作者:楠桥直,王元青,李传夔,金 迅
摘要:真三尖齿兽类是了解亚洲白垩纪哺乳动物群演化和转变的重要成员之一。到目前为止沙海组和阜新组(下白垩统上部)已经发现了两种戈壁尖齿兽科以及两种三尖齿兽科的真三尖齿兽类。描述了这些地层产出的真三尖齿兽类的其他材料,包括一新属新种——常氏阜新尖齿兽(Fuxinoconodon changi gen. et sp. nov.)和一枚左下臼齿(鉴定为 ?Gobiconodontidae gen. et sp. indet.)。这种新的真三尖齿兽类被归入戈壁尖齿兽科(Gobiconodontidae), 其特征为:第一下门齿大、门齿和前臼齿的数目变少、臼齿b尖和c尖较大而独立,以及臼齿具有分别属于Gobiconodon第一代或第二代臼齿上独有特征的组合。新材料与同一地区相同层位已经报道的4种真三尖齿兽类表明,虽然科级和属级的多样性似乎已经减少,但亚洲早白垩世晚期仍存在比较多样的真三尖齿兽类。
关键词:辽宁,早白垩世,阜新组,沙海组,哺乳动物,真三尖齿兽类,戈壁尖齿兽科
卷期:第58卷,第1期
New gobiconodontid (Eutriconodonta, Mammalia) from the Lower Cretaceous Shahai and Fuxin formations, Liaoning, China
KUSUHASHI Nao, WANG Yuan-Qing, LI Chuan-Kui, JIN Xun
Abstract Eutriconodontans are one of the key members of mammals to our understanding of the evolution and transition of mammalian fauna in Asia during the Cretaceous. Two gobiconodontid and two triconodontid species have previously been reported from the upper Lower Cretaceous Shahai and Fuxin formations. Here we describe two additional eutriconodontans from the formations, Fuxinoconodon changi gen. et sp. nov. and ?Gobiconodontidae gen. et sp. indet. This new species is attributed to the Gobiconodontidae, characterized by having an enlarged first lower incisor, reduction in the number of incisors and premolariforms, proportionally large cusps b and c being well distant from cusp a on the molariforms, presence of a labial cingulid, and a unique mixed combination of molariform characters seen on either the first or the second, but not both, generations of molariforms in Gobiconodon. Together with the four known species, eutriconodontans remained diverse to some extent in the late Early Cretaceous in Asia, although their family-level and generic level diversity appears to have been already reduced at that time.
Key words Liaoning, Northeast China; Early Cretaceous; Mammalia, Eutriconodonta, Gobiconodontidae