Genetic Diversity of Thread-sail Filefish Stephanolepis cirrhifer Populations in Korean Coastal Waters Inferred from Mitochondrial DNA Sequence Analysis

The genetic diversity and population genetic structure of thread-sail filefish, Stephanolepis cirrhifer (Temminck & Schlegel), were examined with a nucleotide sequence analysis of a 495bp fragment of the 5'-end of the cytochrome b gene in 113 fish collected from five populations from the south and east coasts of the Korean Peninsula. Seventeen variable nucleotide sites and 16 haplotypes were defined. The observed haplotypes had a shallow haplotype genealogy and no geographical association. Most of the populations had high haplotype diversity and low nucleotide diversity, and significant negative values for Fu's $F_S$, suggesting rapid, recent population growth from an ancestral population and sudden population expansion. The estimated pairwise fixation indices ($F_{ST}$) indicate that substantial gene flow occurs among these populations. Thread-sail filefish in the South Sea of Korea and East Sea Korean populations forms a single panmictic population. Thus, thread-sail filefish in these areas should be treated as one management unit.