Population panmixia and the Pleistocene demographic expansion of spotty belly greenling Hexagrammos agrammus in the East Sea and Northwest Pacific

Abstract

 The population genetic structure and historical demography of spotty belly greenling, Hexagrammos agrammus, which has limited distribution in the Northwest Pacific, was assessed with partial sequences of the mitochondrial DNA (mtDNA) cytochrome b and the control region (D-loop). A total of 103 individuals were collected from four sites located at the Korea Strait (Southern coast of Korea) and the East coast of Korea and two places in the Pacific coast of Japan. For all the populations, nucleotide diversities were low (0.006 -0.009) while the haplotype diversities were as high as 0.92 to 0.97, indicating that the fish has undergone a recent population expansion after experiencing bottleneck. Star-shaped patterns of haplotype networks as well as the significant negative values of Tajima's D and Fu's F S corroborate the recent population expansion. Mismatch distribution analysis reveals that the demographic expansion of the species started during the 2 nd half of the Middle Pleistocene Series approximately 141,000 -406,000 years ago. Hierarchical analysis of molecular variance (AMOVA), the pairwise population statistics (F ST ), and the exact test of haplotype differentiation demonstrate no significant genetic differentiation among populations investigated, suggesting that spotty belly greenling is panmictic in the East Sea and the Pacific coast of Japan.

Genetic population structure in the swimming crab,Portunus trituberculatusand its implications for fishery management

“…the Bohai Sea, the Yellow Sea, the East China Sea and the South China Sea, changed drastically in area and environments through the late Quaternary glacial cycles. The distribution and abundance of marine species also experienced changes through the loss and regaining of habitats, especially during the middle to late Pleistocene glacial-interglacial cycles (Dynesius & Jansson, 2000; Hewitt, 2000; Habib et al ., 2015). In particular, this study reveals that a major demographic expansion in the populations of P. trituberculatus occurred in the middle Pleistocene (Table 1, Figure 3).…”

Cryptic diversity in the inshore hagfish, Eptatretus burgeri (Myxinidae, Pisces) from the northwest Pacific

“…Thus, E. burgeri in Kyoto might have experienced extinction and recolonization in anoxic bottom condition during glacial and interglacial cycle. Some deep-sea species might have experienced a rapid decrease in anaerobic or hypoxia environment after the western coast of Japan was separated from Pacific Ocean during the LGM, which might have influenced their low genetic diversity (Adachi et al 2009;Sakuma et al 2014;Habib et al 2015).…”