Phylogeography of the Kura Barbel Barbus cyri De Filippi as Inferred from mtDNA Data.

Caucasian barbels of the genus Barbus are a genetically poorly studied group of cyprinids. This article presents the first detailed study of the phylogeography of the Kura barbel B. cyri (229 specimens from 52 locations) using two molecular markers of mtDNA, the cytochrome b gene and the control region. By analyzing haplotype networks, the complex genetic structure of the population system of the Kura barbel was revealed. The discovered genetic subdivision correlates weakly with the geographical distribution of populations. We suggest that climatic oscillations, Caspian Sea level fluctuations, and the tectonic activity resulted in the repeated secondary contacts, as well as temporary isolation of some populations (e.g., Lenkoran, Sevan, Lower Kura, southern coast of the Caspian Sea) during the Pleistocene–Holocene. At the same time, genetic subisolation of the population of the upper-middle reach of the Kura River from the population in the Lower Kura was revealed. Along with other data on the endemism of the ichthyofauna of the middle reach of the Kura, this finding favors the hypothesis of a local refugium in the Kura basin. [ABSTRACT FROM AUTHOR]