Esse trabalho teve como objetivo conhecer os invertebrados bentônicos, bem como caracterizar os grupos tróficos funcionais existentes no rio Piranhas-Assu, município de Alto do Rodrigues, Rio Grande do Norte. As coletas foram realizadas nos meses de maio (chuva), julho e setembro (seca) de 2002, em trechos diferentes do rio. Foi medida a velocidade da correnteza, a largura, profundidade do rio e temperatura da água. Foram coletados 3525 indivíduos de Insecta e outras classes (Malacostraca, Gastropoda, Bivalvia, Arachnida, Ostracoda e Copepoda). A maior abundância da classe Insecta ocorreu no mês de setembro (seca). A vazão apresentou correlação com a abundância com na Classe Insecta, já a velocidade superficial da água para outras classes. Entre os Insecta observou-se uma maior abundância de predadores, seguida dos coletores, já para as outras classes os raspadores foram mais abundantes. Structure of benthic invertebrate’s community with focus in the aquatic insects of the Piranhas-Assu river, State of Rio Grande do Norte, Northeast, BrazilAbstract. The aim of this work was to verify the benthonic invertebrates, and to identify the functional trophic groups that exist in the Piranhas-Assu, in Alto do Rodrigues municipality, Rio Grande do Norte State. The samples were carried taken on May (rain season), July and September (dry season) from 2002, in different sites in the river. The measurements of water speed, wide, temperature and river deep where made. It was collected 3525 individuals of Insecta and other classes (Malacostraca, Gastropoda, Bivalvia, Arachnida, Ostracoda and Copepoda). Insecta showed a higher abundance in September (dry season). The river discharge showed significant correlation with Insecta classe abundance, and the superficial water speed had correlation with other classes. The insects showed a highest abundance of predators, followed by collectors, in the other classes, the scrappers were the most abundant.

Odonata order, popularly known as dragonflies, comprises insects belonging to group Palaeoptera and presents hemimetabolous development encompassing three life cycle stages: eggs, larvae and adults. Odonata order has three suborders, namely: Anisoptera, Zygoptera and Anisozygoptera - the last one is exclusively distributed in Asia. The aim of the current study is to investigate the composition, abundance and diversity of Odonata larvae in middle Araguari River (Amapá, Brazil) by evaluating space-seasonal fluctuations and their association with different substrates. Eight collection sites were set along the river.  Quarterly samplings were performed within an annual cycle (April/2018 to April/2019) by positioning a trawl "D" net (Rapiché) on the riverbed and scraping the substrate to collect 2L of sample. Odonata richness, abundance and diversity indices were evaluated. Data were statistically treated based on simple descriptive analysis, means, medians and standard deviations, Kruskal-Wallis test (nonparametric data) and ANOVA (parametric data) in the R-statistics Software. Two hundred and ninety-seven (297) individuals were identified; Libellulidae was the most abundant family (80.13%). Diversity and equitability have shown variations between sampling sites (p<0.05) and collection campaigns (p<0.05). Only abundance was influenced by categorical variables such as downstream/upstream river and substrate type. Higher taxonomic resolution, in combination to environmental variables, could help establishing ecosystem relationships that were not identified in the current study.