Abstract: A new species of Eomyodon, E.dangheensis，is described based on specimens discovered from the late Oligocene in the Danghe area, Gansu, China. Its main features are: cheek teeth brachydont; lower cheek teeth with posterosinusid; p4 with distinct protostylid and without anteroconid or anterolophid; ml/2 with free anterolophid, long mesolophid, lingually open synclinids, well-developed synclinid IV; ml/2 with posterior crest of paracone, long and straight mesoloph, long and closed syncline II, and long sinus. Pseudotheridomys asiazicus Wang and Emry, 1990, is transferred to Eomyodon (E. asiaticus) because its cheek teeth, except V 9575, are more similar to Eomyodon rather than to Pseudotheridomys. V9575 is tentatively retained as Pseudotheridomys sp. It is evident that Eomyodon known in Europe occurred and diversified in Asia in late Oligocene, but has not ever been reported from North America. Thus, the exchange of Eomyodon took only place between Asia and Europe in late Oligocene.

摘要： 始鼠科（Eomyidae）是一类已绝灭的小型的鼠类，在古近纪和新近纪时广布全北区，以北美（中始新世一晚中新世）和欧洲（早渐新世一晚上新世）发现的化石较丰富。过去在亚洲发现的始鼠化石极少。亚洲的第一个始鼠化石是1982年才发现的（郑绍华等，1982）。 20世纪年代以来，在亚洲陆续发现了一些始鼠化石，表明从中始新世到上新世时在亚洲已有始鼠生存过 (Wang and Emry, 1990；Qiu，1994，1996；Tomida and Setoguchi，1994；Emry al.，1997；王伴月等，19