descriptive osteology of squalius orientalis from urmia lake basin of iran

osteological features are important to study the taxonomy and phylogenetic relationship of fishes. since there is no information is available about osteological features of squalius orientalis , therefore this study was aimed to provide a detailed description of the osteological features of this species from the urmia lake basin of iran and comparing it with population of s. orientalis from the caspian sea basin. for this purpose, the specimens were collected from zarineh river of the urmia lake basin and cleared and stained with alizarin red s and alcian blue for osteological examinations. finally, a detailed osteological features of this species was provided and compared with those of the caspian sea basin. based on the results, having a longer pre-vomer, dorsally oriented parasphenoid alar, longer ventral blade-shaped process of the orbitosphenoid, concaved masticatory plate, pointed ascending process of the palatine, concaved posterior margin of the opercle, and a small posterior process of the cleithrum can differentiate s. orientalis of the urmia lake basin from those of the caspian sea basin. in addition, the observed osteological difference suggest that both studied populations belong to same taxon.