Huaxiagnathus

Taxobox

---

name = "Huaxiagnathus"
fossil_range = Early Cretaceous
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Saurischia
subordo = Theropoda
familia = Compsognathidae
genus = "Huaxiagnathus"
genus_authority = Hwang "et al.", 2004
subdivision_ranks = Species
subdivision =
* "H. orientalis" Hwang "et al.", 2004 (type)

"Huaxiagnathus" is a genus of theropod dinosaur from the Lower Cretaceous of China. It was a compsognathid, large for that family at about half a meter longer than "Compsognathus" and larger specimens of "Sinosauropteryx", with the largest specimen about 1.8 meters (6 feet) in length.

The name "Huaxiagnathus" is derived from the Mandarin "Hua Xia", meaning "China", and Greek "gnathus", meaning "jaw."

Description

The holotype (CAGS-IG-02-301, Chinese Academy of Geological Sciences, Beijing) specimen was collected from the Yixian Formation (Jehol Group, Barremian) at Dabangou Village, Sihetun area, near Beipiao City, in western Liaoning Province. The holotype consists of an essentially complete skeleton, lacking only the distal portion of the tail, preserved on five large slabs. A second specimen (NGMC 98-5-003, National Geological Museum of China, Beijing) of "Huaxiagnathus" is known from the Yixian Formation of the Sihetun area, but damage and mistakes made during its preparation rendered it unsuitable as a holotype.

Cladistic analysis indicates that "Huaxiagnathus" is the basalmost known compsognathid, as indicated by its unspecialized forearm.

Hwang "et al." (2004, pp. 14-15) diagnosed this genus as follows: differing from all other known compsognathids in having a very long posterior process of the premaxilla that overlaps the antorbital fossa, a manus equal to the combined lengths of the humerus and radius, large manual unguals I and II which are subequal in length and 167% the length of manual ungual III, a first metacarpal which has a smaller proximal transverse width than the second metacarpal, and the presence of a reduced olecranon process on the ulna.Hwang, S. H., Norrell, M. A., Qiang, J., and Keqin, G. (2004). "A large compsognathid from the Early Cretaceous Yixian Formation of China." "Journal of Systematic Palaeontology", 2(1): 13-30.]

References