Population genetics of a tropical sea cucumber species (Stichopus monotuberculatus) in China

Stichopus monotuberculatus is a valuable tropical sea cucumber that is distributed throughout the Indo-Pacific Ocean, including Guangxi, Hainan Land and Xisha Islands of China. Increasing demand and over-fishing, however, have seriously depleted the wild populations of this species in China. In this study, we applied both mitochondrial and nuclear DNA markers to characterize the population genetic subdivisions and phylogeographic histories of S. monotuberculatus sampled from Southern China. Based on both classes of molecular markers, our results demonstrated significant genetic structure among S. monotuberculatus populations, and revealed that the three populations (Q, S and B) experienced demographic expansion during the late Pleistocene (50,000–190,000 years BP). This study provides the basic information on natural population structure of S. monotuberculatus that may help to preserve and manage tropical sea cucumbers in China.