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Os inventários de espécies fornecem amplo conhecimento sobre a distribuição, ecologia e riqueza dos táxons tornando-o uma ferramenta importante para programas de conservação de biodiversidade e gestão dos ecossistemas. Os organismos inventariados neste estudo são pertencentes à classe Oligochaeta, um importante táxon da fauna aquática continental e um dos grupos mais importantes na ciclagem de matéria orgânica nos ecossistemas de água doce. Dessa forma, este estudo tem como objetivo realizar o levantamento das espécies de Oligochaeta em três córregos urbanos (Córrego Himalaia, Ribeirão da Bocaina e Córrego Bocaina) do município de Bocaina, localizado na região central do estado de São Paulo. Para isso, as amostras de sedimento foram coletadas em sete pontos com o auxílio de uma rede (malha 0,25 mm) pelo método de varredura. O material coletado foi triado para obtenção dos organismos, fixado com formalina 10% e identificado até nível de espécie. Foram registrados 20 táxons de um total de 1395 organismos, distribuídos em 10 gêneros (Allonais, Aulophorus, Bothrioneurum, Brinkhurstia, Dero, Limnodrilus, Nais, Opistocysta, Pristina e Slavina) e 4 famílias: Família Naididae Opistocystidae, Alluroididae e Enchytraeidae. Assim, o presente inventário obteve uma riqueza de 20 táxons, representando aproximadamente 23% das 86 espécies registradas em ecossistemas aquáticos brasileiros. Por fim, muitos estudos ainda precisam ser realizados para fornecer dados mais completos sobre a distribuição e ecologia desse táxon, para enfatizar sua importância como bioindicadores de qualidade da água e para manutenção do equilíbrio ecológico em ambientes aquáticos.

The construction of reservoirs in streams or rivers has altered the aquatic ecosystems. One of these impacts is the change from lotic to lentic systems, influencing the structure and the functioning of this environment and, consequently, modifying the aquatic fauna. Aquatic macroinvertebrates are the most commonly biological indicators in the assessment of aquatic ecosystems, because they reflect the environmental changes and participate in nutrient cycling and energy flow. The aim of this study was to analyze the macroinvertebrates community of a stream located in the Institute of Biotechnology (Ibiotec-Uniara) and to evaluate the possible environmental impact of damming. Two samples were collected from two different sites, downstream and upward the dam where the macroinvertebrates were collected, using a "D" aquatic net, by the sweeping method, and were identified using specific literature. A total of 289 organisms were identified belonging to 15 taxons of macroinvertebrates. The diversity index (Shannon), species richness (Margalef), and dominance index were calculated. In site 1, we found a low species diversity, but with a high abundance of organisms, with the dominance of the Chironomidae family. In site 2, we found more diversity, but low abundance, with the predominance of the Oligochaeta. Apparently, the impoundment has not influenced the diversity of the aquatic fauna, however, the low diversity of riparian vegetation observed in the sites and the presence of the sugar-cane culture in the adjacent areas could be influencing the richness and the diversity of the organisms.

Aquatic fauna can be used as good indicators of the integrity of an aquatic environment. Because of some characteristics such as easiness of sampling and identification at family level and low general cost, the aquatic macroinvertebrates have been used as aquatic bioindicators, mainly in lotic environments. The present study had as main objective to analyze the macroinvertebrates of the Pinheirinho stream, located in the Basalto Park, with the purpose of investigating the conservation of the area. The macroinvertebrates were collected using a D-frame aquatic net (250 µm), including riffle and pools areas, during 5 minutes, as recommended by Fontoura (1985). Samples were taken to the laboratory, washed through a sieve with 0.21mm of mesh, selected on illuminated trays and fixed with 70% alcohol. The taxonomic identification was achieved at family level based on the available published data. In general, the results point to the necessity of environmental education in the Park, especially in its adjacent areas.

The aim of the study was to analyze the diversity and community structure of aquatic insects associated with species of submersed macrophytes with different morphological complexity in relation to leaf structure. Sampling occurred in raining and dry periods at Ribeirão das Anhumas, Américo Brasiliense/SP. Four macrophytes were analyzed: Vallisneria sp., Eleocharis sp., Egeria najas and Ottelia sp. The entomological community was identified up to the family level, and at tribe level for Chironomidae. The community structure was analyzed using diversity indices of Simpson, Equitability evenness, relative participation of functional category and taxa dominance. The dispersion of faunal composition between the different collection periods was analyzed using a n-MDS with Morisita index. The structure of the insect community associated with macrophytes with different structural morphologies was analyzed using structural similarity calculated by the Bray-Curtis index. Seventeen families were identified from five orders, a total of 1642 specimens. The family Hydropsychidae (Trichoptera) presented eudominance (52.6%), followed by the tribe Pentaneurini (Chironomidae) (13.8%) and family Trichoryithidae (Ephemeroptera) (10%). The results showed that there were no large diversity variations in the analyzed macrophyte species and the sampling periods. The predator and collector functional groups were predominant. The n-MDS analysis indicated the absence of seasonal variation and, the similarity analysis indicated that macrophyte E. najas and Otellia sp., presented similar fauna structure, differing from other analyzed species. The results demonstrated that the morphological structure of macrophytes may have different structures of aquatic insect communities.

In the last decades, anthropic activities such as agriculture activities, industrial and urban effluents and urban areas have been pointed as the main responsible for the alteration and degradation of the aquatic ecosystems. One way of analyzing the water quality of these environments is to study the aquatic microinvertebrated fauna. The present study aimed at analyzing the environmental water quality of Anhumas Stream in the city of Araraquara, SP, Brazil, by studying its aquatic macroinvertebrate community. Two samplings were carried out, being one in February and the other in October, 2008. Three sections of the stream were chosen for study, and two samples were collected at each site totalizing 12 samples. 35 families of macroinvertebrates were collected, totalizing 644 individuals. The Chironomidae family was the dominant one with approximately 57% of the total of collected organisms. The metrics of environmental evaluation using stream macroinvertebrates pointed to the conservation of the Anhumas stream, considering that we found a higher richness of families and a higher percentage of Ephemeroptera, Plecoptera and Tricoptera (EPT) than the ones found in streams with similar environments characteristics near to Araraquara region. The results pointed to the importance of conserving this area as a reference for water´s quality in the region of Araraquara.