We investigated the population dynamics of the spider crab Libinia ferreirae, focusing on the frequency distribution of individuals in size classes, sex ratio and the action of environmental variables (temperature, salinity, texture and organic matter content in the sediment) on reproduction and recruitment. Monthly collections were made in the Ubatuba region from January 1998 to December 2000. A total of 222 individuals were collected, including 123 juveniles (males and females), 43 adult males, 25 non-ovigerous adult females and 31 ovigerous females. Unlike most adult brachyurans, there was no significant size difference between sexes, and sexual dimorphism seems to be a varying characteristic for this crab genus. The reproductive period and recruitment were continuous with peaks that could be related to water mass dynamics and higher food availability in the Ubatuba region. In addition, our results increase knowledge about part of the life cycle of L. ferreirae, which could be useful for comparative studies.

中文翻译：

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通过巴西东南海岸的繁殖和种群特征揭示蜘蛛蟹 Libinia ferreirae 的动态

我们调查了蜘蛛蟹的种群动态利比尼亚，重点关注个体在大小等级、性别比例和环境变量（沉积物中的温度、盐度、质地和有机质含量）对繁殖和补充的作用的频率分布。从 1998 年 1 月到 2000 年 12 月，在乌巴图巴地区进行了每月收集。共收集了 222 只个体，包括 123 只幼鱼（雄性和雌性）、43 只成年雄性、25 只非产卵成年雌性和 31 只产卵雌性。与大多数成年短吻蟹不同，两性之间没有显着的体型差异，性别二态性似乎是这种蟹属的一个不同特征。繁殖期和补充持续出现高峰，这可能与乌巴图巴地区的水团动态和更高的食物供应有关。此外，L. ferreirae，这可能对比较研究有用。