Phylogeny and biogeography of the genus Ansomys Qiu, 1987 (Mammalia:Rodentia:Aplodontidae) and description of a new species from the Barstovian (Mid-Miocene) of Montana
Phylogeny and biogeography of the genus Ansomys Qiu, 1987 (Mammalia:Rodentia:Aplodontidae) and description of a new species from the Barstovian (Mid-Miocene) of Montana
复制标题
DOI：
10.1666/0022-3360(2004)078
复制
发表时间：
2004-07-01
影响因子：
1.4
通讯作者：
Hopkins, SSB
中科院分区：
文献类型：
--
作者：
Hopkins, SSB
从蒙大拿州赫本梅萨发现的新的亚倍齿象材料，刺激了对安索鼠的重新研究，安索鼠是一种以前只在亚洲发现的亚倍齿象属。对 Ansomys 已知物种的分支分析，以及来自 Hepburn's Mesa 和其他一些形态相似物种的新材料，促进了该属生物地理学历史的重建。一种新物种。描述了来自蒙大拿州 Barstovian 的 A. hepburnensis，另外两个物种 A. nexodens 和 A. Descendens 分别被放置在 Ansomys 中，而不是分别放置在 Pseudallomys 和 Plesispermophilus 中。这三个物种的加入扩大了其在中新世中期整个全北区的分布。地层范围与物种之间的系统发育关系相结合表明早在渐新世晚期就有这种广泛的分布，这在倍齿象属中是独一无二的。 Ansomys 的分布、稀有性、异常小的尺寸和复杂的尖头形态表明该分支成员具有非常特殊的生态学。
New aplodontid material recovered from Hepburn's Mesa, Montana, stimulated reexamination of Ansomys, a genus of aplodontid previously known only from Asia. A cladistic analysis of the known species of Ansomys, as well as new material from Hepburn's Mesa and a few other morphologically similar species, prompted reconstruction of the biogeographic history of the genus. One new species. A. hepburnensis, from the Barstovian of Montana, is described, and two other species, A. nexodens and A. descendens, are placed in Ansomys rather than in Pseudallomys and Plesispermophilus, respectively. Addition of these three species to Ansomys extends its distribution throughout the Holarctic in the mid-Miocene. Stratigraphic ranges combined with phylogenetic relationships between species suggest this wide distribution as early as the late Oligocene, which is unique among aplodontid genera. The distribution, the rarity, the unusually small size, and the complex cusp morphology of Ansomys suggest a very specialized ecology for members of this clade.