Phylogenetic Relationship of Members of the Genus Rutilus Rafinesque, 1820 in the Southern Caspian Sea (Bandar Turkman, and Shalman and Aras Rivers) Based on Osteological Characters

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.