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The geometric morphometrics method was applied to study the morphological differences in 95 specimens of Kura barbel (Barbus lacerta, Heckel 1834) collected from three riverine ecosystems of the Sefidrud basin, viz. Taleghan, Totkabon and Kloraz Rivers.  For this purpose, the left sides of the specimens were photographed. Then, 14 Landmark-points were defined and digitized on 2D pictures using Tpsdig2 software. The landmark data, after generalized Procrustes analyzing, were analyzed by PCA, CVA with p-value obtained from permutation test and cluster analysis. The results showed a significant differences between the populations in terms of body shape (P