继1990年王伴月和李春田记述了发现在吉林桦甸中始新世的争胜鼠(Zelomys)之后,近年又在山西垣曲、河南卢氏、江苏溧阳等地的中始新世到晚始新世(Irdinmanhan-late Sharamurunian or Ergilian) 的5个地点中陆续发现了一些与争胜鼠相近的新材料.经研究后,将所有材料归诸于创建的一新科:争胜鼠科(Zelomyidae fam. nov.). 它包括了争胜鼠及本文新记述的安氏鼠(Andersomys gen. nov.)、耗子(Haozi gen. nov.)和苏鼠(Suomys gen. nov.)共4属6种.新科的特征是:始啮型头骨-松鼠型下颌;门齿釉质层散系;颊齿具有发育的次尖和下次脊,后期种类上颊齿的外侧齿尖的唇侧发展成平凹到新月形.新科的系统关系不很清楚,尽管与始鼠科(Eomyidae)有某些相似之处,但它更可能是独立发展的一个支系.争胜鼠属化石分布较广,在我国吉林、江苏和山西的中、晚始新世地层中都有发现,它的特征是下颊齿p4-m2宽度逐渐增大,p4-m3具下前边尖,并与短的下原尖前臂相接.属中除属型种--东方争胜鼠(Z. orientalis Wang et Li)外,还建立了一个约翰争胜鼠新种(Z. joannes sp. nov.), 一约翰争胜鼠相似种(Z. cf. Z. joannes).同时认为Z. gracilis Wang et Li,1990是Z. orientalis的同物异名.约翰种与属型种的区别在于个体稍大和下臼齿上缺少自下外脊伸出的附脊.安氏鼠属化石发现在山西中始新世晚期及有可能是晚始新世地层中,其特征是P4 和p4分别大于M1和m1;P4前尖和后尖及M1后尖唇侧平;与争胜鼠属不同在于前臼齿和臼齿的大小比例和上颊齿具平的唇侧尖.安氏鼠包括两种:老文种(A. laoweni sp. nov.)和南堡头种(A.austrarx sp. nov.).两种的不同在于后者个体稍大,P4唇侧齿带较发育和p4前缘更显圆滑. 耗子属仅有一种,简单耗子(H. simplex sp. nov.),与科中其他属的不同在于颊齿齿尖较呈丘形,P4和M1大小接近,上颊齿的前附尖和后附尖很发育,P4三角凹宽于跟凹.该属化石仅发现在河南中始新世晚期地层中.苏鼠属也只有新月苏鼠(S. selenis sp. nov.)一种,发现在江苏中始新世晚期到晚始新世地层中.该属的特点是P4比其他上颊齿大,具强的前齿带和唇侧齿带;P4-M2的前尖和后尖及M3的前尖唇侧凹平,且向前、后延长,形成W形外壁,中附尖明显;下颊齿的唇侧尖也呈W形结构,使牙齿为新月形式样,这是与科中其他属明显不同的特征.文中还对含化石地层时代问题做了评述.%Six Eocene localities in eastern China, ranging geographically from Jilin to Jiangsu provinces and in age from Irdinmanhan to late Sharamurunian or Ergilian, have yielded four genera (Haozi, Suomys, and Andersomys named as new here and Zelomys) assigned to the new rodent family Zelomyidae. The family is characterized by a primitive protrogomorphous-sciurognathous zygomasseteric structure and pauciserial incisor enamel, but the cheek teeth are precocious in development of hypocone and hypolophid. Later members of the family exhibit a development of buccal flattening to selenodonty of the cusps of the cheek teeth. Relationships of the new family are unclear, although some dental similarities suggest affinities with the Eomyidae. On the other hand, differences from eomyids may suggest that the zelomyids are an independently derived Asian Eocene family.
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