Fish that, when mature, possess both male (testes) and female (ovary) sex glands at the same time. In such species cross-fertilization can occur during spawning. In other species (e.g. Sparidae, sea bream), the testes develop first, these males turning into females as the fish grow larger and older. Most Serranidae (sea perches) are females first or have both sets of glands equally developed.
Subjects: Ecology and Conservation — Zoology and Animal Sciences.