Ornithosuchidae Huene, 1907

Nesbitt, Sterling J., 2011, The Early Evolution Of Archosaurs: Relationships And The Origin Of Major Clades, Bulletin of the American Museum of Natural History 2011 (352), pp. 1-292 : 194-195

Ornithosuchidae Huene, 1907 –1908

ORIGINAL DEFINITION: Ornithosuchus , Riojasuchus , Venaticosuchus , and all descendants of their common ancestor ( Sereno, 1991a).

REVISED DEFINITION: Stem: The most inclusive clade containing Ornithosuchus longidens Huxley, 1877 , but not Rutiodon carolinensis Emmons, 1856 , Aetosaurus ferra-

tus Fraas, 1877, Rauisuchus tiradentes Huene, 1942 , Prestosuchus chiniquensis Huene, 1942 , Crocodylus niloticus Laurenti, 1768 , or Passer domesticus Linnaeus, 1758 (modified from Sereno, 2005).

TEMPORAL RANGE: Late Triassic (Carnian, Ornithosuchus longidens Huxley, 1877 , to mid-Norian–?Rhaetian, Riojasuchus tenuisceps Bonaparte, 1967 ).

SUPPORT: The monophyly of Ornithosuchidae has never been contested. However, Sereno (1991a) is the only person to include both Ornithosuchus and Riojasuchus as separate terminal taxa.

(1) Three premaxillary teeth (6-0). (2) Downturned premaxilla (8-1)*. (3) Two-tooth diastema between the posterior premaxillary teeth and the anterior maxillary teeth between the maxilla and the premaxilla (13-1)*. (4) Nasal-prefrontal contact absent (33-1)*. (5) Posterolateral (5 occipital) process of the parietals anteriorly inclined greater than 45 ° (62-1). (6) Palatine-pterygoid fenestra present (85-1)*. (7) Orbit with distinct ventral point surrounded by V-shaped dorsal processes of jugal (142-2)*. (8) Dentary-splenial mandibular symphysis present along one-third of lower jaw (160-1). (9) Cervical vertebrae, middle portion of the ventral keel extends ventral to the centrum rims (190-1)*. (10) Pubis 70% or more of femoral length (278-1). (11) Anterior trochanter (5 M. iliofemoralis cranialis insertion) present and forms a steep margin with the shaft but is completely connected to the shaft (308-1)*. (12) Astragalus-calcaneum, ventral articular surface concavoconvex with concavity on astragalus (368-2)*. (13) Metatarsal V ‘‘hooked,’’ proximal end absent (398-1).

Other possible synapomorphies: AC- CTRAN: Lateral surface of the exoccipital without subvertical crest (5 metotic strut) (114-0); primordial trunk vertebrae incorporated into the sacrum, with their ribs/ transverse processes articulating with the pelvis (205-1); accessory laminar process on anterior face of neural spine of the midcaudal vertebrae present (210-1); gap at the midline between the distal ends of the ischia (292-1); attachment site for the M. iliofibularis near the midpoint between the proximal and distal ends (340-1). DELTRAN: Diapophyses and parapophyses of the middle dorsal vertebrae

expand laterally where both diapophyses and parapophyses originate on a transverse process (199-1); attachment site for the M. iliofibularis of the fibula knob shaped or tablike, robust (339-1).