Taxonomic status of six populations of the Gobiids (Teleost, Gobiidae) in the southern Caspian Sea basin using COI gene

Morphological similarities of the populations and species of the genus Ponticola in the southern Caspian Sea make their identification difficult based on the provided keys. Molecular markers are used as a supplementary tools to better understanding of the fishes’ taxonomic statues. This study was conducted to understand taxonomic statues of gobiids from 6 rivers (Siah, Zaringol, Babol, Tajan, Sefid vis. Bijar and Kisum populations, and Kelsian) in Southern Caspian Sea basin based on DNA barcoding using mitochondrial COI gene by reconstructing phylogenetic tree based on ML and BI methods and drawing haplotype network and assessment of the geographic and genetic distances. The results show a mean genetic distance (K2P) of 0.69-1.68 between the studied populations that is too low for considering them as distinct species based on the genetic criteria. Also, BI and ML cladograms and haplotype network showed all populations are haplotypes of P. gorlap.