Studies on morphological variation in three barbin fishes (Cyprinidae:Barbinae) from different water areas of Manipur, India

Abstract

A total of two hundred and seventy samples of three barbin fish species viz. Puntius chola, Puntius sophore and Pethia manipurensis (Cyprinidae: Barbinae) were investigated for morphometric variations from nine different water areas of Manipur. Twenty reliable morphometric characters were measured in each sample and evaluated with individual species and compared same in each study area by various standard analyses of difference to examine the implication of morphometric variations among populations. The species wise and population wise descriptive statistics viz., mean, standard variation, standard error of mean and the Principle Component Analysis (PCA) were carried out. Among the morphometric characters, Pre dorsal length (LPRD), Orbital length (LO) and Post orbital length (LPO) are insignificant having p value of 0.217, 0.259 and 0.215 respectively. The result of first three components by PCA were 69.62 % (1st), 77.627 % (2nd) and 83.214 % (3rd) which are sufficient to describe the variation among the populations. Discriminant function analysis of the first two functions of various measurements of morphometric characters of three fish species under study reveals that specimens of Puntius chola and P. sophore have high morphological variations whereas specimens of Pethia manipurensis have more or less variations among the populations. The detected phenotypical divergence between specimens revealed the fact of existing of morphologically separated stocks within the samples may imply as a possibility among the extent of phenotypic heterogeneity and the geographic distance among the populations. The present study reveals that the population of two species, Puntius chola and P. sophore are separate stock as their geographical sites whereas the population of P. manipurensis is same stock in spite of different geographical sites.