Morphometric analysis of Squalius namak Khaefi et al. 2016 in Khaznagh and Ghare-Chai rivers

The Namak Chub, Squalius namak, is a newly described cyprinid from Namak basin of Iran, but there is little information on its body variations. To investigate the population differences, fifty-two specimens (37 from Khaznagh and 15 from Ghare-Chai) of Squalius namak (Teleostei: Cyprinidae) were captured by seine net during the summer of 2010. After anesthetizing, specimens were transferred to Ichthyology Museum (IUT-IM) for further studies. The specimens were photographed from their left side and 13 landmarks were defined on the photos in Tpsdig2 software. Procrustes analysis (GPA) was performed to eliminate non-shaped effects, the size, direction and position of the specimens. Principal Component Analysis (PCA), Discriminant Function Analysis (DFA) and wireframe graph were used to analyze these populations. The results of this study showed a significant difference between the two populations. The major differences observed were the depth of the body, head size and the position of the mouth. The Ghare-Chai River population has a greater body depth and smaller head length. Further, the position of the mouth in the Khaznagh river population was more inferior compared to the Ghare-Chai River population.