DINOSAURIA OWEN, 1842 SENSU PADIAN AND

Marsh, Adam D. & Parker, William G., 2020, New dinosauromorph specimens from Petrified Forest National Park and a global biostratigraphic review of Triassic dinosauromorph body fossils, PaleoBios 37, pp. 1-56 : 13

DINOSAURIA OWEN, 1842 SENSU PADIAN AND MAY, 1993

FIG. 6A–H

Referred specimens and localities — PEFO 44475 ( Fig. 6A–D), proximal ends of left and right femora, PFV 376: Scour Sandstone, PFM; PEFO 34583 ( Fig. 6E, F), proximal end of left femur, PFV 332: Chinde Valley Pin- nacle, PFM; PEFO 34863 ( Fig. 6G, H), proximal end of left femur, PFV 215: Zuni Well Mound, PFM.

Description and rationale for assignment —These proximal ends of femora are highly fragmentary and weathered; each of them is broken proximal to the fourth trochanter. Each preserves a mound-like anterior trochanter that remains attached to the shaft proximally (Nesbitt 2011:308-1) ( Fig. 6D), which is a feature present in Dinosauriformes, e.g., Marasuchus lilloensis (PVL

3871, Sereno and Arcucci 1994: fig. 8b), Asilisaurus kongwe (NMT RB159, Nesbitt et al. 2019: fig. 42d), and Buriolestes schultzi (ULBRA-PVT280, Cabreira et al. 2016: fig. 1n). Unlike the smooth transition between the ventromedial margin of the femoral head and the shaft (Nesbitt 2011:304-0) found in early dinosauromorphs, e.g., Lagerpeton chanarensis Romer (1971, PVL 4619) (Nesbitt et al. 2009b: fig. 3a), and Dromomeron romeri (GR 218, Nesbitt et al. 2009b: fig. 1a) and the ventral notch (Nesbitt 2011:304-1) present on silesaurid femora (see above), these femora exhibit a concave emargination ventral to the femoral head (Nesbitt 2011:304-2) ( Fig. 6H), which is apomorphic for dinosaurs, e.g., Eocursor parvus (SAM-PK-K8025, Butler 2009: fig. 15d), Eodromaeus murphi Martínez et al. (2011, PVSJ 562: fig. 2k), and Herrerasaurus ischigualastensis (PVSJ 373, Novas 1993: fig. 7c). Thus, we assign these fragmentary proximal ends of femora to Dinosauria .