Identification and Morphological Characteristics of Clethrionomys rufocanus, Eothenomys shanseius, E. inez and E. eva from the USSR, Mongolia, and Northern and Central China

概要

論文の詳細を見る
Museum specimens of 236 red-backed voles from the southern part of the USSR, Mongolia, and the Provinces of Inner Mongolia, Hopei, Shansi, Shensi, Kansu, Chinghai, Hupeh, and Szechwan in China were compared with 69 specimens of Clethrionomys rufocanus from Finland. The distance from the most posterior edge of the upper 3rd molar (M3) to the most anterior point on the incisor (I-M3) correlated positively with ages determined by the developmental stages of molar roots in the year-round samples from Finland. In the samples from Finland and from eithg localities in the USSR and Mongolia 46°N or more (Gropu A), most of the skulls measuring I-M3=14.6 mm or more did not have alveolar capsules to indicate root development. On the other hand, in the samples from 11 localities in northern China situated from 37° to 41°N, alveolar capsules indicating rootless molars were observed even in skulls where I-M3=14.6 mm or more. In the samples from 18 localities in central China from 31° to 39°N, all skulls had an I-M3 of 14.6 mm or less, and alveolar capsules were found even in adult females having prominent mammae on the skin. Adult animals larger than the smallest I-M3 class (0.3 mm interval) of the adult females in the respective localities are divided into two groups (Groups B and C) by the relation between I-M3 and interorbital width (IOW). Group B animals had larger I-M3 and smaller IOW, including the holotype of Craseomys shanseius, whereas those of Group C had smaller I-M3 and larger IOW. Group C specimens could be further divided into two groups (C-1 and C-2) based on the relation between I-M3 and tail length (TL). Given and increase in I-M3, specimens in Group C-1 had a shorter TL, including the holotypes of Microtus (eothenomys) inez and M. (E.) nux, whereas those of Group C-2 had a longer TL, including the holotypes of M. (Caryomys) eva, M. (Caryomys) alcinous, and Craseomys aquilus. Group A specimens are identified as Clethrionomys rufocanus by the presence of roots and the age variation of molar patterns on ...
Mammalogical Society of Japanの論文

Identification and Morphological Characteristics of Clethrionomys rufocanus, Eothenomys shanseius, E. inez and E. eva from the USSR, Mongolia, and Northern and Central China

スポンサーリンク

概要

著者

関連論文

スポンサーリンク