Last species standing: loss of Pocilloporidae corals associated with coastal urbanization in a tropical city state

Coral reefs worldwide are facing multiple severe stressors leading to ecosystem degradation, but local extinctions of species are not well documented. Here, we track the diversity of Pocilloporidae Gray, 1840 coral species-many of which are known to be sensitive to environmental disturbances-on Singapore reefs through time, integrating information from taxonomically verified museum specimens, careful examination of the literature, and DNA sequences. We found that more Pocilloporidae species were detected in the past than at present. A total of five species were historically recorded under Pocillopora Lamarck, 1816; Seriatopora Lamarck, 1816; and Stylophora Schweigger, 1820. Among the five species, only Pocillopora acuta Lamarck, 1816 appears to remain on Singapore reefs. The absence of Seriatopora for over half a century and the recent losses of Stylophora and the other species of Pocillopora are likely caused by habitat loss and other stressors associated with coastal urbanization, which have been further exacerbated by recent bleaching events.