Composição da comunidade de aranhas de solo (Arachnida, Araneae) : estudo comparativo entre áreas inundáveis e não inundáveis na região norte do Pantanal de Mato Grosso, Brasil

Abstract

Arthropods in flood environments present particular behavioral and survival strategies determined by the type, frequency, amplitude and intensity of seasonal flooding and, therefore, can be used as biological models for the identification of factors that determine biodiversity patterns in these areas. The spiders comprise a significant portion of the abundance of arthropods in terrestrial environments, and how they are exclusively predators, they act strongly on the organization of animal communities. Considering the importance of studies on biodiversity and mechanisms maintainers of their standard and stability, particularly in priority areas for conservation as the Pantanal of Mato Grosso, this study evaluated the effect of periodic flooding and habitat structure on the composition and structure of ground spider communities in a comparative study of flooding (murundus fields and pasture areas) and non-flooding lands (cordilheiras) in the floodplain of the Pantanal of Mato Grosso. It was collected a total of 2,581 spiders, 2,139 (82.9%) of them employing pitfall traps and 442 (17.1%) using mini-Winkler extractor, representing 34 families and 84 species. Lycosidae, Linyphiidae, Ctenidae, Gnaphosidae and Zodariidae were the predominant families. The spider community structure is influenced by seasonal variation, based on seasonal periods and annual hydrological cycles, while the composition varies only according to the multiannual cycles. Thus, it is observed that the seasonality influences the species richness, probably due to the adaptability of most species of spiders to flooding and non-flooding environments in this region.