Morphology plays a central role in determining diet. Knowledge of ecological and morphological relations between a species and its ecosystem is highly relevant. The aims of this study are to describe the diet and the lower pharyngeal jaw (LPJ) of Cichlasoma portalegrense and to test for the existence of ontogenetic and spatial patterns in its diet. Samplings took place in four sampling sites in Viamão, including two at the Refúgio de Vida Silvestre Banhado dos Pachecos. Collected individuals were grouped in accordance with size categories and dissected. Food items were identified and quantified for each size category in each sampling site, according to the volumetric method, related to frequency of occurrence. Four linear measurements of the LPJ were carried out. The quantity and quality of their teeth were ascertained. Teeth arrangement was also analysed. Cichlasoma portalegrense is omnivorous with a tendency to carnivory and feeds on pelagic and benthic items from different origins. It shows neither ontogenetic patterns nor spatial variation in its diet. The species can feed on any possible food resource, thus being an advantage regarding the others. The LPJ has five types of teeth, is generalist without specializations, which is an adaptive advantage, since it is already adapted to selection pressures from different kinds of food. The shape of the LPJ and teeth distribution clearly show a same arrangement, regardless of fish size categories.

中文翻译：

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Cichlasoma portalegrense (Cichliformes: Cichlidae) 中饮食、咽下颌和个体发育之间的相互作用

形态学在决定饮食方面起着核心作用。物种与其生态系统之间的生态和形态关系的知识是高度相关的。本研究的目的是描述 Cichlasoma portalegrense 的饮食和下咽颚 (LPJ)，并测试其饮食中个体遗传和空间模式的存在。采样在维亚芒的四个采样点进行，其中两个在 Refúgio de Vida Silvestre Banhado dos Pachecos。收集到的个体按照大小类别分组并解剖。根据与发生频率相关的体积方法，确定并量化每个采样点中每个尺寸类别的食品。对LPJ 进行了四次线性测量。确定了他们牙齿的数量和质量。还分析了牙齿排列。Cichlasoma portalegrense 是杂食性的，有食肉倾向，以不同来源的远洋和底栖物品为食。它既没有表现出个体遗传模式，也没有表现出饮食的空间变化。该物种可以以任何可能的食物资源为食，因此是其他物种的优势。LPJ 有五种类型的牙齿，是没有专业的通才，这是一个适应性优势，因为它已经适应了来自不同食物种类的选择压力。无论鱼的大小类别如何，LPJ 的形状和牙齿分布都清楚地显示出相同的排列。该物种可以以任何可能的食物资源为食，因此是其他物种的优势。LPJ 有五种类型的牙齿，是没有专业的通才，这是一个适应性优势，因为它已经适应了来自不同食物种类的选择压力。无论鱼的大小类别如何，LPJ 的形状和牙齿分布都清楚地显示出相同的排列。该物种可以以任何可能的食物资源为食，因此是其他物种的优势。LPJ 有五种类型的牙齿，是没有专业的通才，这是一个适应性优势，因为它已经适应了来自不同食物种类的选择压力。无论鱼的大小类别如何，LPJ 的形状和牙齿分布都清楚地显示出相同的排列。