Sexual pattern and gonadal development in the Caribbean parrotfish {it Sparisoma radians/} (Osteichthyes, Scaridae)

This study examined the sexual pattern of the Caribbean parrotfish Sparisoma radians (Osteichthyes: Scaridae) through the histological analysis of the reproductive tract in adult males, adult females and juvenile fish. S. radians is a protogynous hermaphrodite commonly found in seagrass beds and occasionally on coral reefs. The majority of males presented features characteristic of secondary males. The remnants of an ovarian cavity was found in the testes and sperm duct. Seventeen percent of males showed features characteristic of primary males. The testes were solid, and no ovarian cavity was found in the sperm duct. Examination of juveniles revealed that sexual differentiation is highly plastic in the size at which fish mature. The presence of two morphologically different types of males and the analysis of sexual differentiation suggest that S. radians is a protogynous, diandric hermaphrodite.