Tuesday, March 6, 2012

[Paleontology • 2006] Akidolestes cifellii • A Cretaceous symmetrodont therian with some monotreme-like postcranial features

 An artist's conception (bottom) depicts Akidolestes, a previously unknown species of mammal that lived alongside dinosaurs some 125 million years ago. A well-preserved fossil of the animal (top) was found in China, which researchers say strengthens the theory that the main mammal groups originated in Asia.
Illustration courtesy Mark A. Klingler/CMNH, photograph courtesy Zhe-Xi Luo

Class Mammalia
Clade Trechnotheria
Family Spalacotheriidae
Akidolestes cifellii gen. et sp. nov.
Holotype. Nanjing Institute of Geology and Palaeontology, Nanjing, China (NIGPAS) 139381A, B (Fig. 1), a skeleton with partial skull and dentition preserved in part and counterpart.

Etymology. Akidolestes: akido- (Greek) for point, for the pointed rostrum of this new mammal; -lestes (Greek), for thief, a common suffix for the name of fossil mammals; cifellii, in honour of Richard L. Cifelli, for his pioneering studies of symmetrodont mammals.
Locality, age and associated fauna. Yixian lacustrine beds at the Dawangzhangzi Locality, Lingyuan, Liaoning, China. The locality is correlated with other localities in Liaoning dated to be 124.6 Myr of the Barremian stage of the Lower Cretaceous, although there is no universal agreement on correlating the Yixian Formation to the European marine stages. Other mammals of this formation include eutriconodontans, multituberculates, symmetrodonts, metatherians and eutherians.

Li, G. and Z.-X. Luo. 2006. A Cretaceous symmetrodont therian with some monotreme-like postcranial features. Nature, 439:195-200. 

Extinct Species of "Mosaic" Mammal Found in China: 
125 Million-Year-Old Insect-Eating Mammal Fossil Found in China: http://www.greendiary.com/entry/125-million-year-old-insect-eating-mammal-fossil-found-in-china