A structured inventory of harvestmen (Arachnida, Opiliones) at Juruti River plateau, State of Pará, Brazil.

Abstract

The first structured inventory of harvestmen in the Brazilian Amazon Rain Forest was carried out at Juruti municipality, Pará State. The sampling protocol was done in three plots of (1 ha each) non-flooded upland forest, on the Juruti River plateau, nearly 60 km from the right margin of the Amazon river, and one plot in a floodplain forest area, at the Amazon river margin. To ensure assessment of the majority of potential habitats, seven collecting techniques were used, resulting in 466 individuals from 28 species. Each upland site provided 16-18 species. Flooded forest habitat was undersampled, and only five species were recorded. From the seven collecting methods employed, litter manual sorting resulted in the highest number of species per sample, and beating tray the highest ratio of individuals per sample. These two collection techniques, along with nocturnal ground search, were the most effective sampling techniques for a protocol for collecting harvestmen in this site.