A new genus and species,Nakalimys lavocati, is described from the Nakali locality, Kenya, of about 10 Ma. This muroid rodent is assigned to the Rhizomyidae and is most similar toKanisamys indicusfrom the Miocene of Pakistan, with which it was originally considered congeneric.Nakalimys, with other rodents and vertebrates, points to interchange between eastern Africa and southern Asia earlier than 10 Ma, before a more recent period of strong faunal similarity at about the beginning of the Pliocene.Nakalimyspossesses many primitive characters, but was not directly ancestral to fossil and extantTachyoryctesof Africa.