Data from: Beyond the Coral Triangle: high genetic diversity and near panmixia in Singapore’s populations of the broadcast spawning seastar Protoreaster nodosus

The Coral Triangle is widely considered the most important centre of marine biodiversity in Asia while areas on its periphery such as the South China Sea, have received much less interest. Here we demonstrate that a small population of the knobbly sea star Protoreaster nodosus in Singapore has similarly high levels of genetic diversity as comparable Indonesian populations from the Coral Triangle. The high genetic diversity of this population is remarkable because it is maintained despite decades of continued anthropogenic disturbance. We postulate that it is likely due to broadcast spawning which is likely to maintain high levels of population connectivity. To test this, we analysed 6140 genome-wide single nucleotide polymorphism (SNP) loci for Singapore’s populations and demonstrate a pattern of near panmixia. We here document a second case of high genetic diversity and low genetic structure for a broadcast spawner in Singapore, which suggests that such species have high resilience against anthropogenic disturbances. The study demonstrates the feasibility and power of using genome-wide SNPs for connectivity studies of marine invertebrates without a sequenced genome.

珊瑚三角区（Coral Triangle）被广泛认定为亚洲最重要的海洋生物多样性中心，而其周边的南海（South China Sea）等区域则受关注程度较低。本研究证实，新加坡境内的一小种群瘤状海星（Protoreaster nodosus），其遗传多样性水平与珊瑚三角区内印尼境内的同类种群不相上下。该种群的高遗传多样性尤为引人注目——即便经历了数十年持续不断的人为干扰，其遗传多样性仍得以维持。我们推测，这一现象可能源于播散产卵（broadcast spawning）策略，该策略有助于维持高水平的种群连通性。为验证这一假说，我们对新加坡种群的6140个全基因组单核苷酸多态性（SNP）位点进行了分析，结果显示其种群结构近乎泛交。本研究记录了新加坡境内第二类兼具高遗传多样性与低遗传结构的播散产卵物种，这表明此类物种对人为干扰具备较强的抗干扰能力。本研究证实了利用全基因组SNP开展无参考基因组海洋无脊椎动物种群连通性研究的可行性与效能。