ABSTRACT

The stone flounder, Platichthys bicoloratus (Basilewsky, 1855) (family Pleuronectidae), has a restricted distribution in the Northwest Pacific, including Korea, Japan, China, and Taiwan. Although P. bicoloratus is an important commercial fish in the Northwest Pacific, few studies have assessed its population structure for appropriate management. This study investigated the morphological and molecular variation in P. bicoloratus collected from five localities: Goseong (East Sea), Pohang (East Sea), Yeosu (Korea Strait), Seocheon (Yellow Sea), and Daecheongdo (Yellow Sea). Canonical discriminant analysis of data on 27 morphometric characters showed separation of the Goseong population from those in the remaining regions except Yeosu population. Pairwise analyses of 720 bp of cytochrome b sequences from mitochondrial DNA showed that the Goseong population differed from the other regional populations. In the pairwise FST based on microsatellite loci showed that Goseong population differed from the other regional populations except Pohang population, and Yeosu population differed from Seocheon and Daecheongdo populations, in contrast to the mtDNA results. Although there are differences in the results from each analysis, our comprehensive results suggest that P. bicoloratus may be treated as three independent management units (northern East Sea vs. Korea Strait+southern East Sea vs. Yellow Sea).