First Data on Genetic Polymorphism of the Deepwater Goby Neogobius bathybius (Gobiidae) from the Russian Part of Its Range

The study presents the results of polymorphism analysis of fragments of two mitochondrial DNA genes for the deepwater goby Neogobius bathybius (Kessler, 1877) from the Caspian Sea near Makhachkala— the cytochrome c oxidase subunit 1 gene (co1) and the cytochrome b gene (cyt b). The deepwater goby from this locality is characterized by a high degree of polymorphism in both genes. Thus, six co1 haplotypes were identified in a sample of 13 individuals, and each of the 10 individuals analyzed was found to carry a different cyt b haplotype. Despite the high level of diversity observed in this sample, the newly revealed sequences were found to be closely related to haplotypes from populations from the Iranian coast of the Caspian Sea. The genetic distances between our and Iranian samples for co1 and cyt b are 0.3% and 0.9–1%, respectively. However, most of the haplotypes revealed in our sample were identified for the first time. In addition, some morphometric characteristics of the deepwater goby from the Caspian Sea near Makhachkala were described.