Coral reefs provide essential goods and services but are degrading at an alarming rate due to local and global anthropogenic stressors. The main limitation that prevents the implementation of adequate conservation measures is that connectivity and genetic structure of populations are poorly known. Here, the genetic diversity and connectivity of the brooding scleractinian coral Seriatopora hystrix were assessed at two scales by genotyping ten microsatellite markers for 356 individual colonies. S. hystrix showed high differentiation, both at large scale between the Red Sea and the Western Indian Ocean (WIO), and at smaller scale along the coast of East Africa. As such high levels of differentiation might indicate the presence of more than one species, a haploweb analysis was conducted with the nuclear marker ITS2, confirming that the Red Sea populations are genetically distinct from the WIO ones. Based on microsatellite analyses three groups could be distinguished within the WIO: (1) northern Madagascar, (2) south-west Madagascar together with one site in northern Mozambique (Nacala) and (3) all other sites in northern Mozambique, Tanzania and Kenya. These patterns of restricted connectivity could be explained by the short pelagic larval duration of S. hystrix, and/or by oceanographic factors, such as eddies in the Mozambique Channel (causing larval retention in northern Madagascar but facilitating dispersal from northern Mozambique towards south-west Madagascar). This study provides an additional line of evidence supporting the conservation priority status of the Northern Mozambique Channel and should inform coral reef management decisions in the region.

中文翻译：

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育雏珊瑚 Seriatopora hystrix 的种群遗传学揭示了西印度洋强烈的遗传分化模式

珊瑚礁提供了基本的商品和服务，但由于当地和全球的人为压力因素，珊瑚礁正在以惊人的速度退化。阻碍实施充分保护措施的主要限制是种群的连通性和遗传结构鲜为人知。在这里，通过对 356 个个体菌落的 10 个微卫星标记进行基因分型，在两个尺度上评估了育雏石珊瑚 Seriatopora hystrix 的遗传多样性和连通性。S. hystrix 表现出高度分化，无论是在红海和西印度洋 (WIO) 之间的大范围内，还是在东非海岸的小范围内。由于如此高水平的分化可能表明存在多个物种，因此使用核标记 ITS2 进行了单倍网分析，确认红海种群在遗传上与 WIO 种群不同。根据微卫星分析，可以在 WIO 内区分三组：(1) 马达加斯加北部，(2) 马达加斯加西南部以及莫桑比克北部的一个地点（纳卡拉）和 (3) 莫桑比克北部、坦桑尼亚和肯尼亚的所有其他地点. 这些连接受限的模式可以用 S. hystrix 的中上层幼虫持续时间短和/或海洋学因素来解释，例如莫桑比克海峡中的涡流（导致幼虫滞留在马达加斯加北部，但促进了从莫桑比克北部向西南的扩散马达加斯加）。这项研究提供了额外的证据支持莫桑比克北部海峡的保护优先地位，并应为该地区的珊瑚礁管理决策提供信息。