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We investigated the relative growth and sexual maturity (gonadal and morphometric) of Libinia spinosa. Crabs were sampled at Ubatuba from January to December 2000, using trawls. Based on allometric growth, males were grouped into juveniles (MJ), adolescents (MAd) and adults (MA) based on the relationship CPL (major cheliped propod length) vs. CW (cephalothorax width), all with positive allometric growth. For females, the relationship AW (abdomen width) vs. CW allowed segregating juveniles (FJ) from adults (FA), with positive allometric growth for FJ but isometric growth for FA. The morphometric maturity evidenced for MAd varied from 33.7 mm to 34.5 mm and for MA and FA. The size at which 50% of individuals reach the morphometric sexual maturity was L50 = 50.1 mm for males and L50 = 37.3 mm for females. Gonad maturity was L50 = 33.7 mm for males and L50 = 36.9 mm for females. Through relative growth analyses, we identified an adolescent male group (prepuberal phase). These individuals presented mature gonads, enabling them to copulate with females. These adolescent males may reproduce while avoiding competition with adult males, as it happens in other species of Majoidea that present more than two morphotypes in the population. [ABSTRACT FROM AUTHOR]

Artemesia longinaris was analyzed here with respect to reproductive period, recruitment and sexual maturity. Samples were carried out in five transects, monthly, from November 2008 to October 2009, at Fortaleza Bay, north coast of the State of São Paulo, in Brazil, in a region recently decreed as a Marine Protected Area. In total, 1173 individuals were captured: 198 juveniles, 97 rudimentary females, 485 breeding females and 409 adult males. Breeding females and juveniles appeared seasonally and their abundances were positively corelated with bottom water salinity and temperature. The female size at the onset of sexual maturity was estimated as 13.29 mm of carapace length. Our results indicated that Fortaleza Bay can be considered an appropriate place for the reproduction of A. longinaris during summer, because the environmental conditions there in this period are favourable. We suggest that the fishing ban period should be adequate to take into account the reproductive behaviour of other shrimp species, such as A. longinaris, since it is currently based only on the recruitment of species of Farfantepenaeus. [ABSTRACT FROM AUTHOR]