A NEW TRITYLODONTID FROM THE UPPER JURASSIC SHISHUGOU FORMATION OF THE JUNGGAR BASIN (XINJIANG, NW CHINA)
Michael W. Maisch, Andreas T. Matzke, and Ge Sun, Journal of Vertebrate Paleontology, 2004, 24(3):649–656
A new tritylodontid cynodont, Bienotheroides ultimus sp. nov., is described from the Upper Jurassic Shishugou Formation of Jiangjunmiao in the northeastern Junggar Basin of Xinjiang (NW China). The type consists of a partial skeleton, including teeth, a partial skull, and a considerable portion of the postcranium. It is identifiable as Bienotheroides because Of the structure of the upper molars and the characteristically deep zygomatic arch. It is distinguished front Bienotheroides zigongensis front the Middle Jurassic of the Junggar Basin particularly by characters of the forelimb, including a humerus that shows little torsion of the proximal and distal ends. Bienotheroides ultimus is the last of the Chinese tritylodontids known so far, and apart from Xenocretosuchus from the Lower Cretaceous of Russia and an unnamed form from the Lower Cretaceous of Japan, it is the last non-mammalian therapsid known in the entire fossil record.