In the present paper, based on the method of morphometrics and principle component analysis, the authors examine 111 specimens of Pareuchilogtanis 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.
Yao Jing-Long; Yan Yun-Zhi; Gao Yong; Li Kun; Chen Yi-Feng (Chenyf@ihb.ac.cn).Study on morphological variations of pareuchiloglanis kamengensis and species vailimy of P-Macmropterus in southwestern of China,Acta Zootaxonomica Sinica,2007,32(4):814-821