COI and Cytb data of Lagocephalus spadiceus in eight populations

The Late Pleistocene-Holocene climate fluctuations have had a major impact
on phylogeographic structure and historical dynamics of marine fishes in
the marginal seas of the western Pacific Ocean. Lagocephalus spadiceus is
a high-nutritional and economic-value species in the Southeast China Sea.
The study was to assess the population genetic diversity and demography of
L. spadiceus in the South China Sea (SCS). A sample of 300 specimens from
eight geographic locations along the coast of mainland China and Hainan
Island were obtained for this study. The mitochondrial cytochrome oxidase
I (COI) and cytochrome b (Cyt b) gene datasets had high haplotype
diversity but low nucleotide diversity. The genetic structure and
phylogenetic analyses indicated that there was no significant population
structure among the eight geographic locations. The low genetic diversity
of L. spadiceus was associated with population expansion in the Late
Pleistocene-Holocene period. This was supported by star haplotype
networks, neutrality tests, unimodal mismatch distributions and Bayesian
skyline plots. These findings have important reference value for the
protection of genetic resources. Furthermore, the study illuminates the
complex relationship between Pleistocene-Holocene temperature variability
and phylogeography.