Sexual development and sexuality in the Nassau grouper


  • Y. Sadovy,

    1. Fisheries Research Laboratory, Department of Natural Resources, P.O. Box 3665, Mayaguez, Puerto Rico 00681
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    • Current address: Department of Ecology and Biodiversity, Hui Oi Chow Science Building, University of Hong Kong, Pokfulam Road, Hong Kong.

  • P. L. Colin

    1. Coral Reef Research Foundation, P.O. Box 70, Weno, Chuuk, Federated States of Micronesia, 96942
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Hermaphroditic sexual patterns are widespread among teleosts and are especially characteristic of certain perciform families. Among the most diverse groups of hermaphroditic species are the groupers, hamlets and sea basses of the family Serranidae. Like other groupers, the epinepheline serranid, Epinephelus striatus, the Nassau grouper, has long been assumed to exhibit monandric protogyny (a form of hermaphroditism in which all males derive from adult females by sex change). Histological and demographic data, however, indicate that the sexual pattern of this species is not monandric, and that, unlike other group species, the juveniles pass through a bisexual stage of gonadal development. Sexuality in the Nassau grouper is essentially gonochoristic, with potential for sex change. The combination of bisexuality and gonochorism is previously undescribed in the serranids.