Fatty acids play important role in several biological processes taking place in crustaceans, such as reproduction and molting. The aim of the current study is to evaluate the seasonal variation in fatty acid concentration and profile in crab species Ucides cordatus exploited in Brazilian mangroves. Eight samplings were performed throughout one year and 30 adult specimens - 15 males and 15 females - were selected - it totaled 240 individuals. Muscle and hepatopancreas were freeze-dried and had their fatty acid profiles analyzed through gas chromatography. Analysis of variance, principal component analysis and cluster analysis were carried out in order to find patterns among sample groups. Sixteen fatty acids were found in hepatopancreas; palmitic acid presented the highest concentration in male (22.25–33.72%) and female individuals (24.97–31.74%). On the other hand, five fatty acids were identified in muscle tissues - linoleic acid was the fatty acid recording the highest concentration in male (20.51–27.49%) and female individuals (21.62–28.05%). Based on multivariate analysis, fatty acid concentrations played major role in group formation. With respect to the hepatopancreas, reproduction and pre-ecdysis phases were more clearly distinguished for female than for male individuals. Higher fatty acid concentrations were found in the muscles of the pos-ecdysis group. Overall, fatty acid concentrations have shown different behaviors for both tissues and for both sexes - the main variations were observed during the breeding and intermolt phases.

脂肪酸在甲壳类动物的几个生物过程中发挥重要作用，例如繁殖和蜕皮。本研究的目的是评估蟹种Ucides cordatus脂肪酸浓度和分布的季节性变化在巴西红树林中开采。一年中进行了八次抽样，并选择了 30 个成年样本——15 名男性和 15 名女性——总共 240 人。将肌肉和肝胰腺冷冻干燥，并通过气相色谱分析其脂肪酸谱。进行方差分析、主成分分析和聚类分析以发现样本组之间的模式。在肝胰腺中发现了 16 种脂肪酸；棕榈酸在男性（22.25-33.72%）和女性（24.97-31.74%）中的浓度最高。另一方面，在肌肉组织中发现了五种脂肪酸——亚油酸是男性（20.51-27.49%）和女性（21.62-28.05%）中浓度最高的脂肪酸。基于多变量分析，脂肪酸浓度在群体形成中起主要作用。关于肝胰腺，女性的生殖和蜕皮前阶段比男性个体更明显。在蜕皮后组的肌肉中发现了更高的脂肪酸浓度。总体而言，脂肪酸浓度对两种组织和两种性别都表现出不同的行为——主要的变化是在繁殖和换羽阶段观察到的。