SCIURIDS AND ZAPODIDS FROM THE LATE MIOCENE BAHE FORMATION,LANTIAN,SHAANXI

Three forms of Sciuridae,Eutamias lishanensis sp.nov.,Sciurotamias pusillus sp.nov. and Sciurus sp.,and two forms of Zapodidae,Lophocricetus xianensis sp.nov.and Lophocricetus sp. from the lower part of Late Miocene Bahe Formation at Lantian,Shaanxi Province are described. Similarities of the new sciurids in dental morphology to the extant Eutamias sibiricus and Sciurotamias davidianus are indicative of their close affinities,respectively.Sciurotamias pusillus from Lantian re- presents the earliest record of the endemic genus.The new zapodid is also a relatively primitive spe- cies of Lophocricetus known in China,demonstrating more primitive characters than Lophocricetus grabaui Schlosser,1924 commonly known in the Ertemte and Harr Obo faunas of Nei Mongol(Inner Mongolia).Delimitation of the genera Lophocricetus and Heterosminthus,and definition of the species within Lophocricetus are stressed.Both the sciurids and the zapodids argue for an age of Late Miocene for the Babe Formation,corresponding to early Baodean of the Chinese Land Mammal Age system. The presence of these taxa suggests existence of patches of woodland vegetation and temperate climate in an open environment for the Lantian area during the early Late Miocene.