Population genetic and historical demography of the ice goby (Leucopsarion petersil) in the Korean peninsula

Abstract

Climatic oscillations in the Pleistocene might have caused population structure in many species inhabiting the Northwest Pacific Ocean. The sea around the Korean Peninsula is an interesting area for phylogeographical research because of dramatic change in sea level during the Pleistocene. The ice goby Leucopsarion petersii (Pisces: Gobiidae) is a kind of coastal sedentary fishes. Like salmon, it ascends to the mouth of rivers for breeding and dies soon. Thus, it has a potential of population structure. We analyzed mtDNA cyt b and nDNA myh6 gene sequences of ice goby to evaluate the population genetic structure and historical demography. Previously, Kokita and Nohara (2011 ) reported Japanese ice goby was divided into East Sea lineage and Pacific Ocean lineage. As a result of the mtDNA cyt b analysis of the Korean goby (three locations), a Korean Strait clade (KO cldae) newly found along the southern coasts of Korea, and belong to the East Sea lineage. The KO clade was genetically close to those of the East Sea lineage, but significantly different (<PsT= 0.227, P=0.000). The KO clade is estimated to have migrated to the Korean peninsula since the sudden demographic expansion of the East Sea linage, and has subsequently evolved into an independent population. On the other hand, in nDNA myh6 analysis, Korean ice goby did not show a population structure, but differed from that of the Pacific Ocean. Unlike previous research results, individuals living in the Korean peninsula formed different clades. Further studies are needed to clarify metapopulation structure using more sensitive makers such as microsatellite or SNP.