Belongs within: Archosauriformes.
Contains: Stagonolepidae, Crocodylomorpha.
The Pseudosuchia are a clade of reptiles including the crocodilians and a number of related fossil taxa once classified as ‘thecodontians’ such as the aetosaurs, ornithosuchids and ‘rauisuchians’. Higher relationships within the clade have differed between analyses though most recent authors have agreed that the ‘rauisuchians’ (Rauisuchidae, Prestosuchidae and Poposauridae) do not form a single clade. Indeed, an analysis of the archosauriforms by Nesbitt et al. (2017) did not even recover monophyly for the individual rauisuchian families.
The Ornithosuchidae are gracile reptiles with slender hind limbs and long hind toes that may have been at least partially bipedal (Romer 1972b).
Synapomorphies (Benton & Clark 1988): Septomaxilla absent; lower temporal fenestra reduced in size, triangular with a dorsal point, quadratojugal sloping forward towards postorbital; axial diapophysis reduced or absent; pubo-ischiadic plate absent, pubis and ischium long and narrow, pubis expanding distally into broad forward-facing plate; long distal process of pubis bent down into subvertical orientation; pubis longer than ischium; proximal head of femur turned inwards at about 45°; fully developed crocodile-normal tarsus, capable of rotation of 60–70°; digit V in foot reduced in length, shorter than digit I.
<==Pseudosuchia (see below for synonymy)NS09
|--Nundasuchus songeaensisNB17
`--+--OrnithosuchidaeB04
| |--Venaticosuchus rusconii Bonaparte 1971B93
| |--Parringtonia gracilisR72b, NB17
| |--Riojasuchus Bonaparte 1969IN07, R72b
| | `--R. tenuiceps Bonaparte 1969B93
| `--Ornithosuchus Newton 1894NB17, GQ01 [incl. DasygnathoidesR72b]
| |--*O. longidens (Huxley 1877) [=Dasygnathus longidens; incl. O. woodwardi Newton 1894]GQ01
| `--O. rusconiiP88
`--+--+--StagonolepidaeNB17
| `--Revueltosaurus Hunt 1989NS09, PI05 [incl. Galtonia Hunt & Lucas 1994 non Decaisne 1880 (ICBN)NWW04]
| |--R. callenderi Hunt 1989PI05
| |--‘Thecodontosaurus’ gibbidens Cope 1878NWW04 [=*Galtonia gibbidensNWW04, FR24]
| |--R. hunti Heckert 2002PI05 [=Krzyzanowskisaurus huntiFR24]
| `--‘Pekinosaurus’ olseni Hunt & Lucas 1994 (n. d.)FR24, NWW04
`--+--Kollamasuchus gonzalezdiaziNB17
`--+--+--TurfanosuchusNB17
| | |--T. dabanensis Young 1973B93
| | `--T. shageduensis Wu 1982B93
| `--+--Yonghesuchus sangbiensisNB17
| `--Gracilisuchus Romer 1972NB17, D07
| `--*G. stipanicicorum Romer 1972R72a
`--+--Ticinosuchus Krebs 1965NB17, D07 (see below for synonymy)
| `--T. ferox Krebs 1965G00
`--+--+--Qianosuchus mixtusNB17
| `--+--+--Xilousuchus sapingensisNB17
| | `--Arizonasaurus Welles 1947NB17, G00
| | `--A. babbittiNS09
| `--+--Poposaurus gracilis Mehl 1915NB17, G00
| `--+--CtenosauriscidaeB93
| | |--Ctenosauriscus koeneni (Huene 1902)B93
| | `--Lotosaurus Zhang 1975NB17, D07
| | `--L. adentus Zhang 1975G00
| `--+--Sillosuchus longicervix Alcober & Parrish 1997NB17, G00
| `--+--Effigia okeeffeaeNB17
| `--Shuvosaurus Chatterjee 1993NB17, D07
| `--S. inexpectatusG00
`--+--Prestosuchus chiniquensis Huene 1942NB17, G00 [incl. P. loricatus Huene 1942G00]
`--+--Saurosuchus Reig 1959NB17, R72b
| `--S. galilei Reig 1959G00
`--+--Batrachotomus kupferzellensis Gower 1999NB17, G00
`--+--Fasolasuchus tenax Bonaparte 1978NB17, G00
`--+--+--TrialestesBC88
| |--CrocodylomorphaNB17
| `--Erpetosuchus Newton 1894CX04, D07 [=HerpetosuchusR72b]
| `--E. grantiD07
`--+--Rauisuchus tiradentes Huene 1942NB17, G00
`--+--Polonosuchus silesiacusNB17
`--PostosuchusNB17
|--P. alisonaeNB17
`--P. kirkpatricki Chatterjee 1985G00
Pseudosuchia incertae sedis:
Belodon [Belodontia]C77
`--B. kapffiM96
StrigosuchusR72b
Wangisuchus Young 1974G00
`--W. tzeyii Young 1964B93
Vytshegdosuchus zheshartensis Sennikov 1988G00
Energosuchus garjainovi Ochev 1986G00
Dongusia Huene 1940G00
PallisteriaR72b
TsylmosuchusG00
|--T. donensis Sennikov 1990G00
|--T. jakovlevi Sennikov 1990G00
`--T. samariensis Sennikov 1990G00
EpiscoposaurusG00
DolichobrachiumG00
ChirotheriumG00
VjushkovisauriniG00
|--Vjushkovisaurus berdjanensis Ochev 1982G00
|--Jaikosuchus magnus Sennikov 1990G00
|--Jushatyria vjushkovi Sennikov in Kalandadze & Sennikov 1985G00
`--Youngosuchus Sennikov in Kalandadze & Sennikov 1985G00
`--*Y. sinensis (Young 1973) [=Vjushkovia sinensis]G00
StagonosuchusG00
|--S. major (Haughton 1932)B93
`--S. nyassicus Huene 1938G00
Zanclodon Plieninger 1846 [Zanclodontidae]G00
Tikisuchus romeri Chatterjee & Majumdar 1987G00
Luperosuchus fractus Romer 1971G00
Hoplitosuchus raui Huene 1942G00
Procerosuchus Huene 1944G00, R72b
`--P. celer Huene 1942G00
Heptasuchus Dawley, Zawiskie & Cosgriff 1979DZC79
`--*H. clarki Dawley, Zawiskie & Cosgriff 1979DZC79
Lythrosuchus langstoni Long & Murray 1995G00
Bromsgroveia walkeri Galton 1985G00
Teratosaurus suevicus v. Meyer 1861G00
Chatterjeea [Chatterjeeidae]G00
`--C. elegans Long & Murray 1995G00
Nomen nudum: Mandasuchus tanyauchen Charig in Appleby et al. 1967G00
Pseudosuchia [Crocodylotarsi, Dromaeosuchia, Poposauridae, Prestosuchidae, Procrocodylomorpha, Rauisuchia, Rauisuchidae, Rauisuchiformes, Rauisuchinae, Rauisuchini, Suchia]NS09
Ticinosuchus Krebs 1965NB17, D07 [incl. Mandasuchus Charig in Appleby et al. 1967 (n. n.)G00; Ticinosuchinae]
*Type species of generic name indicated
References
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[B04] Benton, M. J. 2004. Origin and relationships of Dinosauria. In: Weishampel, D. B., P. Dodson & H. Osmólska (eds) The Dinosauria 2nd ed. pp. 7–19. University of California Press: Berkeley.
[BC88] Benton, M. J., & J. M. Clark. 1988. Archosaur phylogeny and the relationships of the Crocodylia. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 1. Amphibians, Reptiles, Birds pp. 295–338. Clarendon Press: Oxford.
[CX04] Clark, J. M., X. Xu, C. A. Forster & Y. Wang. 2004. A Middle Jurassic ‘sphenosuchian’ from China and the origin of the crocodylian skull. Nature 430: 1021–1024.
[C77] Cope, E. D. 1877. Report upon the extinct Vertebrata obtained in New Mexico by parties of the expedition of 1874. Geographical Surveys West of the One Hundredth Meridian 4 (2): i–iv, 1–370.
[DZC79] Dawley, R. M., J. M. Zawiskie & J. W. Cosgriff. 1979. A rauisuchid thecodont from the Upper Triassic Popo Agie Formation of Wyoming. Journal of Paleontology 53 (6): 1428–1431.
[D07] Dixon, D. 2007. The Complete Illustrated Encyclopedia of Dinosaurs & Prehistoric Creatures. Hermes House: London.
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[GQ01] Gauthier, J., & K. de Queiroz. 2001. Feathered dinosaurs, flying dinosaurs, crown dinosaurs, and the name “Aves”. In: Gauthier, J., & L. F. Gall (eds) New Perspectives on the Origin and Early Evolution of Birds: Proceedings of the International Symposium in Honor of John H. Ostrom pp. 7–41. Peabody Museum of Natural History, Yale University: New Haven.
[G00] Gower, D. J. 2000. Rauisuchian archosaurs (Reptilia, Diapsida): an overview. Neues Jahrbuch für Geologie und Paläontologie—Abhandlungen 218 (3): 447–488.
[IN07] Irmis, R. B., S. J. Nesbitt, K. Padian, N. D. Smith, A. H. Turner, D. Woody & A. Downs. 2007. A Late Triassic dinosauromorph assemblage from New Mexico and the rise of dinosaurs. Science 317: 358–361.
[M96] Marsh, O. C. 1896. The Dinosaurs of North America: Washington.
[NB17] Nesbitt, S. J., R. J. Butler, M. D. Ezcurra, P. M. Barrett, M. R. Stocker, K. D. Angielczyk, R. M. H. Smith, C. A. Sidor, G. Niedźwiedzki, A. G. Sennikov & A. J. Charig. 2017. The earliest bird-line archosaurs and the assembly of the dinosaur body plan. Nature 544: 484–487.
[NS09] Nesbitt, S. J., N. D. Smith, R. B. Irmis, A. H. Turner, A. Downs & M. A. Norell. 2009. A complete skeleton of a Late Triassic saurischian and the early evolution of dinosaurs. Science 326: 1530–1533.
[NWW04] Norman, D. B., L. M. Witmer & D. B. Weishampel. 2004. Basal Ornithischia. In: Weishampel, D. B., P. Dodson & H. Osmólska (eds) The Dinosauria 2nd ed. pp. 325–334. University of California Press: Berkeley.
[PI05] Parker, W. G., R. B. Irmis, S. J. Nesbitt, J. W. Martz & L. S. Browne. 2005. The Late Triassic pseudosuchian Revueltosaurus callenderi and its implications for the diversity of early ornithischian dinosaurs. Proceedings of the Royal Society of London Series B—Biological Sciences 272: 963–969.
[P88] Paul, G. S. 1988. Predatory Dinosaurs of the World: A Complete Illustrated Guide. Simon & Schuster: New York.
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