Aiming to elucidate some aspects of the reproductive biology of Ligia exotica Roux, 1828, two populations inhabiting the Estuary of the Patos Lagoon (West Breakwater of Rio Grande Channel and Leonidio Island) were analyzed. Sampling was performed fortnightly, from summer/2003 to winter/2004. Animals were collected manually during one hour. The reproductive season of the species occurred from October to June. No ovigerous females were observed from July to September. In West Breakwater of Rio Grande, 5,376 individuals were captured (1,494 juvenile, 1,748 males and 2,134 females, in which 245 were ovigerous). Sex ratio estimated was 0.78 (M:F). To perform fecundity analysis, 178 ovigerous females with intact marsupium were analyzed. Total length of these females varied from 20.73 to 34.3 mm, and the number of eggs-embryos ranged from 33 to 142. The mean length of sexual maturity of females was 24.65 mm and the mean number of eggs-embryos was 88.0. In Leonidio Island, 5,519 animals were collected (510 juvenile, 1,956 males and 3,053 females, from which 129 were ovigerous). The sex ratio was 0.68 (M:F). While the lowest percentages of ovigerous females were found from September to May, the highest percentage of ovigerous female was observed at the end of March. In this location, 101 ovigerous females were analyzed, with total length varying from 17.62 to 28.61 mm, and the number egg-embryos ranged from 25 to 113. The mean length of sexual maturity of females was 21.43 mm and the mean number of eggs-embryos was 73.8.
Isopoda; Ligia exotica; reproduction; Estuary of the Patos Lagoon; Brazil
