内蒙古四子王旗大庙中新世的真角鹿一新种(英文)

描述了内蒙古四子王旗大庙中中新世化石地点(DM01)产出的真角鹿一新种:高枝真角鹿Euprox altus sp.nov.。新种具真正的角节,角节之上一定高度的两个分枝,长的角柄;牙齿低冠,上臼齿的前附尖和中附尖发育,新棱和齿带存在;p4的下后尖发育,下次凹存在;下臼齿具古鹿褶。这些特征可作为其归入真角鹿属Euprox的依据。Euprox altus最主要的特征是其分叉起始位置比属内其他种的高。分叉起始位置的标志是角基的突然变宽,它不同于分叉的位置,可作为一个新的鉴定特征。角冠表面纵向分布不均的沟棱、更低冠的牙齿、P4原尖后棱上的脊、p4不明显的下前凹和不是很发育的下三角凹、下臼齿上发育较弱的古鹿褶等特征都是新种区别于属内其他种的重要特征。Euprox altus所指示的可能是温暖湿润的生活环境,与大庙现在干旱、恶劣的景象截然不同。

A NEW SPECIES OF EUPROX ( CERVIDAE, MAMMALIA) FROM THE MIDDLE MIOCENE OF DAMIAO, NEI MONGOL, CHINA

A new species of cervid,Euprox altus,from the Middle Miocene fossil locality of Damiao,Siziwangqi,Nei Mongol,is described and studied in detail.It is assigned to Euprox based on its true burrs,bifurcation above the burr,long pedicles,brachyodont cheek teeth,developed parastyle and mesostyle,neocrista and cingulum on each upper molar,developed metaconid and hypoflexid on p4 and Palaeomeryx folds on lower molars.The diagnostic character of E.altus is that the bifurcation begins at a higher position than in other species.The beginning of the bifurcation is indicated by an abrupt widening of the antler base.This position can be used as a new distinguishing feature,distinct from the overall position of bifurcation.The uneven longitudinal grooves,more brachyodont teeth,fold on the P4 postprotocrista,almost invisible paraflexid and small trigonid basin on p4,and weak Palaeomeryx fold on the lower molars further differentiate the new species from other Euprox species.The presence of E.altus may indicate a warm and humid environment during the latest Middle Miocene in the Damiao area,in sharp contrast to the current dry and harsh environment.