摘要
采用形态度量学和主成分分析的方法,通过对雅鲁藏布江、伊洛瓦底江、怒江和澜沧江4个水系标本的比较,研究了扁头鮡各地理种群间的形态变异及大鳍鮡的物种有效性。结果表明4个水系的标本相互之间的差异还没有达到亚种水平,应是扁头鮡的地理种群;扁头鮡不同地理种群之间的形态特征,如眼间距、背鳍基长、肛门位置和脂鳍起点位置等性状随海拔高度的下降,自西向东呈梯度变化;前人将腹鳍前长比体长、脂鳍基长比背鳍基长和眼间距比头长等作为大鳍鮡区别于扁头鮡的鉴别特征,并不能将标本区分为大鳍鮡和扁头鮡两个物种,因此大鳍鮡是一个无效的物种,应是扁头鮡的同物异名。
In the present paper,based on the method of morphometrics and principle component analysis,the authors examine 111 specimens of Pareuchiloglanis kamengensis,which collected from the Yarlung Zangbo River,Irrawaddy River,Nujiang River and Lancang River,and also investigate the variations of external morphological characters among different geographical populations of P.kamengensis and the species validity of P.maropterus.In the principal component analysis,the results show that the specimens can not be differentiated from each other as subspecies,and the specimens from the sampling localities should be the geographical populations of P.kamengensis.In the 4 populations,there are distinct variations in the external morphological characteristics including the interorbital width,dorsal fin base length,position of anus and origin position of adipose fin.And these morphological characteristics are closely related to the distributional altitude of the geographical population,such as the characters of interorbital width,dorsal fin base length and position of anus are in direct proportion to altitude height,while the origin position of adipose fin is inversely proportional.The altitude of localities of these 4 rivers is getting lower from the west to east,so these variations are found to be clinal apparently.Our result indicates that P.macropterus is considered as the synonyms of P.kamengensis,because the specimens from the sampling localities can＇t be differed into two or more species.
出处
《动物分类学报》
CSCD
北大核心
2007年第4期814-821,共8页
Acta Zootaxonomica Sinica
基金
中国科学院知识创新工程重大项目(KSCX1-SW-13-04)
国家973计划(2003CB415103)资助.
关键词
扁头鮡
大鳍鮡
主成分分析
物种有效性
地理种群
梯度变异
中国西南部
Parechiloglanis kamengensis,Parechiloglanis macropterus,principal component analysis,species validity,geographical population,gradient variation,Southwestern of China
