Diversity of social wasps (Hymenoptera: Vespidae) in Cerrado fragments of Uberlândia, Minas Gerais State, Brazil.

Studies of species survey are important to know the available natural resources and to get useful information about the ecological characteristics of a specific area. There are not studies, on this issue, related to social wasps, in the Triângulo Mineiro region. The present study describes the diversity of species found in fragments of the cerrado region in Uberlândia, MG, and their temporal distribution. The field study was conducted from October 2003 to September 2004, and 43 samplings were carried out using active searching (24) and point sampling (19) methodologies. Twenty-nine species were found in 10 genera, Polybia and Polistes corresponding to 51.5% of the total listing. Mischocyttarus cerberus styx Richards represented 26.5% of the total individuals recorded by active searching and Agelaia pallipes (Olivier) corresponded to 57.6% by point sampling. Two species had their first record for the state of Minas Gerais: Polybia striata (Fabricius) and M. cerberus styx. The studied fragments presented a high level of diversity (H' = 0.66 to 1.16), a large number of rare species and a few common species. To collect the more common species the point sampling method was satisfactory while active searching was better to collect the rarer species. The active searching methodology was more efficient than point sampling, however some species could only be collected by point sampling. These factors showed that in order to carry out a wasp survey, a combination of different collection methodologies seems to be more appropriate.