中国四川省塩井溝産のStegodon orientalis Owen, 1870 (Stegodontidae, P 「ObOSCidea 」の頭蓋について( 予報

Abstract

A cursorial description is given of the cranial morphology of Stegodon orientalis Owen, 1870, based on materials collected by W. Granger during 1920-1921 from Yanjingou, Sichuan, China. The cranial vault of S. orientalis shows enigmatic autapomorphies such as loss of the crista nuchae, a pair of prominent domes on the vertex and a shallow groove on the forehead. Beside these enigmatic characteristics, the cranial morphology, the forehead in particular, closely resembles that of S. trigonocephalus and S. ganesa, suggesting a sister-group relationship for S. orientalis and the S. trigonocephalus group (sensu Saegusa, in print)