Sexual reproduction in the Caribbean coral genus Isophyllia (Scleractinia: Mussidae)

The sexual pattern, reproductive mode, and timing of reproduction of and , two Caribbean Mussids, were assessed by histological analysis of specimens collected monthly during 2000-2001. Both species are simultaneous hermaphroditic brooders characterized by a single annual gametogenetic cycle. Spermatocytes and oocytes of different stages were found to develop within the same mesentery indicating sequential maturation for extended planulation. Oogenesis took place during May through April in and from August through June in . Oocytes began development 7-8 months prior to spermaries but both sexes matured simultaneously. Zooxanthellate planulae were observed in during April and in from June through September. Higher polyp and mesenterial fecundity were found in compared to . Larger oocyte sizes were found in than in , however larger planula sizes were found in . Hermaphroditism is the exclusive sexual pattern within the Mussidae while brooding has been documented within the related genera , and . This study represents the first description of the sexual characteristics of and provides an updated description of .