Bee assemblage (Hymenoptera, Apidae) of an area of natural grasslands in Vila Velha State Park and comparisons with bee surveys in other Brazilian areas of grasslands and cerrado

Abstract

Systematic samplings of bees were conducted at a site in Vila Velha State Park, Paraná state, Brazil, from October 2003 to September 2004. This study aimed at gathering data to compare the bee fauna of grassland sites of Vila Velha with other Brazilian bee assemblages from areas covered with open plant formations. The study area has four hectares and was subdivided in four contiguous subareas of one hectare each for sampling purposes. Bees visiting flowers or in flight were captured with entomological nets. A total of 1.459 specimens, belonging to 122 bee species, 51 genera, 20 tribes and five subfamilies, were collected. The bees visited a total of 93 plant species belonging to 62 genera and 29 families. Summing the present assemblage with that from a previous study in another site at the Park resulted in a total of 222 bee species, 74 of which are species shared between the two sites and 148 were found at one of the sites only. Additional data from historic samplings at Vila Velha rise the known richness to 261 species. The Morisita similarity index between the areas is 0.50 when visited plants species are used as variables and 0.88 when using bee genera and species. The fauna of Vila Velha was compared to other bee assemblages from natural grasslands and cerrado areas using similarity indexes and correspondence analysis. Two groupings, one composed by grasslands sites and the other by cerrado sites, were recovered by the analyses. Also, the correspondence analysis indicates that some bee genera are associated to specific plant formations. Based on this study, the bee fauna of Vila Velha is composed mainly by genera related to grasslands with presence of some elements from the cerrado.