Reproductive biology of Leporinus taeniatus Lütken (Pisces, Anostomidae) in Juramento Reservoir, São Francisco River basin, Minas Gerais, Brazil

The reproductive biology of the piau-jejo Leporinus taeniatus Lütken, 1875, an endemic species from the São Francisco River basin, was studied by using macroscopical and histological techniques. A total of 121 males and 94 females were captured quarterly, between March 2002 and February 2003 in the Juramento Reservoir. Females were larger than males, indicating sexual dimorphism. Stages of gonadal maturation were defined from histological analyses and gonadosomatic index. Peaks of maturing/mature and spawned/spermiated fishes has occurred in period December-February. L. taeniatus presented total spawning and group-synchronic development of the oocytes. The gonadosomatic index accompanied gonad maturation in both sexes, and coelomic fat presented lower levels during maturing/mature stage, indicating fat consumption during the reproductive period. Stomach repletion index presented higher values during spawned and spermiated stages, indicating greater food ingestion after the reproductive period