摘要:Nyanzapithecus is a genus of East African Miocene apes, which has been suggested to be an ancestral stock of oreopithecids.A new species of this genus, Nyanzapithecus harrisoni, is described in this article.The description is based on the material discovered from Nachola, a middle Miocene fossil locality (ca.15 m.y.a.) in northern Kenya.N.harrisoni is slightly smaller than the previously known N. pickfordi and N.vancouveringorum, but shares with them such unique dental characters as elongated molar crowns, quite inflated cusps, and restricted occlusal basins and foveae. The presence of the new Nyanzapithecus species in Nachola has expanded the distribution and diversity of this genus, and suggests that oreopithecids may have been a relatively common element in the middle Miocene primate fauna of East Africa.