Analysis of cytochrome oxidase 1 (CO1) mitochondrial gene nucleotide sequences in the arctic flounder Liopsetta glacialis and the striped flounder Liopsetta pinnifasciata (Pleuronectidae) from the Okhotsk Sea

The first data on the nucleotide sequences of mitochondrial cytochrome oxidase 1 ( CO1 ) gene of Arctic flounder ( L. glacialis ) and striped flounder ( L. pinnifasciata ) from the Sea of Okhotsk was analyzed. Nucleotide variability of mitochondrial cytochrome oxidase gene in 10 species of Arctic flounder (π = 0.00370) is a little lower than in 28 species of striped flounder (π = 0.00446); all species were obtained in the Taui Bay of the Sea of Okhotsk. Disparity index values calculated based upon the nucleotide variability among Arctic flounder species indicated nonselective substitution mode in this case; at the same time, for the striped flounder species, it indicated that approximately one third of substitutions were selective ones. The rate of nucleotide difference between the species of Arctic and striped flounder confirms the species status of Arctic flounder and striped flounder.