The gametogenic aspects of mussel Perna perna (Linnaeus, 1758) from Itaipu Lagoon, Niterói, were studied through November 1998 to October 1999. Microscopic analysis was carried out at low and high dry magnifications, as well as under oil immersion. The animals collected showed variation of size from 4.8 to 9.1 cm in total length and from 2.0 to 3.9 cm in total width. Most advanced gonadal stage was detected through May, August and October of 1999 for female specimens. Male advanced gonadal stage occurred in September of the same year. The sex-ratio (M:F) for P. perna was 64:52.
Perna perna; gonadal cycle; special-staining methods; Itaipu Lagoon; Rio de Janeiro