한국산 흑대기의 형태 및 유전분석에 의한 지리적 변이

Abstract

The cynoglossid fishes are used for food in Japan and Korea, and among them, Paraplagusia japonica lives all over the sea of Korea. Therefore, it is essential to understand genetic diversity and population structure of P. japonica for the appropriate management and conservation. Morphological and molecular analyses of 132 individuals of P. japonica collected from six localities in Korea were conducted to identify population structure. Canonical discriminant analysis results showed that the West Sea population (Incheon) slightly differed from the South (Tongyeong, Busan) and East Sea populations (Pohang, Donghae, Sokcho). Similar results were also shown in Kruskal-Wallis test of meristic characters. Furthermore, neighbor-joining and maximum-likelihood trees based on 849 base pairs of mitochondrial DNA cytochrome b sequences showed that the Korean P. japonica was divided into two lineages (designated as A and B) with a high significance (ΦST = 0.0781, P < 0.001). These differences might have been caused by paleo-climatic change and/or current oceanic conditions. There were no significant differences between two lineages in the South-East Sea in meristic and morphometric characteristics. This can be explained by secondary contact between two lineages in the South-East Sea. In order to clarify if gene flow occurs between the two lineages, further research using more sensitive markers such as microsatellite is needed.