Fish skeletal structure is one of the biological taxonomy that is widely used in taxonomic studies and morphological flexibility to understand the evolution of fish. During evolution, due to the separation of habitats, divergences occur, especially in the structure of the body, which ultimately leads to a distinction between populations. Comparisons of osteology of Iranian cichlid populations ( Iranocichla .) with the aim of evaluating and comparing the osteology of this species populations in Makran and Hormoz basins. For this purpose, samples of Iranian cichlid from the Hormoz Basin (16 specimens of fish from the Mehran River, 8 specimens of the Khorogo hot spring, 3 specimens of the Chark river, 4 specimens of the Chegin River and 9 specimens of the Kol river) and the Makran Basin (8 specimens of the Kahir river) were collected and fixed in formalin and kept in alcohol at the Isfahan University of Technology Museum. Samples were stained with Alizarin Red and Alsian Blue. Then the osteological features of this species were described in detailes and compared among the populations. The results displayed that the structure of caudal skeleton and the number of vertebral parapophyses showed the highest differences among the studied populations. According to the results of this study, there was a variation in the structure of the caudal skeleton in all individuals in each population, and it seems that the population of the Kol river has reached a relative stability compared to other populations, and other populations in terms of ostological charecteris have a great diversity among and within individuals. Therefore, osteological characteris are not suitable for separating these populations. The results of this study, in addition to helping to recognize the characteristics of this species, help us to better understand the evolutionary processes of our populations in response to different environmental conditions and to better understand its biological characteristics, also can serve as a reference for comparing with other reported populations of Iranocichla . and other species of cichlid fish used in future taxonomy surveys.
