The aim of this study is to determine the influence of environmental variables on the time distribution of assemblages of Chironomidae in the Upper Paraguay River. The samples were collected from November 2004 to October of 2005. To consider the diversity of habitats in the region, nine different sampling points were sampled and 2988 individuals were collected, distributed in 34 species, eight tribes and three subfamilies. The genus Labrundinia sp.1, Polypedilum (Asheum) and Polypedilum (Tripodura) occurred almost every month during the study. Richness and abundance were higher during the dry period of the year, and the genus Polypedilum was the most abundant. There was evident the effect of the environmental variables on the attributes of diversity in the Upper Paraguay River.
Pantanal; sazonal distribution; structure community; richness; abundance
