Shenzhousaurus orientalis

JI, QIANG, NORELL, MARK A., MAKOVICKY, PETER J., GAO, KE-QIN, JI, SHU'AN & YUAN, CHONGXI, 2003, An Early Ostrich Dinosaur and Implications for Ornithomimosaur Phylogeny, American Museum Novitates 3420 (1), pp. 1-20 : 2

Shenzhousaurus orientalis , new taxon

TYPE SPECIMEN: NGMC ( National Geological Museum of China) 97­4­002 .

MATERIAL: A partial skeleton preserved on a sandstone block in a death pose with its

head above the torso. The distal hindlimbs, distal tail, and the forelimbs (except for part of the right hand) and the pectoral girdle are missing. The head is crushed, exposing the left side obliquely.

ETYMOLOGY: Shenzhou is the ancient name of China, orientalis refers to the east.

TYPE LOCALITY: Sihetun fossil site, Beipiao, Western Liaoning, China ( fig. 3 ) .

GEOLOGICAL OCCURRENCE: The holotype comes from the lowermost, fluvial part of the Early Cretaceous Yixian Formation. These rocks are older than 128 mybp and younger than 139 mybp ( Swisher et al., 2002); older dates have been reported ( Lo et al., 1999).

DIAGNOSIS: an ornithomimosaur distinguishable from all others except Harpymimus in having teeth restricted to the anterior dentary. Shenzhousaurus orientalis shows primitive characters not found in advanced ornithomimosaurs, like a straight ischium and a postacetabular process that is gently curved rather than truncated. Shenzhousaurus orientalis is distinguishable from Pelecanimimus by the tooth distribution pattern and the primitive configuration of the hand where digit I is shorter than digits II and III.

Figures

Fig. 3. The fossil locality.