The low mitochondrial diversities in lizardfish Saurida elongate: Recent population expansion and selection

To investigate the phylogeographic pattern and historical demography of Saurida elongata, a 463 base pair fragment of the mitochondrial DNA control region was analyzed in 118 individuals collected from five populations in the East China Sea and South China Sea. The results revealed remarkably low nucleotide diversity in S. elongata, which was probably caused by selection during Pleistocene drastic climate fluctuations. Phylogenetic relationship was continuous, but a localized clade was found dominating Beihai population. Mismatch analyses showed that S. elongata experienced both demographic and range expansions. Among these populations, Beihai population expanded latest. Localization of haplotypes clade in Beihai was likely a result of the selection when new habitat was established during a range expansion, and indicated limited gene flow between Beihai and other populations. Our results suggested Beihai population should be managed separately in fishery.