This study was aimed to compare the shapes of Kutum, Rutilus kutum (Kamenskii, 1901) from southern Caspian Sea using landmark based geometric morphometrics. For this purpose, 150 specimens were caught from five stations (30 samples from each station) including Bandar-e Turkman, Mahmood-Abad, Klar-Abad, Kiashahr and Talesh shores. The specimens were anesthetized in 1% clove oil extract, fixed in Buffered Formalin 10% and transported to the laboratory. The fish were photographed and 17 homologous morphological landmarks were digitized on them using tpsDig2 software. The non-shape data including size and direction were removed from data using generalized procrustes analysis. The statistical analysis were done using multivariate analysis PCA, CVA and cluster analysis. The cluster analysis grouped the two population Kiashahr and Bandar-e Torkaman in a single cluster (bootstrap number 58%). The most significant similarities observed between the two groups Kiashahr and Bandar-e Torkaman that separated them from other groups were the more islander liked body, the lower head length and lower body depth. Concerning to the geographic distance between Kiashahr and Bandar-e Turkman, their body shape similarity can be the phenotype plasticity response to their similar environments. Based on this study it can be proposed that Kutum has a wide phenotype plasticity potential.

Landmark based geometric morphometrics and comparison of meristic characters was used to understand potential differences between populations of Waspi in Mashkil and Mokran Basins. 97 specimens of Waspies were caught (64 from Mashkil River and 33 from Sarbaz River). 14 landmarks were digitized on pictures taken from left side of specimens and meristic characters were counted. Data were analyzed using PCA and DFA after procrustes superimposition and data standardization. There are some meaningful shape differences between populations (P<0.001). The body and caudal peduncle in Sarbaz fishes where higher than that of Mashkil fishes, but the peduncle in Mashkil River was longer than Sarbaz fishes. Considering to no meaningful differences between the two populations in meristic characteristics and Due to different conditions in the rivers (vegetation density, water depth, water flow and food availably), the observed differences in shape of fishes could be considered as phenotype plasticity to the conditions of the rivers.

This study was conducted to determine the body shape variation among the populations of the Crested loach, genus Paracobitis, in the southeast Caspian Sea basin using landmark-based geometric morphometrics. In this research, 113 fish samples from Paracobitis genus were sampled from the Tajan, Babolrood, Atrak, Gorganrood rivers in summer using electroshocker. Then, the left sides of the fish samples were photographed by a digital camera. Fifteen landmark-points were digitized on twodimensional images using TpsDig2 software. The obtained results from Landmark data were analyzed and multivariate statistical analyses such as PCA, CVA and cluster analysis (CA) were used and eventually, the Phenotype plasticity patterns of each population related to the shape of overall average of populations were illustrated. The results demonstrated that there was a significant difference among the four studied populations in terms of morphological features (P

This work aimed to study some meristic and morphometric variations among Cyprinion of Iran to find new morphological differences and phenotype plasticity among them. Specimens of six reported species were collected from five Iranian inland water basins. 10 meristics were counted, 12 morphometric were measured and 17 ratios were calculated. The multivariate analysis of variance/canonical variate analysis was used for group comparisons. The meristic and morphometric characters of C. microphthalmum and C. watsoni were widely overlapping and could not distinguish the species. In case of C. kais, it is distinguished from others by having the least head depth, the largest body depth at dorsal fin origin, the most dorsal fin base length/SL, the most pectoral fin length/SL and the most dorsal fin height/SL ratios. Cyprinion milesi is a very distinct species from other congeners based on having the largest head height/body depth, the least body depth/SL, the least dorsal fin base length/SL, the least pectoral fin length/SL and the least dorsal fin height/SL ratios.

In this study, the morphological variation of Oxynoemacheilus bergianus was studied in the different rivers of the Namak Lake and Caspian Sea basins using traditional morphometric method. For this purpose, a total of 76 specimens were collected from eight river systems and after fixation into 4% buffered formalin, transfered to the laboratory, a total of 31 morphological characteristics were measured using digital calipers. After standardization, the morphometric data were analyzed using multivariate analysis including principal component analysis (PCA), canonical variate analysis with p-value obtained from MANOVA (MANOVA/CVA) and cluster analysis (CA). The results showed significant differences in 24 traits between the studied populations (P<0.05), which anal fin depth and the ventral-anal fin distances were main discriminative ones. CVA analysis was able to separate the studied populations. Also, CA placed the Gharesu and Sefid populations in a clade and separate from other populations. The observed differences may be related to phenotype plasticity in response to environmental conditions.

This study was conducted to investigate the morphological variations of Sasanidus kermanshahensis, in the Karkheh river drainage. For this purpose, a total of 162 specimens of the Gardekaneh, Bojin, Dinoarab, Doab, Khoramroud, Maran and Sartang rivers were collected. A total of 30 morphometric traits were measured using digital calipers. After standardization, data were analyzed using Kolmogorov-Smirnov analysis, One-way ANOVA and Duncan grouping, Kruskal-Wallis, principal component analysis (PCA), and Multivariate analysis of variance / canonical variate analysis (MANOVA / CVA). The results showed significant differences in 27 morphometric traits out of 30, and the characteristics, including pre anal length, distance between pectoral and anal fins, pre ventral, distance between pectoral and ventral fins, caudal peduncle length and pectoral fin length were effective traits in separating the studied populations. The results revealed high Phenotype plasticity ability of Sasanidus kermanshahensis in different habitats. Also based the results, this species adapts to the environmental conditions of different habitats by shifting the position of its fins throughout the body.

The present study was conducted to determine the body shape variation among the populations of Iranian goby (P. Iranicus) in the southern Caspian Sea basin using landmark-based geometric morphometrics. A total of 350 specimens of the species were sampled using electro-shocker, and in the laboratory, the left sides of the fish samples were photographed by a digital camera. Fourteen landmark points were digitized on two-dimensional images using TPSDige2 software. The obtained data from Landmarks were analyzed using multivariate statistical analyses including PCA, CVA, and cluster analysis (CA). The phenotype plasticity patterns of each population related to the shape of the overall average of populations were illustrated. The results of the study demonstrated that there was a significant difference among the studied populations in terms of morphological features. Dendrograms revealed that both sexes could be divided into five groups related to the localities of specimens. Analysis of MANOVA/CVA showed that females of P. Iranicus have a high separation rate among the provinces, while males of Mazanderan province had significant isolation from males of Guilan and Golestan provinces. The two provinces showed a high overlap in the morphological characteristics. The results of the study can improve understanding of growing phenotype patterns plasticity of these fishes in the water bodies of different river systems from the southern basin of the Caspian Sea as well as identifying species of P. Iranicus populations in the southern basin of the Caspian Sea rivers.

The phylogenetic analysis of the members of the genus Rutilus from the southern Caspian Sea was analyzed based on the osteological characteristics. For this purpose, three population of Roach from Bandar-e Turkman, Shalmanrood River and Aras River (each 10 specimens) as in-group and 10 specimens of Kutum fish (Rutilus kutum) were used as out-group. The fish were stained and cleaned according to standard methods for osteological examination based on direct observation. Phylogenetic analysis was performed based on 24 osteological character states and the phylogenetic tree was constructed based on maximum parsimony algorithm using TNT software. The results showed the monophyly of the three Roach populations. The Turkman population with 7 automorphic characters was the plesiomorphic (65% bootstrap number) and the other two Roach groups formed sister taxa. The osteological differences of the Aras population compared to other populations of the Caspian Sea maybe due Phenotype plasticity corresponding to their environmental factors. Based on similarities observed between R. rutilus and R. caspicus from the Kura, it can be proposed that they belong to same species. Also it can be proposed that the R. caspicus from Turkman may be a distinct taxon.

This study was conducted to investigate the interspecies morphological variation of Sabzug (Cyprinion watsoni) in response to environmental factors using geometric morphometrics method in Southern and Southeastern Iran. Hence¡ nine populations including 270 specimens of Sabzug were collected from four Southern and Southeastern basins of Iran during summer 2012 using electrofishing. The specimens were anesthetized in clove solution 1gl-1¡ fixed into 4% formalin and then transported to the laboratory for further examinations. The left view of specimens was photographed and fifteen landmark-points were defined and digitized on 2D images using tpsDig2 software. The shape data were analyzed based on Principal Component Analysis (PCA)¡ Canonical Variate Analysis (CVA) and Cluster Analysis (CA). The results revealed a significant difference between populations in terms of body shape (P

During 2018-2019, to study the morphological diversity of Oxynoemacheilus elsae, a total of 51 specimens were collected from the Godarchai, Barandozchai, Zarrinehrood and Mahabadchai rivers, Urmia Lake basin using electrofishing. From the collected samples, 22 morphometric characteristics were measured using a digital caliper with an accuracy of 0.1 mm. Also, in geometric morphometric (GM) method, the side of the samples were photographed, and 14 landmarks were digitized using tpsDig2 software. The extracted data were analyzed to understand morphological variation between the studied populations using multivariate analysis i.e. PCA, MANOCA /CVA and cluster analysis. The results showed a significant difference between the studied populations in terms of the morphological characters (P<0.05). In traditional method, there were significant differences in 10 traits between the studied populations (P<0.05). The main differences in GM method were related to the body and head depth, mouth position and caudal peduncle height. The observed morphological variations show the high adaptability of this species, especially in the pectoral fin length and body height traits with habitat adaptation.