A new nonmammalian eucynodont (Synapsida, Therapsida) from the Triassic of northern Gansu Province, China, and its biostratigraphic and biogeographic implications

Title Variants

Alternative: New nonmammalian eucynodont

Related Titles

Series: American Museum novitates, no. 3685

By

Gao, Keqin, 1955-
Fox, Richard C.
Zhou, Chang-Fu.
Li, Da-Qing, paleontologist.

Type

Book

Material

Published material

Publication info

New York, NY, American Museum of Natural History, c2010

Notes

Caption title.

"June 25, 2010."

A new trirachodontid eucynodont, Beishanodon youngi, is named and described based on a well-preserved skull from Triassic lacustrine deposits exposed in the Beishan Hills, northern Gansu Province, China. The new discovery documents the second record of trirachodontid eucynodonts known from China, along with Sinognathus gracilis from the Middle Triassic Ermaying Formation exposed in Shanxi Province. Cladistic analysis supports the placement of the new taxon as the sister group of Sinognathus, and the two together can be classified in Sinognathinae, a new subfamily differentiated from other trirachodontids by possession of several derived character states, including extremely short snout and strongly expanded temporal region. In addition, the stratigraphic and biogeographic significance of the new discovery are discussed. Because trirachodontids have a restricted stratigraphic range in the Triassic, as best documented by the Cynognathus Assemblage Zone of South Africa, discovery of the new fossil of this group from northern Gansu Province in China provides definitive evidence for a Triassic age of the fossil-bearing beds exposed in the Beishan Hills; moreover, the fossil beds are assessed as early Triassic in age based on the evidence from the entire vertebrate fauna.

Subjects

Anatomy , Beishanodon youngi , China , Gansu Sheng , Paleontology , Phylogeny , Reptiles, Fossil , Skull , Stratigraphic correlation , Therapsida , Triassic

Call Number

QL1 .A436 no.3685 2010

Language

English

Identifiers

OCLC: 645099046