SEXUAL DEVELOPMENT AND SEXUALITY IN THE NASSAU GROUPER

Hermaphroditic sexual patterns are widespread among teleosts and are e specially characteristic of certain perciform families. Among the most diverse groups of hermaphroditic species are the groupers, hamlets an d sea basses of the family Serranidae. Like other groupers, the epinep heline serranid, Epinephelus striatus, the Nassau grouper, has long be en assumed to exhibit monandric protogyny (a form of hermaphroditism i n which all males derive from adult females by sex change). Histologic al and demographic data, however, indicate that the sexual pattern of this species is not monandric, and that, unlike other group species, t he juveniles pass through a bisexual stage of gonadal development. Sex uality in the Nassau grouper is essentially gonochoristic, with potent ial for sex change. The combination of bisexuality and gonochorism is previously undescribed in the serranids.