The use of geometric morphometric method in evaluating sexual ‎dimorphism (Case study: ‎Cyprinion macrostomum)‎

This study was conducted to investigate the sexual dimorphism of Cyprinion macrostomum in the Little Zab River using traditional and geometric morphometric methods. For this purpose, during 2021, 37 specimens (21 females and 16 males) were collected using an electrofishing device. After determining the sex of the collected specimens, 18 morphometric characteristics were measured using a digital caliper. Also, to extract body shape data in geometric method, photographs were taken from the left sides of both males and females. Then, 16 landmark-points were digitized in tpsDig2 software. The extracted data were analyzed using multivariate statistical analysis including principal component analysis (PCA), T.tests and Mann-Whitney.The results of discriminant function analysis (DFA) and T-test of the body shape showed a significant difference between males and females (P<0.05). The males have more body depth, posterior snout, and shorter caudal peduncle length than the females. Males and females had significant differences in 8 morphometric traits (P<0.05). The results of the  present study confirmed the performance of traditional and geometric morphometric methods in the differentiation of the C. macrostomum sexes.