During a program of limnological characterization, the macrobenthic community was evaluated in a section of river Ribeira, in the area included of the future reservoir UHE Tijuco Alto. In the four expeditions, during XII/95 to IX/96, samples were collected in five stations included between Criminosa stream and Eldorado city (both in São Paulo state). Faunistic data analyzed (taxonomic composition, relative participation of different taxa, and community biotic indices) permitted establish an ecological evaluation of the area. From fifteen macroinvertebrate families identified, Chironomidae (Diptera) and Elmidae (Coleoptera) were the more representatives, contributing respectively with 67.7% and 16.9% of total macroinvertebrates. Among Chironomidae predominated typical genera of sand bottom of lotic environments, with higher participation of Caladomyia > Polypedilum (Tripodura) > Polypedilum (Polypedilum). Community indices (H' = 2.65; I Mg = 4.50) and biotic indices (IB BMWP = 74; IB H = 1.75) point towards good biological quality of the water in river Ribeira.
Diptera; Chironomidae; river macroinvertebrates; faunist river evaluation; biotic index
