Orbicella annularis, the boulder star coral (family Merulinidae), is a massive dome-forming scleractinian coral historically one of the most important framework-building corals on Caribbean reefs, with hemispherical colonies reaching over 2 m in diameter and some individuals estimated to exceed 500 years of age. The species is listed as Endangered by the IUCN due to massive population declines from bleaching, disease, and ocean acidification. Genomic data have been generated for this species and are available in public databases, enabling comparative studies of cnidarian evolution and ecology.