Truss morphometry and otolith microchemistry reveal stock discrimination in Clarias batrachus (Linnaeus, 1758) inhabiting the Gangetic river system

Landmark-based truss morphometric analysis and elemental composition in otoliths were used to identify the stock structure of Clarias batrachus inhabiting the river Ganga and its tributaries: Yamuna and Gomti rivers from India. Eleven morphometric landmarks were chosen to construct truss network on the fish body and inductively coupled plasma atomic emission spectrometry was used to analyze 12 trace elements in otoliths. The morphometric data showed that the discriminant functions DFI and DFII accounted for 49.5% and 30.1%, respectively of group variability. Twenty-four out of 30 morphometric measurements showed statistically significant (Univariate ANOVA, P