Efemeropterofauna (Insecta: Ephemeroptera) do trecho ritral inferior do Rio Campo Belo, Itatiaia, RJ: composição e mesodistribuição

Resumo

Samples from the Campo Belo river located in the municipality of Itatiaia, RJ (22^o28’S; 44^o34’W), in different mesohabitats, registered the occurrence of 22 species, distributed in the following genera (number of species between brackets): Americabaetis (2), Aturbina (1), Baetodes (1), Callibaetis (1), Camelobaetidius (2), Cloeodes (1), Paracloeodes (2) (Baetidae); Leptohyphes (2), Leptohyphodes (1), Tricorythopsis (3), Tricorythodes (1) (Leptohyphidae), Farrodes (1), Massartella (1), Miroculis (1), Thraulodes (1); and Ulmeritoides (1) (Leptophlebiidae). From monthly quantitative collections, taken from October 1999 to September 2000, 3.175 specimens were obtained, 1.002 from the riparian vegetation, 785 from pool litter, 665 from the rocky substratum, 436 from the riffle litter and 287 from gravel/sand. The months with the highest number of individuals were November (595 individuals) and October 1999 (480 individuals). Species number collected in the studied site should be considered in a high degree in compare with other studies carried out in 3rd and 4th orders rivers in Brazil. This fact was probably produced due a most precise identification of the taxa, as a consequence of the recent improves of the taxonomic studies about Ephemeroptera in Brazil and South America.