Blancan camelids from San Miguel de Allende, Guanajuato, central México

During the Pliocene, the diversification of the tribes Lamini and Camelini of the Family Camelidae took place in most of North America, but at present in Mexico the systematics of Pliocene Camelidae are poorly known. Fossil material described in this paper was recovered from Blancan I and Blancan III age floodplain and point bar deposits of the San Miguel de Allende basin, Guanajuato state, central Mexico, which approximately spans a time frame from 4.7 to 3.0 Ma. The identified taxa include the laminesHemiauchenia blancoensis(Meade) 1945,Hemiauchenia gracilisMeachen, 2005,Blancocamelus meadeiDalquest, 1975 andCamelopssp., while the camelines are represented byMegatylopussp. The records ofH. gracilisandB. meadeiin the Pliocene of central Mexico are the oldest in North America. Previous studies of the probable feeding strategies of these taxa indicate that they were browsers or browser-like intermediate feeders and just one was an intermediate feeder. The records of these species in the Early Blancan of Guanajuato extend their geographic distribution from the southern USA to central Mexico.