Revision to Kowalskia from the Houhecun Fauna and a New Discovery of Tscherskia (Cricetidae, Rodentia) from the Youhe Fauna of Weinan, Shaanxi Province, China

다국어 초록 (Multilingual Abstract)

The fossil hamster (an isolated m1) from the early Early Pleistocene Houhecun fauna found in Dali, Weinan, Shaanxi, China, originally identified as Kowalskia dalinica, is reexamined. Its unique characters, including a high crown, very small degree of division of the anteroconid and relatively large size, is taken as evidence of its attribution to the genus Sinocricetus, instead of Kowalskia (junior synonym of Neocricetodon) suggested by the original author. Therefore, the specific name of the species established based on this m1 should be changed to S. dalinicus (Wang, 1988). S. dalinicus probably has a relatively close affinity with S. major Li, 2010, but there are still some obvious differences of characters between them. The discovery of S. dalinicus in the Houhecun fauna confirms that the genus indeed survived into the Pleistocene. A broken hamster mandible, which was found in Weinan, Shaanxi, China and belongs to the late Pliocene Youhe fauna, is also described here and identified as Tscherskia sp. This specimen represents the earliest Tscherskia in Asia so far, but fails to refute the hypothesis that the genus originated in Europe during the early Pliocene.