnae (one distal) (131 mm), semilunate carpal, incomplete manual phalanx II-1, manual ungual, incomplete femur, astragali, metatarsal I, phalanx I-1 (26.3 mm), pedal ungual I (46.5 mm), metatarsal II fragments, phalanx II-1 (46.7 mm), pedal ungual II (65, 66 mm), metatarsal III fragments, phalanx III-1, phalanx III-3 (32.8 mm), pedal ungual III, metatarsal IV fragments, phalanx IV-1 (33.5 mm), phalanx IV-2 (27.3 mm), pedal ungual IV (~43 mm) (Russell, 1969)
(CMN 12392) anterior maxilla, fragments (Russell, 1969)
(CMN 12425) astragalus (58.4 mm wide) (Russell, 1969)
(CMN 12433) ulna (138 mm) (Russell, 1969)
(CMN 12434) pedal phalanx II-1 (Russell, 1969)
(CMN coll.) distal metacarpal I (?), astragalus, calcaneum(?), distal metatarsal I (?), pedal ungual II (Lambe, 1902)
(PMAA P67.14.39) partial dentary (Sues, 1977)
(ROM 1445) partial dentary, second dentary tooth, thirteenth dentary tooth, twentieth dentary tooth (Russell, 1948)
(RTMP 65.23.32) maxillary tooth (10 mm) (Currie, Rigby and Sloan, 1990)
(RTMP 67.14.39) partial dentary, fourteenth dentary tooth (Sues, 1977)
(RTMP 79.8.1) frontals, parietals, laterosphenoid (Currie, 1985)
(RTMP 79.8.635) (juvenile) posterior dentary tooth (4 mm) (Currie, 1987)
(RTMP 79.8.1171) tooth (Baszio, 1997)
(RTMP 80.16.1473) parietals (Currie, 1985)
(RTMP 80.16.1478) frontals, mesethmoid (Currie, 1985)
(RTMP 81.22.66) (Currie, 1985)
(RTMP 81.37.15) tenth cervical vertebra (Makovicky, 1995)
(RTMP 82.16.124) frontals, parietals (Currie, 1985)
(RTMP 82.16.138) partial dentary (Currie, 1987)
(RTMP 82.16.282) premaxillary tooth (Currie, 1987)
(RTMP 82.19.23) lacrimal, postorbitals, squamosals, frontals, parietals, braincase (Currie, 1985)
(RTMP 82.19.151) partial dentary (Currie, 1987)
(RTMP 82.20.259) premaxillary tooth (Currie, 1987)
(RTMP 83.12.11) dentary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 83.36.214) maxillary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 83.36.215) tooth (Currie, Rigby and Sloan, 1990)
(RTMP 83.45.7) maxillary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 83.45.8) tooth (Currie, Rigby and Sloan, 1990)
(RTMP 84.65.1) distal metatarsal II, incomplete metatarsal III, distal metatarsal IV (Wilson and Currie, 1985)
(RTMP 85.6.3) premaxillary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 85.6.186) maxillary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 86.36.4) frontal (Currie, 1987)
(RTMP 86.36.457) incomplete braincase (Currie and Zhao, 1993)
(RTMP 86.49.10) frontal (Currie, 1987)
(RTMP 86.54.66) premaxillary tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 86.177.8) maxillary tooth (Sankey, Brinkman, Guenther and Currie, 2002)
(RTMP 88.50.58) tooth (Baszio, 1997)
(RTMP 88.96.2) maxillary tooth (Currie, Rigby and Sloan, 1990)
(RTMP 89.36.268) tooth (Ryan and Russell, 2001)
(RTMP 89.76.50) tooth (Baszio, 1997)
(RTMP 89.77.5) tooth (Baszio, 1997)
(RTMP 89.89.4) tooth (Baszio, 1997)
(RTMP 89.116.63) tooth (Baszio, 1997)
(RTMP 90.34.1) tooth (Baszio, 1997)
(RTMP 92.36.575) dentary, metatarsal II, metatarsal III, metatarsal IV (Rauhut, 2003)
(RTMP 92.36.1212) (adult) posterior cervical vertebra (Makovicky, 1995)
(RTMP 94.12.438) third dorsal vertebra (Makovicky, 1995)
(UA 5282) frontal (Russell, 1969)
(UA 5284) distal metatarsal III (Russell, 1969)
(YPM PU 23414) parietals (Currie, 1985)
teeth (Brinkman, 1990)
Campanian, Late Cretaceous
Two Medicine Formation, Montana, US

(MOR 246) nest (Horner and Weishampel, 1988)
....(MOR 246-1) (embryo) teeth, two cervical centra (4.4 mm), cervical neural arch, sacral centrum (5.1 mm), scapula (14.7 mm), fragmentary coracoid, humerus (20.3 mm), partial tibiae, partial fibula, egg
....(MOR 246-2) (embryo) humerus, egg
....(MOR 246-3) egg
....(MOR 246-5) (embryo) bone, egg
....(MOR 246-7) (embryo) bone, egg
....(MOR 246-8) (embryo) femur, egg
....(MOR 246-9) (embryo) bone, egg
....(MOR 246-10) (embryo) bone, egg
....(MOR 246-11) (embryo) (skull ~50 mm) maxilla (~18 mm), quadrate (12.1 mm), basioccipital, teeth (1 mm), vertebrae, ilia, pubes (~23 mm), ischial fragments, femur (34.9 mm), tibiae (46 mm), partial fibula, metatarsal II, metatarsal III, metatarsal IV (33.5 mm)
....(MOR 246-12) egg
....(MOR 246-13) (embryo) bone, egg
....(MOR 246-14) egg
....(MOR 246-15) egg
....(MOR 246-16) (embryo) bone, egg
....(MOR 246-17) (embryo) bone, egg
....(MOR 246-18 (embryo) bone, egg
(MOR 247) egg (Varricchio, Horner and Jackson, 2002)
(MOR 299) eggs (Varricchio, Horner and Jackson, 2002)
(MOR 323) tooth (MOR online)
(MOR 363-7-4-83-1) nest, twenty-two eggs (Varricchio, Jackson, Borkowski and Horner, 1997)
(MOR 393) nest, twenty-two eggs (Varricchio, Horner and Jackson, 2002)
(MOR 430) (several month old juvenile) partial skeleton including premaxilla, caudal vertebrae, femur (126 mm), tibia (173 mm), metatarsal IV (105 mm) (Currie, Rigby and Sloan, 1990)
(MOR 493) metatarsals, pedal phalanges (MOR online)
(MOR 510) tooth (MOR online)
(MOR 511) teeth (MOR online)
(MOR 512) teeth (MOR online)
(MOR 513) teeth (MOR online)
(MOR 553) anterior dorsal vertebra, distal caudal vertebrae (Makovicky, 1995)
(MOR 553-1) metatarsal II, metatarsal III, metatarsal IV (Varricchio, 1993)
(MOR 553-2) metatarsal (Varricchio, 1997)
(MOR 553-6.21.9) fourth cervical vertebra (Makovicky, 1995)
(MOR 553-7.7.91.19) tibia (Zanno et al., 2011)
(MOR 553-7.16.0.61) femur (Varricchio, 1993)
(MOR 553-7.21.92.46) (adult) ninth or tenth cervical vertebra (Makovicky, 1995)
(MOR 553-7.24.8.64) tibia (425 mm) (Varricchio, 1993)
(MOR 553-7.28.91.236) tenth cervical vertebra (Makovicky, 1995)
(MOR 553-7.20.91.120) anterior dorsal vertebra (Makovicky, 1995)
(MOR 553-7.23.91.36) first caudal vertebra (Makovicky, 1995)
(MOR 553-8.3.92.141) (adult) eighth cervical vertebra (Makovicky, 1995)
(MOR 553-8.8.92.186) first dorsal vertebra (Makovicky, 1995)
(MOR 553-8.10.92.203) (adult) twelfth dorsal vertebra (Makovicky, 1995)
(MOR 553-8.11.92.204) third cervical vertebra (Makovicky, 1995)
(MOR 553-8.12.92.222) (juvenile) eighth or ninth cervical vertebra (Makovicky, 1995)
(MOR 553-8.19.92.212) fourth cervical vertebra (Makovicky, 1995)
(MOR 553-8.20.92.305) (adult) sixth or seventh dorsal vertebra (Makovicky, 1995)
(MOR 553D) partial sacrum (Makovicky, 1995)
(MOR 553L-7.25.89.313) pedal ungual II (Wolff, Varricchio and Hanna, 2015)
(MOR 553L-7.27.8.87) ischium (Hutchinson, 2001)
(MOR 553S) material including more precise specimens below and the following which may be those specimens- four humeri (129.4, 143.4, 146.7, 178.7 mm), pubis, ischium, five femora (218, 233, 238, 273, 302 mm), six tibiae (283, 317, 323, 361, 382, 431 mm) and three metatarsals III (114.3, 124.2, 130.7 mm) (Carrano, 1998)
(MOR 553S-7.1.9.9) metatarsal IV (Zanno et al., 2011)
(MOR 553S-7.8.91.28) metatarsal II (Zanno et al., 2011)
(MOR 553S-7.16.0.61) (adult) femur (Zanno et al., 2011)
(MOR 553S-7.18.92.5) metatarsal II (Zanno et al., 2011)
(MOR 553S-7.20.91.120) dorsal vertebra (Wolff, Varricchio and Hanna, 2015)
(MOR 553S-7.21.92.47) maxilla (MOR online)
(MOR 553S-7.28.8.102) metatarsal IV (Zanno et al., 2011)
(MOR 553S-7.28.91.236) cervical vertebra (Wolff, Varricchio and Hanna, 2015)
(MOR 553S-7.28.91.239) (adult) femur (Zanno et al., 2011)
(MOR 553S-7.29.92.113) metatarsal III (Zanno et al., 2011)
(MOR 553S-8.2.91.303) humerus (MOR online)
(MOR 553S-8.2.92.131) braincase (MOR online)
(MOR 553S-8.3.9.387) pubis (Zanno et al., 2011)
(MOR 553S-8.3.92.141) cervical vertebra (Wolff, Varricchio and Hanna, 2015)
(MOR 553S-8.12.92.219) ulna (Zanno et al., 2011)
(MOR 553S-8.13.92.237) metacarpal II (Wolff, Varricchio and Hanna, 2015)
(MOR 553S-8.17.92.260) metatarsal IV (Wolff, Varricchio and Hanna, 2015)
(MOR 553S-8.17.92.265) fibula (Zanno et al., 2011)
(MOR 553S-8.20.92.305) mid dorsal vertebra (Zanno et al., 2011)
(MOR 553S-8.20.92.311) astragalus (Zanno et al., 2011)
(MOR 553S-8.28.92.270) mid dorsal vertebra (Zanno et al., 2011)
(MOR 553S-8.69.406) metatarsal III (Zanno et al., 2011)
(MOR 553S-11.1.01.1) astragalus (Zanno et al., 2011)
(MOR 553S-11.1.01.8; = MOR 553S 1.11.01.8 of Wolff, Varricchio and Hanna, 2015?) metatarsal IV (Zanno et al., 2011)
(MOR 553S-92.260) metatarsal IV (Zanno et al., 2011)
(MOR 558) braincase, three cervical vertebrae, elements (MOR online)
(MOR 563) (year old juvenile) skeleton including tibia, metatarsal III (Varricchio, 1993)
?(MOR 564) (embryo) maxilla (MOR online)
?(MOR 584) partial skeleton (MOR online)
(MOR 615) eggs (MOR online)
(MOR 646) jaw fragment (MOR online)
(MOR 675) eggs (Varricchio, Horner and Jackson, 2002)
(MOR 676) two nests including eleven and eight eggs (Varricchio, Horner and Jackson, 2002)
(MOR 702) two eggs (Varricchio and Jackson, 2004)
(MOR 721) specimen including femur (156.9 mm) and tibia (224 mm) (Carrano, 1998)
(MOR 748) (12 year old adult) nine proximal caudal vertebrae, eight distal caudal vertebrae, partial pelvis, femur (320 mm), tibia (362 mm), fibula, astragalus, metatarsal I, metatarsal II, metatarsal III (206.5 mm), metatarsal IV (227 mm), four pedal phalanges, nest, at least ten eggs (Varricchio, Jackson, Borkowski and Horner, 1997)
(MOR 750) eggs (Varricchio, Horner and Jackson, 2002)
(MOR 796) five vertebrae, partial ribs (MOR online)
(MOR 963) nest, twenty-four eggs (Varricchio, Jackson, Borkowski and Horner, 1997)
(MOR 964) eggs (MOR online)
(MOR 1006) partial egg (MOR online)
(MOR 1115) twenty-four eggs (MOR online)
(MOR 1138) eggs (MOR online)
(MOR 1139) eggs (Varricchio, Horner and Jackson, 2002)
(MOR 1170) tibia (MOR online)
(MOR coll.) caudal series (Wolff, Varricchio and Hanna, 2015)
(YPM PU 22445) (YPM online)
(YPM PU 23246-23248) (YPM online)
(YPM PU 22544) (Hirsch and Quinn, 1990)
(YPM PU 22594) (Hirsch and Quinn, 1990)
(YPM PU 23259) (YPM online)
(YPM PU 23408) (YPM online)
(YPM PU 23409) (YPM online)
teeth (Redman, Moore and Varricchio, 2015)
Diagnosis- (after Currie, 1987; compared to Saurornithoides and Zanabazar) round anterior border of antiorbital fenestra; sculpturing less extensive on nasal process of maxilla; postorbital region of skull longer; no sulcus between parasphenoid capsule and rectangular platform between basipterygoid processes; mesethmoid located further anteriorly; very strong, caudoventrally shifted basal tubera; otic recess extends further posteroventrally; dentary symphysis more extensive; mesial serrations extend to tip of carina on maxillary teeth.
Comments- The supposed Struthiomimus manual ungual in plate XV figure 10-11 of Lambe (1902) is not ornithomimid and may be a Troodon pedal ungual II instead. Found with this and apparently similar unguals and manual phalanges were an astragalus, calcaneum, pedal phalanges and two elements identified by Lambe as distal ends of metacarpal I and metatarsal I. A metatarsal I would exclude ornithomimids from consideration, but a calcaneum would exclude troodontids. It's probable some material was incorrectly associated or misidentified. Though Britt described the posterior cervical vertebrae RTMP 81.37.15 and 92.36.1212 as ornithomimids, Makovicky (1995) indicated they were actually Troodon.
Ornithischian or theropod?- Troodon was originally identified as a lizard by Leidy (1856) based on the holotype tooth, but reidentified as a theropod by Cope (1877). Nopcsa (1901) and Hay (1902) placed it in Megalosauridae. Brown (1908) placed it in Ankylosauridae, while Gilmore (1924) believed it was a pachycephalosaurid and a senior synonym of Stegoceras. Thus pachycephalosaurs were classified under Gilmore's new family Troodontidae until Sternberg (1945) placed Troodon back in Theropoda and named Pachycephalosauridae. Russell (1948) described a partial dentary (ROM 1445) of Troodon, assigning it to Troodontidae within the Theropoda. A further confusion with ornithischians occured when Galton (1983) suggested "Laosaurus" minimus should be assigned to Troodon and that the latter is a carnivorous ornithopod (first suggested by Baird, 1981). Galton cited pers. comm. with Horner alluding to undescribed Two Medicine Formation material. The latter turned out to be adults of the ornithopod Orodromeus (Horner and Weishampel, 1988) associated with Troodon teeth, eggs and embryos (Horner and Weishampel, 1996). The idea of Troodon as a carnivorous ornithopod was never established in the technical literature, but was widespread in the popular literature in the 1980's. Instead, it was almost always assigned to Theropoda after 1945.
Laelaps cristatus- Cope (1876) described two teeth as a new species of Laelaps (in which he placed all Judithian theropods). Once Marsh provided the replacement name Dryptosaurus for the preoccupied Laelaps, Hay (1902) moved cristatus to that genus. Osborn (1902) meanwhile referred it to Deinodon, though this is not the same taxon as Hay's (1902) Deinodon cristatus, which was a new combination of Aublysodon cristatus, a tyrannosaurid premaxillary tooth. Matthew and Brown (1922) questionably referred the species to their new genus Dromaeosaurus, probably based on size, for it was the smallest of their 'deinodontids'. Olshevsky (1995) most recently referred it to Troodon, though most workers have ignored it. This tooth can indeed be identified as Troodon by its large serrations (2/mm distally, and slightly smaller mesially), presence of mesial serrations and absence of longitudinal ridges. The size (FABL 6 mm) and BW/FABL (.50) are also comparable to Troodon maxillary teeth (Currie et al., 1990), as is the height/FABL (1.83). The serrations are smaller than in premaxillary teeth, which is why Cope kept it separate from Troodon (at the time only known from the type premaxillary tooth). The tooth is larger than dentary teeth, posterior examples of which also differ in lacking mesial serrations. As it is from the same formation as T. formosus and lacks distinguishing characters, it is referred to that species here.
Polyodontosaurus grandis- Sternberg collected a dentary (CMN 8540) from the same formation as Leidy's specimen, which Gilmore (1932) described as a new genus of lizard- Polyodontosaurus. Sternberg later (1951) assigned this genus to Troodontidae, noting it may be congeneric with Troodon. The latter synonymization was formalized by Romer in 1966, who assigned both to the Coeluridae. On the other hand, Russell (1969) synonymized Polyodontosaurus with Stenonychosaurus inequalis in the Troodontidae.
Stenonychosaurus and Saurornithoides- Sternberg (1932) named Stenonychosaurus inequalis as a coelurid, based on a fragmentary skeleton (CMN 8539). Sternberg later (1951) suggested Stenonychosaurus and Troodon might be synonymous, but no comparable elements were known which could prove this. Russell (1969) described several specimens found in 1968 as Stenonychosaurus inequalis, assigning it to the Troodontidae along with Saurornithoides and Troodon. He did not synonymize Troodon with Stenonychosaurus or Saurornithoides due to the fragmentary condition of the former. Ostrom (1969) assigned both Saurornithoides and Stenonychosaurus to the Dromaeosauridae based on their raptorial second pedal digit, though perhaps deserving subfamilial status. Barsbold (1974) noted differences between the holotype of Troodon and teeth of Saurornithoides, while feeling the cranial and postcranial resemblences between Stenonychosaurus and Saurornithoides justified a close relationship. He assigned the latter two genera to his new family Saurornithoididae, while retaining Troodon in Troodontidae. This was followed until Currie (1987). Sues (1977) described two new dentaries as saurornithoidids, though he was uncertain if they belonged to Stenonychosaurus or Saurornitholestes (which was assigned to Dromaeosauridae once he described it the next year). Stenonychosaurus was generally used for the Dinosaur Park troodontid through the 1980's (e.g. Currie, 1985), though Carpenter (1982) synonymized it with Saurornithoides, as Saurornithoides inequalis. This was done without justification however, referencing a Carpenter and Paul in prep. publication which never emerged. Paul did later (1988) synonymize Saurornithoides with Troodon (including Stenonychosaurus), but this is a subjective decision which has not been accepted by later authors.
Estes (1964) originally referred several teeth from the Lance Formation of Wyoming to Saurornithoides sp.. Carpenter (1982) named Pectinodon bakkeri from the same formation, believing some of Estes' specimens to be referrable to that species, some to his new combination Saurornithoides inequalis, and others to an unnamed third taxon. He assigned Pectinodon to the Saurornithoididae.
Currie's breakthrough- Currie (1987) cleared up the American troodontid situation, determining the differences between known dentaries were ontogenetic, and dental differences between Troodon, ROM 1445, Saurornithoides and the Lance Formation specimens were largely due to variation within the tooth row. Troodon's holotype is a premaxillary tooth, the teeth of Saurornithoides which Barsbold compared were maxillary (as were Carpenter's Saurornithoides inequalis examples), Pectinodon was based on posterior dentary teeth, while ROM 1445 contains a few dentary teeth. Currie described intermediates between all of these morphologies, although he noted the maxillary mesial serrations are more extensive in Troodon than Saurornithoides, extending to the tip of the tooth. He synonymized Stenonychosaurus inequalis and Polyodontosaurus grandis with Troodon formosus, and provisionally did the same for Pectinodon bakkeri. This has remained the consensus, along with the assignment of Saurornithoides, Troodon and related taxa to the Troodontidae.
Overlumped?- Recently the concept of all Campanian-Maastrichtian North American troodontids being one taxon has been questioned. Currie et al. (1990) noted that though Horseshoe Canyon Formation troodontid teeth are essentially identical to those from the Judith River Group/Formation, teeth from the Frenchman, Hell Creek, Lance, Prince Creek and Scollard Formations are different and may prove to be separate species. Baszio (1997) elaborated, describing differences between teeth from the Judith River, Horseshoe Canyon and Scollard Formations. Olshevsky (1991) created the new combination Troodon bakkeri for the Lance Formation material, while several papers have used the combination Troodon inequalis for the Dinosaur Park Formation taxon (Snively, 2002; Osmolska, 2004; Currie, 2005). Currie (2005) stated that it is more conservative to retain inequalis for Dinosaur Park specimens, but keeping taxa separate based on a political boundary (Montana vs. Alberta) has no biological value. Morhardt et al. (2013) examined Dinosaur Park and Two Medicine braincases and found "two distinct morphologies associated with the occipital sinus, in one case being 'peaked' (dorsally extended, mediolaterally compressed) and the other case being 'rounded' (dorsal surface gently curves, shows no dorsal extension, and is not mediolaterally compressed)." The peaked morphology was said to be more similar to Zanabazar. Sankey et al. (2002) have split Dinosaur Park Formation troodontids into Troodon formosus and cf. Troodontidae indet., with the latter being a rare form only present in some formations and distinguished by various dental characters. If they are correct, most of the non-dental specimens (including the Stenonychosaurus holotype and CMN 12340) could not be definitively assigned to either taxon, and many poorly or undescribed Troodon teeth could end up not being referrable to that genus.
Troodon eggs and embryos- Horner (1982) first reported ten nests in the Two Medicine Formation which he ascribed to ornithopods, "closely allied to the Hypsilophodontidae". Horner and Weishampel later (1988) described a new genus of ornithopod from the site, Orodromeus makelai. They believed abundant nest with eggs and embryos belonged to Orodromeus, though this was disproven by Horner and Weishampel (1996) due to the small size of adult Orodromeus and the reidentification of an embryo as Troodon. Zelenitsky and Hillis (1996) named eggs from the Oldman Formation of Alberta Prismatoolithus levis (Prismatoolithidae), while Zelenitsky (2000) identified the Two Medicine Formation Troodon eggs as belonging to this oospecies as well. Most of the publications dealing with Troodon since that time have concerned these nests, eggs and embryos.
One confusing aspect is that Continuoolithus canadensis eggs were provisionally assigned to Troodon by Horner (1984), based on an embryo. This was followed by Hirsch and Quinn (1990) and Horner (1994), until 1996. Horner (1997) found the embryo to be indeterminate, while Varricchio and Jackson (2004) found the eggshell to be theropod. The precise identity of Continuoolithus is still unknown.
Reinterpreted records- Although Currie et al. (1990) reported Troodon from the Milk River Formation, Baszio (1997) notes the ROM specimens noted were collected in the Milk Creek area, but probably in the Judith River Group. A large sample of theropod teeth from the Milk River Formation did not include Troodon.
Rowe et al. (1992) and Sankey (1997, 1998) identified Troodon in the Aguja Formation of Texas based on teeth (TMM 43057-323 and LSUMG 140:6117 respectively), but these were later identified as pachycephalosaurian by Sankey (2001). This would mean Troodon is unknown from the Aguja Formation, except that Montellano et al. (2009) later reported cf. Troodon teeth in an abstract. Whether these are truly troodontid awaits proper description.
References- Leidy, 1856. Notices of remains of extinct reptiles and fishes, discovered by Dr. F. V. Hayden in the bad lands of the Judith River, Nebraska Territory. Proceedings of the Academy of Natural Sciences of Philadelphia. 8, 72-73.
Cope, 1876. On some extinct reptiles and Batrachia from the Judith River and Fox Hills Beds of Montana. Proceedings of the Academy of Natural Sciences of Philadelphia. 28, 340-359.
Cope. 1877. Report on the geology of the region of the Judith River, Montana, and on vertebrate fossils obtained on or near the Missouri River. Bulletin of the United States Geological and Geographical Survey. 3(3), 565-597.
Nopcsa, 1901. Synopsis un Abstammung der Dinosaurier. Foldtani Kozlony (Budapest). 31, 247-288.
Hay, 1902. Bibliography and Catalogue of Fossil Vertebrata of North America. U.S. Geological Survey Bulletin. 179, 868 pp.
Lambe, 1902. New genera and species from the Belly River Series (mid-Cretaceous). Contributions to Canadian Palaeontology, Geological Survey of Canada. 3, 23-81.
Osborn, 1902. On Vertebrata of the Mid-Cretaceous of the Northwest Territory. I: Distinctive characters of the Mid-Cretaceous fauna. Contrib. Canad. Pal. III. 1-21.
Matthew and Brown, 1922. The family Deinodontidae, with notice of a new genus from the Cretaceous of Alberta. Bulletin of the American Museum of Natural History. 46(6), 367-385.
Gilmore, 1924. On Troodon validus, an orthopodous dinosaur from the Belly River Cretaceous of Alberta, Canada. Department of Geology, University of Alberta Bulletin. 1, 1-43.
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Sternberg, 1932. Two new theropod dinosaurs from the Belly River Formation of Alberta. Canadian Field-Naturalist. 46(5), 99-105.
Russell, 1948. The dentary of Troödon, a genus of theropod dinosaurs. Journal of Paleontology. 22(5), 625-629.
Sternberg, 1945. Pachycephalosauridae proposed for domeheaded dinosaurs, Stegoceras lambei n. sp., described. Journal of Paleontology. 19, 534-538.
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Estes, 1964. Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming. University of California Publications in Geological Sciences. 49, 1-180.
Romer, 1966. Vertebrate Paleontology, 3rd edition. University of Chicago Press, Chicago. 1-468.
Ostrom, 1969. Osteology of Deinonychus antirrhopus, an unusual theropod from the Lower Cretaceous of Montana. Peabody Museum of Natural History Bulletin. 30, 1-165.
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Sahni, 1972. The vertebrate fauna of the Judith River Formation, Montana. Bulletin of the AMNH. 147.
Barsbold, 1974. Saurornithoididae, a new family of small theropod dinosaurs from Central Asia and North America. Palaeontologia Polonica. 30, 5-22.
Sues, 1977. Dentaries of small theropods from the Judith River Formation (Campanian) of Alberta, Canada. Canadian Journal of Earth Sciences. 14, 587-592.
Baird, 1981. Princeton University. Society of Vertebrate Paleontology News Bulletin. 121, 21-22.
Carpenter, 1982. Baby dinosaurs from the Late Cretaceous Lance and Hell Creek formations and a description of a new species of theropod. Contributions to Geology, University of Wyoming. 20(2), 123-134.
Horner, 1982. Evidence for colonial nesting and "site fidelity" among ornithischian dinosaurs. Nature. 297, 675-676.
Galton, 1983. The cranial anatomy of Dryosaurus, a hypsilophodontid dinosaur from the Upper Jurassic of North America and East Africa, with a review of hypsilophodontids from the Upper Jurassic of North America. Geologica et Palaeontologica. 17, 207-243.
Horner, 1984. The nesting behavior of dinosaurs. Scientific American. 250, 130-137.
Currie, 1985. Cranial anatomy of Stenonychosaurus inequalis (Saurischia, Theropoda) and its bearing on the origin of birds. Canadian Journal of Earth Sciences. 22(1), 643-658.
Wilson and Currie, 1985. Stenonychosaurus inequalis (Saurischia: Theropoda) from the Judith River (Oldman) Formation of Alberta: new findings on metatarsal structure. Canadian Journal of Earth Sciences. 22(1), 813–817.
Currie, 1987. Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia). Journal of Vertebrate Paleontology. 7, 72-81.
Currie, 1987. Theropods of the Judith River Formation. Occasional Paper of the Tyrrell Museum of Palaeontology. 3, 52-60.
Horner and Weishampel, 1988. A comparative embryological study of two ornithischian dinosaurs. Nature. 332, 256-257.
Fiorillo, 1989. The vertebrate fauna from the Judith River Formation (Late Cretaceous) of Wheatland and Golden Valley Counties, Montana. The Mosasaur. 4, 127-142.
Brinkman, 1990. Paleoecology of the Judith River Formation (Campanian) of Dinosaur Provincial Park, Alberta, Canada: Evidence from vertebrate microfossil localities. Palaeogeography, Palaeoclimatology, Palaeoecology. 78, 37-54.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Hirsch and Quinn, 1990. Eggs and eggshell fragments from the Upper Cretaceous Two Medicine Formation of Montana. Journal of Paleontology. 10, 491-511.
Olshevsky, 1991. A Revison of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodyila. Mesozoic Menanderings #2 (1st printing). iv + 196pp.
Varricchio and Currie, 1991. New theropod finds from the Two Medicine Formation (Campanian) of Montana. Journal of Vertebrate Paleontology. 11(3), 59A.
Rowe, Ciffelli, Lehman and Weil, 1992. The Campanian Terlingua local fauna, with a summary of other vertebrates from the Aguja Formation, Trans-Pecos, Texas. Journal of Vertebrate Paleontology. 12, 472-493.
Varricchio, 1992. Taphonomy and Histology of the Upper Cretaceous Theropod Dinosaur Troodon formosus: Life history Implications. Journal of Vertebrate Paleontology. 12(3), 57A.
Britt, 1993. Pneumatic postcranial bones in dinosaurs and other archosaurs. PhD Thesis, University of Calgary (Canada), Alberta.
Currie and Zhao, 1993. A new troodontid (Dinosauria, Theropoda) braincase from the Dinosaur Park Formation (Campanian) of Alberta. Canadian Journal of Earth Sciences. 30(10-11), 2234-2247.
Varricchio, 1993. Bone microstructure of the Upper Cretaceous theropod dinosaur Troodon formosus. Journal of Vertebrate Paleontology. 13(1), 99-104.
Fiorillo and Currie, 1994. Theropod teeth from the Judith River Formation (Upper Cretaceous) of south-central Montana. Journal of Vertebrate Paleontology. 14(1), 74-80.
Horner, 1994. Comparative taphonomy of some dinosaur and extant bird colonial nesting grounds. in Carpenter, Hirsch and Horner (eds.). Dinosaur Eggs and Babies. Cambridge University Press. 116-123.
Makovicky, 1995. Phylogenetic aspects of the vertebral morphology of Coelurosauria (Dinosauria: Theropoda). M.S. thesis, Univ. Copenhagen, 311pp.
Olshevsky, 1995. The origin and evolution of the tyrannosaurids. Kyoryugaku Saizensen [Dino-Frontline]. 9, 92-119 (part 1); 10, 75-99 (part 2) [in Japanese].
Horner Weishampel, 1996. A comparative embryological study of two ornithischian dinosaurs - a correction. Nature. 383, 103.
Zelenitsky and Hills, 1996. An egg clutch of Prismatoolithus levis oosp. nov. from the Oldman Formation (Upper Cretaceous), Devil’s Coulee, southern Alberta. Canadian Journal of Earth Science. 33(1), 127-131.
Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Horner, 1997. Rare preservation of an incompletely ossified fossil embryo. Journal of Vertebrate Paleontology. 17, 431-434.
Sankey, 1997. Late Cretaceous vertebrate paleontology and Paleoecology, Upper Aguja Formation, Big Bend National Park, Texas. Journal of Vertebrate Paleontology. 17(3), 73A.
Varricchio, Jackson, Borkowski and Horner, 1997. Nest and egg clutches of the dinosaur Troodon formosus and the evolution of avian reproductive traits. Nature. 385, 247-250.
Carrano, 1998. The evolution of dinosaur locomotion: Functional morphology, biomechanics, and modern analogs. PhD Thesis, The University of Chicago. 424 pp.
Sankey, 1998. Vertebrate paleontology and magnetostratigraphy of the upper Aguja Formation (late Campanian), Talley Mountain area, Big Bend National Park, Texas. Unpublished Ph.D. dissertation. Louisiana State University, Baton Rouge. 263 pp.
Varricchio, Jackson and Trueman, 1999. A nesting trace with eggs for the Cretaceous theropod dinosaur Troodon formosus. Journal of Vertebrate Paleontology. 19, 91-100.
Varricchio and Jackson, 2000. Physiological implications of reproductive behavior in the dinosaur Troodon formosus. Journal of Vertebrate Paleontology. 20(3), 75A.
Zelenitsky, 2000. Dinosaur eggs from Asia and North America. Journal of the Paleontological Society of Korea, Special Publication. 4, 13-26.
Horner, Padian and de Ricqles, 2001. Comparative osteohistology of some embryonic and perinatal archosaurs: developmental and behavioral implications for dinosaurs. Paleobiology. 27, 39-58.
Hutchinson, 2001. The evolution of pelvic osteology and soft tissues on the line to extant birds (Neornithes). Zoological Journal of the Linnean Society. 131, 123-168.
Hutchinson, 2001. The evolution of femoral osteology and soft tissues on the line to extant birds (Neornithes). Zoological Journal of the Linnean Society. 131, 169-197.
Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
Sankey, 2001. Late Campanian southern dinosaurs, Aguja Formation, Big Bend, Texas. Journal of Vertebrate Paleontology. 75(1), 208-215.
Varricchio, 2001. "Beautiful wounding tooth": ontogeny and osteology in the theropod Troodon formosus. Journal of Vertebrate Paleontology. 21(3), 110A.
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Snively and Russell, 2002. Kinematic model of tyrannosaurid (Dinosauria: Theropoda) arctometatarsus function. 255(2), 215-227.
Zelenitsky, Modesto and Currie, 2002. Bird-like characteristics of troodontid theropod eggshell. Cretaceous Research. 23, 297-305.
Ryan, 2003. Taxonomy, systematics and evolution of centrosaurine ceratopsids of the Campanian Western Interior basin of North America. Unpublished PhD thesis. Department of Biological Sciences, Calgary, Alberta. 578pp.
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T? bakkeri (Carpenter, 1982) Olshevsky, 1991
= Pectinodon bakkeri Carpenter, 1982
Late Maastrichtian, Late Cretaceous
Lance Formation, Montana, Wyoming, US

Holotype- (UCM 38445; holotype of Pectinodon bakkeri) tooth (6.2 mm)
Paratypes- (UCM 38446) (juvenile) tooth (1.8 mm)
(UCM 73098) (juvenile) tooth (2.8 mm)
(UCMP 125239) (juvenile) tooth (3.2 mm)
Referred- (CMN 30748) partial humerus, ulna, femora, tibia (McIntosh, 1981)
(SDSM 12456) four dentary teeth (Whitmore, 1988)
(SDSM 12458) maxillary tooth (Whitmore, 1988)
(SDSM 15098) three dentary teeth (Whitmore, 1988)
(SDSM 15099) maxillary tooth (Whitmore, 1988)
(UA 156) tooth (Baszio, 1997)
(UA 157) tooth (Baszio, 1997)
(UCM 41666) (juvenile) anterior dentary (Carpenter, 1982)
(UCM 43218) (juvenile) basioccipital (Carpenter, 1982)
(UCMP 84990) tooth (UCMP online)
(UCMP 125240) tooth (Carpenter, 1982)
(UCMP 125241) tooth (Carpenter, 1982)
(UCMP 125242) tooth (Carpenter, 1982)
(UCMP 125243) tooth (Carpenter, 1982)
(UCMP 125244) tooth (Carpenter, 1982)
(UCMP 125245) tooth (Carpenter, 1982)
(UCMP 125246) tooth (Carpenter, 1982)
(UCMP 125247) tooth (Carpenter, 1982)
(UCMP 186864) teeth (UCMP online)
(UCMP 186886) teeth (UCMP online)
(UCMP 186916) tooth (UCMP online)
(UCMP 186979) tooth (UCMP online)
(UCMP 187050-187056) seven teeth (UCMP online)
(UCMP 187058-187079) twenty-two teeth (UCMP online)
(UCMP 187180) tooth (UCMP online)
(UCMP 187181) tooth (UCMP online)
(UCMP 214059) tooth (UCMP online)
(YPM 54491) (YPM online)
(YPM 55041) (YPM online)
(YPM 55521) (YPM online)
(YPM 55536) (YPM online)
(YPM 55545) (YPM online)
(YPM 55546) (YPM online)
(YPM 55583) (YPM online)
(YPM 55584) (YPM online)
(YPM 55591) (YPM online)
(YPM 55592) (YPM online)
(YPM 55627) (YPM online)
teeth (Derstler, 1995)
(juvenile) elements, eggshells (Derstler, 1995)
teeth (Spencer, Turner and Chadwick, 2001)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, South Dakota, US

teeth (DePalma, 2010)
Comments- Estes (1964) referred teeth to Saurornithoides sp., but these seem to belong to a different species of troodontid (cf. Troodontidae indet. of Sankey et al., 2002). Carpenter (1982) described several teeth as Pectinodon bakkeri, believing them to be distinct from Judith River troodontids, though Currie showed this was due to their position in the jaw (posterior dentary). Virtually no Lance Formation troodontid material has been described except this material, which Currie (1987) felt was indistinguishable from Judith River Troodon, though Currie et al. (1990) stated they were somewhat different. Derstler (1995) considered his juvenile material and eggshells to belong to a new taxon of troodontid. Olshevsky (1991) created the new combination Troodon bakkeri for Lance Formation troodontid teeth, which is used here because the basal tubera are large and the dentary symphysis seems more robust than Zanabazar, though not as much as in T. formosus (due to ontogeny?).
References- Estes, 1964. Fossil vertebrates from the Late Cretaceous Lance Formation, eastern Wyoming. University of California Publications in Geological Sciences. 49, 1-180.
McIntosh, 1981. Annotated catalogue of the dinosaurs (Reptilia, Archosauria) in the Collections of Carnegie Museum of Natural History. Bulletin of the Carnegie Museum of Natural History. 18, 1-67.
Carpenter, 1982. Baby dinosaurs from the Late Cretaceous Lance and Hell Creek formations and a description of a new species of theropod. Contributions to Geology, University of Wyoming. 20(2), 123-134.
Currie, 1987. Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia). Journal of Vertebrate Paleontology. 7, 72-81.
Whitmore, 1988. The vertebrate paleontology of Late Cretaceous (Lancian) localities in the Lance Formation, Northern Niobrara County, Wyoming. Unpublished Masters Thesis. South Dakota School of Mines and Technology, Rapid City, South Dakota. 130pp.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Olshevsky, 1991. A Revison of the Parainfraclass Archosauria Cope, 1869, Excluding the Advanced Crocodyila. Mesozoic Menanderings #2 (1st printing). iv + 196pp.
Derstler, 1995. The Dragons’ Grave - an Edmontosaurus bonebed containing theropod egg shells and juveniles, Lance Formation, (Uppermost Cretaceous), Niobrara County, Wyoming: Journal of Vertebrate Paleontology. 15(3), 26A.
Spencer, Turner and Chadwick, 2001. A remarkable vertebrate assemblage from the Lance Formation, Niobrara County, Wyoming. GSA Annual Meeting and Exposition Abstracts. 33(6), A-197.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.
DePalma, 2010. Geology, taphonomy, and paleoecology of a unique Upper Cretaceous bonebed near the Cretaceous-Tertiary boundary in South Dakota. Masters thesis, University of Kansas. 227 pp.
T. sp. nov. (Currie, 1987)
Middle Maastrichtian, Late Cretaceous
Horseshoe Canyon Formation, Alberta, Canada

(RTMP 74.1.1) tooth (6.3x4.6x2.5 mm) (Larson and Currie, 2013)
(RTMP 74.1.2) tooth (8.4x6.2x3.4 mm) (Larson and Currie, 2013)
(RTMP 83.12.11) anterior dentary, four teeth (Currie, 1987)
(RTMP 83.45.5) tooth (7.5x5.7x3.2 mm) (Larson and Currie, 2013)
(RTMP 83.45.6) tooth (7.4x5.9x3.5 mm) (Larson and Currie, 2013)
(RTMP 85.12.2) tooth (4.1x3.5x1.7 mm) (Larson and Currie, 2013)
(RTMP 85.30.32) tooth (5.4x3.1x1.4 mm) (Larson and Currie, 2013)
(RTMP 85.31.19) tooth (6.6x5.3x2.8 mm) (Larson and Currie, 2013)
(RTMP 87.12.14) tooth (7.8x5.3x2.8 mm) (Larson and Currie, 2013)
(RTMP 87.12.19) tooth (7.4x6.1x3.3 mm) (Larson and Currie, 2013)
(RTMP 88.96.2) tooth (8.4x6.3x3.3 mm) (Larson and Currie, 2013)
(RTMP 88.96.7) tooth (8.9x6.3x3.1 mm) (Larson and Currie, 2013)
(RTMP 89.125.14) tooth (4.5x2.4x2 mm) (Larson and Currie, 2013)
(RTMP 90.82.24) tooth (7.8x6x3.3 mm) (Larson and Currie, 2013)
(RTMP 90.82.25) tooth (4.9x3.4x1.6 mm) (Larson and Currie, 2013)
(RTMP 90.82.26) tooth (7.3x5.5x3.1 mm) (Larson and Currie, 2013)
(RTMP 93.12.13) tooth (7x5.53.3 mm) (Larson and Currie, 2013)
(RTMP 94.9.4) tooth (7.4x5.7x2.8 mm), tooth (6.1x5.5x2.8 mm) (Larson and Currie, 2013)
(RTMP 95.2.23) tooth (6.2x5.5x2.5 mm) (Larson and Currie, 2013)
(RTMP 96.29.29) posterior maxillary tooth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP 97.7.3) tooth (7x5.5x3.2 mm) (Larson and Currie, 2013)
(RTMP 97.39.3) posterior dentary tooth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP 97.39.5) dentary tooth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP 97.39.7) posterior premaxillary or anterior maxillary tooth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP 97.77.4) tooth (7x5.6x3.4 mm) (Larson and Currie, 2013)
(RTMP 98.63.43) tooth (10.7x6.1x3.6 mm) (Larson et al., 2010)
(RTMP 98.68.156) tooth (8.5x6.4x3.2 mm), tooth (7.6x5.8x3 mm), tooth (8.1x5.6x3.2 mm) (Larson and Currie, 2013)
(RTMP 99.50.114) tooth (6.8x5.6x3.7 mm) (Larson et al., 2010)
(RTMP 99.50.115) tooth (10.7x5.8x3.7 mm) (Larson et al., 2010)
(RTMP 2000.45.10) tooth (Larson et al., 2010)
(RTMP 2000.45.24) tooth (4.4x3.6x2.2 mm) (Larson et al., 2010)
(RTMP 2000.45.41) tooth (Larson et al., 2010)
(RTMP 2000.45.90) tooth (5.2x3.5x2 mm) (Larson et al., 2010)
(RTMP 2000.45.91) tooth (10x5.4x3.4 mm) (Larson et al., 2010)
(RTMP 2001.45.80) tooth (12.1x7x4.1 mm) (Larson et al., 2010)
(RTMP 2001.45.81) tooth (6.6x4.8x2.8 mm) (Larson et al., 2010)
(RTMP 2002.45.48) tooth (7.7x5.6x? mm) (Larson et al., 2010)
(RTMP 2003.45.57) tooth (Larson et al., 2010)
(RTMP 2003.45.58) tooth (7.1x5x2.7 mm) (Larson et al., 2010)
(RTMP 2003.34.1) tooth (Larson et al., 2010)
(RTMP 2009.122.1) tooth (9.4x6.3x3.7 mm) (Larson and Currie, 2013)
(RTMP coll.) six teeth (Baszio, 1997)
(RTMP coll.) nine premaxillary teeth, thirty-nine maxillary teeth, thirteen dentary teeth (Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998)
(RTMP or UALVP coll.) metatarsal (Eberth and Currie, 2010)
(UALVP 48639) tooth (9.5x?x2.8 mm), tooth (9.3x6x3.3 mm), tooth (9.5x6.2x3.7 mm) (Torices et al., 2014)
(UALVP 53921) tooth (10x6.2x3.7 mm) (Torices et al., 2014)
(UALVP 55456) tooth (7.4x5.7x3.3 mm) (Torices et al., 2014)
(UALVP 55489) tooth (10x6.2x3.6 mm) (Torices et al., 2014)
Comments- Currie (1987) described a dentary with teeth that can be referred to Troodon because of its extensive mandibular symphysis. Although Currie et al. (1990) state Horseshoe Canyon Formation teeth are essentially identical to Judith River teeth, Baszio (1997) notes they are are generally smaller than Dinosaur Park (Judith River) T. formosus, but identical in morphology. Ryan et al. (1998) state they could not distinguish Horseshoe Canyon teeth from Judith River teeth, but referred to the former as Troodon sp. due to the stratigraphic difference. Similarly, Torices et al. (2014) could not distinguish Horseshoe Canyon and Dinosaur Park teeth statistically. However, Larson and Currie (2013) found "troodontid teeth from the Horseshoe Canyon Formation are distinct from the Dinosaur Park Formation teeth."
References- Currie, 1987. Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia). Journal of Vertebrate Paleontology. 7, 72-81.
Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Ryan, Currie, Gardner and Livigne, 1997. Baby hadrosaurid material associated with an unusually high abundance of troodontid teeth from the Horseshoe Canyon Formation (Early Maastrichtian), Alberta, Canada. Journal of Vertebrate Paleontology. 17(3), 72A.
Ryan, Currie, Gardner, Vickaryous and Lavigne, 1998. Baby hadrosaurid material associated with an unusually high abundance of Troodon teeth from the Horseshoe Canyon Formation, Upper Cretaceous, Alberta, Canada. Gaia. 15, 123-133.
Evans, Lam, Maddin and Conacher, 2003. Taphonomy of the Prehistoric Park Quarry, Horseshoe Canyon Formation, Drumheller, Alberta. Alberta Palaeontological Society, Seventh Annual Symposium, "Fossils in Motion" Abstracts. 25-28.
Eberth and Currie, 2010. Stratigraphy, sedimentology, and taphonomy of the Albertosaurus bonebed (upper Horseshoe Canyon Formation; Maastrichtian), southern Alberta, Canada. Canadian Journal of Earth Sciences. 47(9), 1119-1143.
Larson, Brinkman and Bell, 2010. Faunal assemblages from the upper Horseshoe Canyon Formation, an early Maastrichtian cool-climate assemblage from Alberta, with special reference to the Albertosaurus sarcophagus bonebed. Canadian Journal of Earth Sciences. 47(9), 1159-1181.
Larson and Currie, 2013. Multivariate analyses of small theropod dinosaur teeth and implications for paleoecological turnover through time. PloS ONE. 8(1), e54329.
Torices, Funston, Kraichy and Currie, 2014. The first appearance of Troodon in the Upper Cretaceous site of Danek Bonebed, and a reevaluation of troodontid quantitative tooth morphotypes. Canadian Journal of Earth Sciences. 51(11), 1039-1044.
T. sp. nov. (Baszio, 1997)
Late Maastrichtian, Late Cretaceous
Scollard Formation, Alberta, Canada

(RTMP 94.106.1) tooth (Ryan and Russell, 2001)
(UA 109) tooth (Baszio, 1997)
teeth (Ryan and Russell, 2001)
Comments- Baszio (1997) reported UA 109 was similar to Judith River T. formosus in size, but differed in having larger mesial serrations (up to three times wider than distal serrations).
References- Baszio, 1997. Investigations on Canadian dinosaurs: systematic palaeontology of isolated dinosaur teeth from the Latest Cretaceous of south Alberta, Canada. Courier Forschungsinstitut Senckenberg. 196, 33-77.
Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
T. sp. (Currie, Rigby and Sloan, 1990)
Campanian, Late Cretaceous
Prince Creek Formation, Alaska, US

Material- (AK83-V-095) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK138-V-128) (subadult) partial braincase (Fiorillo et al., 2009)
(AK233-V-054) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK282-V-001) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK282-V-010) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK282-V-052) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK282-V-056) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK283-V-017) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK283-V-115) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK284-V-024) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK285-V-008) premaxillary tooth (Fiorillo and Gangloff, 2000)
(AK285-V-013) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK285-V-037a) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK299-V-134) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-017) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-021) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-042) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-055) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-060) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK300-V-129) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK335-V-012FT) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK335-V-076) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK382-V-015) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK382-V-105) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK383-V-018) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK383-V-137) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK383-V-140) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK383-V-176) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK383-V-183) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK385-V-001) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK385-V-002) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK387-V-000FT) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK387-V-017) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK388-V-002) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK388-V-082) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK392-V-007) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK459-V-011) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK498-V-001) tooth (Fiorillo, 2008)
(AK490-V-004) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK490-V-008FL) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK490-V-086FT) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK491-V-143) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK491-V-168) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK497-V-002) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK498-V-001) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK498-V-002) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK498-V-003) maxillary or dentary tooth (Fiorillo and Gangloff, 2000)
(AK coll.) thirty-three teeth (Fiorillo, 2008)
(DMNH 22158) (adult) partial braincase (Fiorillo et al., 2009)
(UCMP 140624; lost) three teeth (UCMP online)
skull fragments (Gangloff, 1998)
Comments- The two braincases were described as T. formosus, apparently identical to that species except for some pneumatic features, which are known to exhibit marked individual and symmetry variation. These teeth have not been described in detail, though Currie et al. (1990) noted they were somewhat different than Judith River Troodon teeth, and Sankey et al. (2002) said that no examples of their cf. Troodontidae indet. were present in this formation. Fiorillo (2008) found the teeth to be larger on average than T. formosus (9.78 mm in length vs. 4.96 mm), but indentical in length vs. FABL. The Alaskan teeth range from 5.4-14.3 mm in length and 4.3-9 mm in FABL.
References- Currie, Rigby and Sloan, 1990. Theropod teeth from the Judith River Formation of southern Alberta, Canada. in Carpenter and Currie (eds.). Dinosaur Systematics: Perspectives and Approaches. Cambridge University Press, New York. pp. 107-125.
Nelms, 1992. Paleoecological implications of a North Slope Dinosaurian assemblage. International Conference on Arctic Margins, Abstracts. 42.
Gangloff, 1998. Arctic Dinosaurs with Emphasis on the Cretaceous Record of Alaska and the Eurasian-North American Connection. Kirkland, Lucas and Estep (eds). Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science, Bulletin. 14, 211-220.
Fiorillo and Gangloff, 2000. Theropod teeth from the Prince Creek Formation (Cretaceous) of Northern Alaska, with speculations on Arctic dinosaur paleoecology. Journal of Vertebrate Paleontology. 20(3), 41A.
Fiorillo and Gangloff, 2000. Theropod teeth from the Prince Creek Formation (Cretaceous) of Northern Alaska, with speculations on Arctic dinosaur paleoecology. Journal of Vertebrate Paleontology. 20(4), 675-682.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.
Fiorillo, 2008. On the occurence of exceptionally large teeth of Troodon (Dinosauria: Saurischia) from the Late Cretaceous of Northern Alaska. Palaios. 23, 322-328.
Fiorillo, Tykoski, Currie, McCarthy and Flaig, 2009. Description of two partial Troodon braincases from the Prince Creek Formation (Upper Cretaceous), North Slope Alaska. Journal of Vertebrate Paleontology. 29(1), 178-187.
T. sp. (Estes, Berberian and Mesozoely, 1969)
Late Maastrichtian, Late Cretaceous
Hell Creek Formation, Montana, South Dakota, US

(FMNH PR2901) tooth (5.9x2.8x1.3 mm) Gates, Zanno and Makovicky, 2015)
(MCZ 3694) tooth (Estes, Berberian and Mesozoely, 1969)
(UCMP 186856) tooth (UCMP online)
(UCMP 186868) teeth (UCMP online)
(UCMP 186873) tooth (UCMP online)
(UCMP 186885) teeth (UCMP online)
(UCMP 186904) tooth (UCMP online)
(UCMP 187057) tooth (UCMP online)
(UCMP 187168-187174) seven teeth (UCMP online)
(UCMP 187178) tooth (UCMP online)
(UCMP 187184) tooth (UCMP online)
(UCMP 187186) tooth (UCMP online)
(UCMP 214060-214062) three teeth (UCMP online)
teeth (Stenerson and O'Conner, 1994)
material (Triebold and Russell, 1995; Triebold, 1997)
material (Jacobson and Sroka, 1998)
four teeth (Larson, Nellermoe and Gould, 2003)
teeth and elements (DePalma, 2010)
Comments- Estes et al. (1969) referred MCZ 3694 to Coeluridae, while Stenerson and O'Conner (1994) called their teeth Saurornithoides sp.. None have been described yet, though the UCMP specimens were identified as Troodon by Sankey. Gates et al. (2015) noted FMNH PR2901 resembles Pectinodon except for its prominent mesial keel.
References- Estes, Berberian and Mesozoely, 1969. Lower vertebrates from the Late Cretaceous Hell Creek Formation, McCone County, Montana. Breviora. 337, 1-33.
Stenerson and O'Conner, 1994. The Late Cretaceous Hell Creek Formation of Northwestern South Dakota and its Fauna. MAPS Digest. 17(4), 108-120.
Triebold and Russell, 1995. A new small dinosaur locality in the Hell Creek Formation: Journal of Vertebrate Paleontology. 15(3), 57A.
Triebold, 1997. The Sandy Site: Small Dinosaurs from the Hell Creek Formation of South Dakota. in Wolberg, Stump and Rosenberg (eds). Dinofest International, Proceedings of a Symposium sponsered by Arizona State University. A Publication of The Academy of Natural Sciences. 245-248.
Jacobson and Sroka, 1998. Preliminary assement of a Hell Creek Dinosaurian Fauna from sites in Corson County, South Dakota. Journal of Vertebrate Paleontology. 18(3), 53A.
Larson, Nellermoe and Gould, 2003. A study of theropod teeth from a low-species-density hadrosaur bone bed in the Lower Hell Creek Formation in Carson, Co., S.D.. Journal of Vertebrate Paleontology. 23(3), 70A-71A.
DePalma, 2010. Geology, taphonomy, and paleoecology of a unique Upper Cretaceous bonebed near the Cretaceous-Tertiary boundary in South Dakota. Masters thesis, University of Kansas. 227 pp.
Gates, Zanno and Makovicky, 2015. Theropod teeth from the upper Maastrichtian Hell Creek Formation "Sue" Quarry: New morphotypes and faunal comparisons. Acta Palaeontologica Polonica. 60(1), 131-139.
T. sp. (Langston, 1975)
Maastrichtian, Late Cretaceous
St. Mary River Formation, Alberta, Canada

(CMN 10649) tooth (Langston, 1975)
(CMN 10674) partial tooth (Langston, 1975)
References- Langston, 1975. The ceratopsian dinosaurs and associated lower vertebrates from the St. Mary River Formation (Maestrichtian) at Scabby Butte, Southern Alberta. Canadian Journal of Earth Science. 12, 1576-1608.
Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
T. sp. (Ryan and Russell, 2001)
Late Campanian, Late Cretaceous
Wapiti Formation, Alberta, Canada

(RTMP 89.55.1008) metatarsal (Ryan and Russell, 2001)
(RTMP 2004.23.3) posterior premaxillary or anterior maxillary tooth (Fanti and Miyashita, 2009)
(UALVP 48749) tooth (5.5x4x2.2 mm) (Torices et al., 2014)
(UALVP 48750) posterior dentary tooth (3.7x3.7x2 mm) (Fanti and Miyashita, 2009)
(UALVP 48753) anterior maxillary tooth (10.8x7.5x3.5 mm) (Fanti and Miyashita, 2009)
(UALVP 48755) premaxillary tooth (4.8x3.1x3.1 mm) (Fanti and Miyashita, 2009)
(UALVP 48757) tooth (8.9x5.9x3.6 mm) (Torices et al., 2014)
(UALVP 48764) tooth (10.8x6.5x3.8 mm) (Torices et al., 2014)
(UALVP 48765) tooth (8.5x5.8x3 mm) (Torices et al., 2014)
(UALVP 48776) tooth (10.5x7.1x3.7 mm) (Torices et al., 2014)
(UALVP 48777) tooth (9.4x7.5x3.6 mm) (Torices et al., 2014)
(UALVP 48779) tooth (11x6.5x3.8 mm) (Torices et al., 2014)
(UALVP 48780) tooth (10.2x6.7x4.8 mm) (Torices et al., 2014)
(UALVP 48785) tooth (8.4x6.3x3.3 mm) (Torices et al., 2014)
(UALVP 52599) tooth (Fanti, Currie and Burns, 2015)
(UALVP 53514) tooth (Fanti, Currie and Burns, 2015)
eighteen teeth (Fanti and Miyashita, 2009)
Comments- Torices et al. (2014) could not statistically distinguish teeth from the Wapiti, Dinosaur Park or Horseshoe Canyon Formations.
References- Ryan and Russell, 2001. The dinosaurs of Alberta (exclusive of Aves). in Tanke and Carpenter (eds.). Mesozoic Vertebrate Life: New Research Inspired by the Paleontology of Philip J. Currie. Indiana University Press, Bloomington, Indiana. pp. 279-297.
Fanti and Miyashita, 2009. A high latitude vertebrate fossil assemblage from the Late Cretaceous of west-central Alberta, Canada: Evidence for dinosaur nesting and vertebrate latitudinal gradient. Palaeogeography, Palaeoclimatology, Palaeoecology. 275, 37-53.
Torices, Funston, Kraichy and Currie, 2014. The first appearance of Troodon in the Upper Cretaceous site of Danek Bonebed, and a reevaluation of troodontid quantitative tooth morphotypes. Canadian Journal of Earth Sciences. 51(11), 1039-1044.
Fanti, Currie and Burns, 2015. Taphonomy, age, and paleoecological implication of a new Pachyrhinosaurus (Dinosauria: Ceratopsidae) bonebed from the Upper Cretaceous (Campanian) Wapiti Formation of Alberta, Canada. Canadian Journal of Earth Sciences. 52(4), 250-260.
T? sp. (Montellano, Monroy, Hernandez-Rivera and Torres, 2009)
Late Campanian, Late Cretaceous
Aguja Formation, Mexico
Material
- teeth
Reference- Montellano, Monroy, Hernandez-Rivera and Torres, 2009. Late Cretaceous microvertebrate fauna from the Northern state of Coahuila, Mexico. Journal of Vertebrate Paleontology. 29(3), 151A.
T? sp. (Hernandez-Rivera, 1997)
Late Campanian, Late Cretaceous
El Gallo Formation, Mexico

Material- (LACM 42637/HJG 689) tooth (Hilton, 2003)
(42675/HJG 696) tooth (Hilton, 2003)
Comments- These were identified as Saurornithoides by Hilton (2003).
References- Hernandez-Rivera, 1997. Mexican Dinosaurs. in Currie and Padian (eds). Encyclopedia of Dinosaurs. Academic Press. 433-437.
Hilton, 2003. Dinosaurs and other Mesozoic reptiles of California. University of California Press. 318pp.
T? sp. (Hall, 1991)
Late Campanian, Late Cretaceous
Fossil Forest Member of the Fruitland Formation, New Mexico, US

Material- (KUVP 96932) tooth
References- Hall, 1991. Lower vertebrate paleontology of the upper Fruitland Formation, Fossil Forest area, New Mexico, and implications for Late Cretaceous terrestrial biostratigraphy. Masters Thesis. University of Kansas. 126 pp.
Williamson and Brusatte, 2014. Small theropod teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and their implications for understanding Latest Cretaceous dinosaur evolution. PLoS ONE. 9(4), e93190.
T? sp. (Wroblewski, 1998)
Late Maastrichtian, Late Cretaceous
Ferris Formation, Wyoming, US

Reference- Wroblewski, 1998. Changing paleoenvironments and paleofaunas across the K-T boundary, Ferris Formation, Southcentral Wyoming. Tate Geological Museum, Casper College, Casper Wyoming. Tate ’98. Life in the Cretaceous. 53-70.
T? sp. (Stokosa, 2005)
Maastrichtian, Late Cretaceous
Fox Hills Formation, South Dakota, US
Material
- (SDSM 14518) dentary tooth
Comments- This tooth was identified by Stoksad (2005) as Troodon cf. formosus. Its macroscopic structure has not been described.
Reference- Stokosa 2005. Enamel microstructure variation within the Theropoda. in Carpenter (ed). The Carnivorous Dinosaurs. 163-178.
T? sp. (Langston, Standhardt and Stevens, 1989)
Late Maastrichtian, Late Cretaceous
Lower Javelina Formation, Texas, US

Reference- Langston, Standhardt and Stevens, 1989. Fossil vertebrate collecting in the Big Bend - History and retrospective. in Vertebrate Paleontology, Biostratigraphy and Depositional Environments, Latest Cretaceous and Tertiary, Big Bend Area, Texas. Guidebook Field Trip Numbers 1 a, B, and 49th Annual Meeting of the Society of Vertebrate Paleontology, Austin, Texas, 29 October - 1 November 1989. 11-21.
T. sp. nov. (Wel and Williamson, 2000; described by Williamson and Brusatte, 2014)
Early Maastrichtian, Late Cretaceous
Naashoibito Member of Ojo Alamo Formation, New Mexico, US
Material
- (NMMNH P-22566; = UNM FKK-014) tooth (6.8x5.3x2.6 mm) (Williamson and Brusatte, 2014)
(NMMNH P-32746) tooth (Williamson and Brusatte, 2014)
(NMMNH P-32772) tooth (8.4x6x3.3 mm) (Williamson and Brusatte, 2014)
(NMMNH P-32784) tooth (Williamson and Brusatte, 2014)
(NMMNH P-33520) tooth (?x?x3.1 mm) (Williamson and Brusatte, 2014)
(NMMNH P-33521) tooth (3.9x3.3x1.9 mm) (Williamson and Brusatte, 2014)
(NMMNH P-33901) tooth (Williamson and Brusatte, 2014)
(SMP VP-3341) tooth (Jasinski, Sullivan and Lucas, 2011)
Comments- Williamson and Brusatte (2014) found these to be statistically different from Dinosaur Park specimens.
References- Weil and Williamson, 2000. Diverse Maastrichtian terrestrial vertebrate fauna of the Naashoibito Member, Kirtland Formation (San Juan Basin, New Mexico) confirms “Lancian” faunal heterogeneity in western North America. Geological Society of America Abstracts with Programs. 32, A-498.
Williamson, 2001. Dinosaurs from microvertebrate sites in the Upper Cretaceous Fruitland and Kirtland Formations, San Juan Basin, New Mexico. 2001 GSA abstracts.
Jasinski, Sullivan and Lucas, 2011. Taxonomic composition of the Alamo Wash local fauna from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. In Sullivan, Lucas and Spielmann (eds.). Fossil Record 3. New Mexico Museum of Natural History and Science Bulletin. 53, 216-271.
Williamson and Brusatte, 2014. Small theropod teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and their implications for understanding Latest Cretaceous dinosaur evolution. PLoS ONE. 9(4), e93190.
T. sp. indet. (Lambe, 1902)
Late Campanian-Maastrichtian, Late Cretaceous
Judith River or Horseshoe Canyon Formation, Alberta, Canada

(RTMP 81.16.321) anterior dentary tooth (6 mm) (Currie, 1987)
(RTMP 81.20.71) anterior premaxillary tooth (Currie, 1987)
(RTMP 82.20.47) posterior dentary tooth (Currie, 1987)
(RTMP 82.20.299) mid-dentary tooth (Currie, 1987)
(RTMP 84.168.5) maxillary tooth (Currie, 1987)
Late Campanian-Maastrichtian, Late Cretaceous
Judith River or Edmonton Group, Alberta, Canada

(CMN 1266) tooth (Lambe, 1902)
(CMN 1560) astragalus (Zanno et al., 2011)
(CMN 8841) tooth (Sternberg, 1945)
(CMN coll.) five teeth (Sternberg, 1945)
Late Cretaceous
US

(AMNH 21629) tooth (AMNH online)
(YPM 55009) (YPM online)
(YPM 55040) (YPM online)
References- Lambe, 1902. New genera and species from the Belly River Series (mid-Cretaceous). Contributions to Canadian Palaeontology, Geological Survey of Canada. 3, 23-81.
Sternberg, 1945. Pachycephalosauridae proposed for domeheaded dinosaurs, Stegoceras lambei n. sp., described. Journal of Paleontology. 19, 534-538.
Currie, 1987. Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia). Journal of Vertebrate Paleontology. 7, 72-81.
Zanno, Varricchio, O’Connor, Titus and Knell, 2011. A new troodontid theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous western interior basin of North America. PLoS ONE. 6(9), e24487.

Linhevenator Xu, Tan, Sullivan, Han and Xiao, 2011
L. tani Xu, Tan, Sullivan, Han and Xiao, 2011
Campanian, Late Cretaceous
Wulansuhai Formation, Inner Mongolia, China
Holotype
- (LH V0021) (~23 kg adult) incomplete skull (~220 mm), premaxillary tooth, partial surangular, lateral tooth, six incomplete anterior or mid dorsal vertebrae (~29 mm), incomplete scapula (~170 mm), incomplete humerus (~95 mm), incomplete ischium, femur (~240 mm), metatarsal I (~25 mm), incomplete phalanx I-1 (~23 mm), incomplete pedal ungual I (~31 mm), incomplete metatarsal II (~120 mm), incomplete phalanx II-1 (28 mm), incomplete phalanx II-2 (14 mm without heel), incomplete pedal ungual II (~50 mm), metatarsal III (150 mm), phalanx III-1 (~40 mm), incomplete phalanx III-2 (~29 mm), incomplete phalanx III-3 (~25 mm), incomplete pedal ungual III (~31 mm), incomplete metatarsal IV (~145 mm), phalanx IV-1 (~35 mm), phalanx IV-2 (~18 mm), incomplete phalanx IV-3 (~16 mm), incomplete phalanx IV-4 (~17 mm), incomplete pedal ungual IV (~25 mm)
Diagnosis- (after Xu et al., 2011) jugal with lateral flange; surangular crest anteroventrally oriented; presence of medial expansion near distal end of femur; wide longitudinal groove present along distal third of dorsal surface of metatarsal III.
Comments- Discovered in 2009. This was included in a version of Senter's coelurosaur analysis and found to be a derived troodontid in a polytomy with Troodon and Saurornithoides+Zanabazar.
Reference- Xu, Tan, Sullivan, Han and Xiao, 2011. A short-armed troodontid dinosaur from the Upper Cretaceous of Inner Mongolia and its implications for troodontid evolution. PLoS ONE. 6(9), e22916.

Talos Zanno, Varricchio, O’Connor, Titus and Knell, 2011
T. sampsoni Zanno, Varricchio, O’Connor, Titus and Knell, 2011
Late Campanian, Late Cretaceous
Kaiparowitz Formation, Utah, US

Holotype- (UMNH VP 19479) (4 year old subadult) mid dorsal vertebra (22.86 mm), partial mid dorsal centrum, partial posterior dorsal centrum, dorsal fragments, first sacral centrum (19.98 mm), caudal fragment, proximal chevron fragments, radial fragment, ulna (93.4 mm), partial ilium, ilial fragments, incomplete pubes, incomplete ischia, partial femur, partial tibia, partial fibula, astragalus (one fragmentary), calcanea (one fragmentary), metatarsal I, phalanx I-1 (18.7 mm), pedal unguals I (22.89 mm), metatarsals II (158.86 mm), phalanx II-1 (32.29 mm), phalanges II-2 (22.29 mm), pedal ungual II, partial metatarsals III, phalanges III-1 (35.58 mm), phalanges III-2 (25.96 mm), phalanges III-3 (25.68 mm), pedal ungual III, metatarsals IV (175.88 mm), phalanges IV-1, phalanges IV-2, phalanx IV-3 (17.12 mm), phalanges IV-4 (18.02 mm), pedal unguals IV (18.45 mm)
Diagnosis- (after Zanno et al., 2011) acetabular margin of ischium strongly concave dorsally; notch between lateral condyle and ascending process of astragalus in lateral view, poorly developed; intercondylar bridge of astragalus hyperconstricted; proximal groove separating astragalar body and ascending process craniocaudally wide and v-shaped; cranioproximal groove on astragalar condyles absent; astragalar condyles subequal in cranial extent; shaft of metatarsal II markedly compressed (midshaft length-to-transverse width ratio 38.8); metatarsal III distally ginglymoid; pronounced, rounded tab on dorsolateral aspect of metatarsal III proximal to distal condyle; distal corner of lateral collateral ligament pit on metatarsal IV with small protuberance, creating rounded depression between extensor aspects of distal condyles.
Comments- Discovered in 2008 and initially announced by Zanno et al. (2009). This was included in a version of Norell et al.'s (2000) troodontid analysis and found to be at least as derived as Byronosaurus.
References-
Zanno, Varricchio, Titus, Wilkins and Knell, 2009. A new troodontid (Theropoda: Paraves) specimen from the Upper Campanian Kaiparowitz Formation, Southern Utah: Estimating the taxonomic diversity of North American Troodontidae. Journal of Vertebrate Paleontology. 29(3), 205A.
Zanno, Varricchio, O’Connor, Titus and Knell, 2011. A new troodontid theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous western interior basin of North America. PLoS ONE. 6(9), e24487.