Distribution of Odonata sampling effort in Brasil – basis for choosing prioritary areas for faunistic inventories

Abstract

There is an urgent need to prioritize conservation areas, so that the invested resources protect as much biodiversity as possible, especially in developing countries. A way to select such areas is to estimate the biodiversity distribution but this strategy is constrained by the lack of knowledge and/or by the inaccessibility of the available information on species distribution. Based on a database on Odonata distribution in Brazil, it is shown that the sampling-effort and the largest numbers of recorded odonate species and genera are concentrated in areas with large number of researchers. The 6203 records employed here are distributed in only 29% of the national territory. The species richness is concentrated mainly in the states of Rio de Janeiro, Minas Gerais and São Paulo, in the Amazon River varzea and in some isolated points, such as Cuiabá (Mato Grosso state). We suggest that the sampling and inventory efforts are increased for Odonata, especially in the Brazilian northeast and areas in the Brazilian and Guyana Shields, for which there is practically no information available.