Early Eocene deposits in the County Mine locality of the Wutu Basin, Shandong Province, People's Republic of China, have yielded a varied mammalian fauna that includes three families of rodents. The family Alagomyidae, previously named for taxa from Mongolia, is represented by a new species. The Ctenodactyloidea, becoming well known in eastern Asia, are represented by a new genus and species. The first occurrence of the family Paramyidae in the Early Eocene of Asia is recorded by a new genus and two new species.
Two new genera and species of carpolestid plesiadapoids are described from early Eocene coal beds of the Wutu Formation, Wutu Basin, Shandong Province, People's Republic China. Chronolestes simul, n. gen. and sp., possesses a reduced P-3 and hypertrophied P-4 as do all carpolestids, but contrasts with other members of this family in lacking a bladelike, polycuspidate P-4. P3-4 of Chronolestes are structurally simpler, and almost certainly more primitive, than those of any other plesiadapoid. Chronolestes is interpreted as the sister group of all other carpolestids and forms the basis for the new, monotypic subfamily Chronolestinae. Carpocristes oriens, n. gen. and sp., is a dentally derived carpolestine characterized by triple median crests on P3-4 and an S-shaped blade on P-4. The closely related North American species ''Carpodaptes'' hobackensis and ''Carpodaptes'' cygneus are transferred here to the new genus Carpocristes. Relationships among species of Carpocristes are reconstructed as (C. cygneus (C. hobackensis, C. oriens)). Potential dental synapomorphies for Plesiadapoidea, including Plesiadapidae, Saxonellidae, and Carpolestidae, are identified for the first time. Within Plesiadapoidea, available evidence weakly supports the monophyly of a Plesiadapidae + Saxonellidae clade. Altanius orlovi from the early Eocene of Mongolia is unlikely to be either a plesiadapoid or a basal carpolestid. The fossil record of North American and Asian Carpolestidae suggests at least two episodes of trans-Beringian dispersal for members of this clade during the Paleocene. The timing of these dispersal episodes is weakly constrained, but middle Torrejonian (Chronolestes dade) and latest Tiffanian or earliest Clarkforkian (Carpocristes clade) dispersal events conform with inferences regarding trans-Beringian dispersal of other groups of Paleocene mammals. The recent hypothesis that competitive exclusion by rodents may have been a causal factor underlying carpolestid extinction in North America is called into question by the co-occurrence of two carpolestids and ctenodactyloid, alagomyid, and paramyid rodents at Wutu, together with the high probability that both carpolestids and rodents coexisted in Asia through much of the Paleocene.