Differentiation of large-scaled redfin Tribolodon hakonensis (Pisces, Cyprinidae) in the Russian part of the range as inferred from the data of karyological analysis and PCR-RFLP analysis of mitochondrial DNA

Considerable differences in karyotypes of Tribolodon hakonensis from Primorye and the rivers of the Sea of Okhotsk drainage were demonstrated. These differences raise doubts that these fishes belong to one species and point to the necessity of more precise definition of the species status of the southern form of T. hakonensis. The karyological evidence is consistent with the data of mtDNA PCR-RFLP analysis on genetic independence of the southern and the northern forma of T. hakonensis. In the northern form of T hakonensis, variation of the chromosomal arm number was revealed. Specifically, the number of chromosomes was constant (2n = 50), whereas the number of chromosomal arms (NF) constituted 88, 92, and 94, which suggests genetic heterogeneity of the northern form. PCR-RFLP analysis of mtDNA showed that haplotypes of northern T. hakonensis split into two groups with 100% support. Based on comparative phylogenetic and karyological analyses of the Tribolodon species, independent divergence of the southern and the northern forms of T. hakonensis was suggested.