长尾姬鼠分类地位的探讨

THE FIELD MICE (Apodemus) IN WULIANG MOUNTAIN WITH A DISCUSSION OF A.orestes

长期以来长尾姬鼠 (Apodemusorestes)的分类地位一直不确定。基于在云南中部无量山区采集的大量姬鼠类标本 ,经单变量和多变量分析 ,长尾姬鼠明显区别于中华姬鼠 (A .draco)。主要鉴别特征在于体长、尾长及尾长与体长的比例 ,且相关分析表明 ,该两种的尾长与体长具显著的相关性。而对无量山姬鼠的生态地理分布研究显示 ,长尾姬鼠与中华姬鼠具完全同域分布 ,因此认为长尾姬鼠是一有效种。无量山区现有姬鼠 3种 :A .chevrieri、A .draco和A .orestes,前者因其体形较大、尾较短、体色明显偏黄而明显区别于后两种。

The palaearctic field mice (genus Apodemus ) mainly have a palaearctic distribution and marginally occur in Oriental region in southern China and the Himalayas. Among Chinese Apodemus,A.orestes is often aligned with A.draco. This paper is designed to clarify the systematic problems of A.orestes based on 245 specimens collected in WuliangMountain,CentralYunnan.Ofthespecimens,147 with complete skulls have been used for multivariate and monovariate analyses. The principal component analysis gave out two groups, A.chevrieri and draco orestes group,while the discriminant analysis showed that all specimens were correctly classified in A.chevrieri,A.draco and A.orestes with the former widely different from the latter two. An univariate analysis demonstrated that A.draco and A.orestes had significant difference in head and body length ( t =78 359, P <0 001),tail length ( t =71 555, P <0 001),the rate of tail length to head and body length ( t =70 550, P <0 001),cranial breadth ( t =75 886, P =0 025) and palatal bridge length ( t =60 803, P =0 030). Apodemus draco has a wide distribution in Wuliang Mountain,which overlaps with A.chevrieri in lower elevations less than 2?300?m in farmlands and jungle habitat,overlaps with A.orestes in higher elevations over 2?450?m in forest habitat. Therefore, Apodemus orestes is a valid species.