REPRODUCTIVE CYCLE OF Leporinus copelandii (Pisces: Anostomidae) FEMALES FROM THE LOWER PARAÍBA DO SUL RIVER BASIN, RJ – BRAZIL

Abstract

The aim of this study were investigate the reproductive biology of the fish <em>Leporinus copelandii</em>, a specie at risk of extinction in the lower Paraíba do Sul River basin. During a period of 14 months, a total of 143 females of red-piau were captured, between Itaocara and Campos dos Goytacazes cities (RJ, Brazil). A histological study shows four stages of the oocyte development (I, II, III and IV) and five stages of the reproductive cycle of females: rest (1), initial maturation (2A), intermediary (2B), advanced (2C) and spawned (4) were identified. The pattern of <em>L. copelandii</em> oocyte development suggests development type synchronous in two groups, characterizing total spawning. Spawned females were captured in November, two months after the peak of frequency of competent females for reproduction. Histologically, a little occurrence of empty follicles was observed in spawned females. The medium diameter of the type IV oocyte of the spawned females (1475.1 ± 884.3mm) was significantly larger (Tukey, P <0.001; VC = 41.73%; n = 259) than advanced maturation females (1202.6 ± 245.3mm), what allows suggesting that the study place probably doesn't represent the reproductive area of <em>L. copelandii</em>.