Selection of a permanent attachment site of coral larvae can be a critical determinant of recruitment success affecting the structure of coral communities and underpins the ability of coral reef ecosystems to recover from disturbance. Settlement specificity of a threatened coral in Sanya reefs, Acropora millepora, was tested by measuring the larval metamorphosis preferences and post-settlement survival in response to crustose coralline algae (CCA) species Hydrolithon reinboldii and other substrata. In the no-choice experiments, the larvae of A. millepora had similar rates of total metamorphosis with the presence of CCA regardless of the algae tissue being alive or not, and settlement success induced by CCA was higher than by other substrata (tile or glass). In the paired-choice experiments, when CCA was in presence, the coral larvae preferred the surface of the dish and the side of living CCA. In the absence of CCA, total larvae metamorphosis was lower than in the treatments where CCA was present. New recruits of A. millepora had approximately 68% mean survival on all the settlement substrata after 2 weeks maintained in aquaria with flow-through seawater similar to the coral larval sampling site, but with no coral spat survival in the treatments where CCA was absent. However, there were statistical differences between the larvae survival of dead CCA and glass chips treatment and the others where CCA was present. Our results were consistent with the conclusion that some CCA species could facilitate coral larval settlement and post-settlement survivorship, highlighting the importance of substrata selection success for facilitating coral recruitment in the threatened coral reefs.

珊瑚幼虫永久附着位点的选择可能是影响珊瑚群落结构的补充成功的关键决定因素，并支持珊瑚礁生态系统从干扰中恢复的能力。通过测量响应于壳珊瑚藻 (CCA) 物种Hydrolithon reinboldii和其他基质的幼虫变态偏好和定居后存活，测试了三亚珊瑚礁中受威胁的珊瑚Acropora millepora 的定居特异性。在无选择实验中，A. millepora的幼虫无论藻类组织是否存活，CCA 存在的总变态率相似，CCA 诱导的沉降成功率高于其他基质（瓷砖或玻璃）。在配对选择实验中，当 CCA 存在时，珊瑚幼虫更喜欢培养皿的表面和活的 CCA 的侧面。在没有 CCA 的情况下，总的幼虫变态低于存在 CCA 的处理。新兵A. millepora在与珊瑚幼虫采样点相似的流经海水的水族箱中维持 2 周后，所有沉降基质的平均存活率约为 68%，但在没有 CCA 的处理中没有珊瑚幼苗存活率。然而，死亡的 CCA 和玻璃碎片处理的幼虫存活率与其他存在 CCA 的幼虫存活率存在统计学差异。我们的结果与一些 CCA 物种可以促进珊瑚幼虫定居和定居后存活的结论一致，突出了基质选择成功对于促进受威胁珊瑚礁中珊瑚补充的重要性。