Presence of a Bisexual Gonad: Implications for Protogynous Sex Change in the White-Edged Lyretail Variola albimarginata (Serranidae)

We analyzed the morphology and gonad structure of Variola albimarginata based on nine specimens (TL 28.2–44.5 cm) collected off Kuchierabu-jima Island, southern Japan. Individuals exceeding TL 40 cm were identified as males, with males significantly larger than females (max TL 33.3 cm). The testes of V. albimarginata all exhibited a central lumen, suggesting a remnant of the ovarian cavity. An individual of intermediate size (TL 37.8 cm), positioned between males and females, possessed a bisexual gonad characterized by the presence of primary oocytes, atretic oocytes, and spermatocytes. These findings suggest the possibility that V. albimarginata undergo protogynous sex change in their life history.