Morphometric differentiation of Labeo catla (Hamilton 1822) (Cyprinidae) in rivers: Possible adaptation to hydrology

Morphological differentiation in the Indian major carp, Labeo catla, Ganga and Narmada rivers was studied using image-based morphometric multivariate analytical techniques. Twenty-three truss-network-based distances connecting 11 anatomical landmarks on fish were measured from digital images of specimens collected seven stations, four which set up along river Ganga, other three stations Narmada. For analysis, five considered, as samples River pooled treated a composite sample (Narmada). The analysis variance showed evidence for significant differences between those rivers. subsequent Linear Discriminant Analysis explained 86% variability by two discriminant functions. This fact suggested existence morphometrically different populations species Ganga. These predominantly distributed middle stretch (Ganga_Middle), Bhagirathi-Hooghly stretch, Padma are isolated barrage that does not allow free bidirectional movement fish. important discriminating characteristics traits head caudal region well body depth relatively narrower angles snout profiles lower depths stretches led to more pointed snouts slenderer bodies. can be used an environmental predictor that, turn, would use developing effective management strategies stock concern.