COMUNIDADE DE ABELHAS (HYM., APOIDEA) DA CAATINGA E DO CERRADO COM ELEMENTOS DE CAMPO RUPESTRE DO ESTADO DA BAHIA, BRASIL

Resumo

This study is an outcome of standardized periodical sampling of the bees and plant species visited by bees in the caatinga (Casa Nova, Bahia, Brazil) and in the cerrado with campo rupestre elements (Lençóis, Bahia, Brazil). During one year (from October 1987 to September 1988), in each 15 days, samples were obtained at Casa Nova and at Lençóis. Bee species composition, relative abundance, phenology of families and species were analysed. Comparisons were made with other studies in Neotropical region. The total sample, at Casa Nova, consisted of 1249 individuals and 42 species. At Lençóis, the total sample consisted of 1761 individuals and 147 species. The percentage ratios of various groups in species and (inparentheses) individual numbers, at Casa Nova, were: Colletidae 7.1 (9.8), Andrenidae 4.7 (0.6), Halictidae 11.9 (0.9), Megachilidae 11.9 (1.0), Anthophoridae 38.1 (5.1), Apidae 26.2 (82.4). At Lençóis, the percentage ratios were: Colletidae 6.1 (3.3), Andrenidae 1.4 (0.1), Halictidae 23.8(26.6), Megachilidae 29.9 (12.1), Anthophoridae 24.5 (16.7), Apidae 14.3 (41.2). At Casa Nova, Anthophoridae and Apidae showed the highest species richness, together accounting for more than 64% of total species number. At Lencois, Megachilidae was the family with the highest species number (44 species), followed by Anthophoridae and Halictidae with nearly the same species number (36 and 35 species, respectively). In both areas Apidae showed the predominance in individuals, a pattern observed in the majority of studies in Neotropical region As in other surveys in Neotropical region, the relative abundance at a species level, in both areas, was characterized by the occurrence of numerous species represented by a limited number of individuals, and of afew predominant species. Species diversity was higher at Lençóis. The low species diversity observed in the caatinga seems to confirm MICHENER (1979) hypothesis that diversity is lower inarid tropical regions in relation to arid temperate areas. At specific level, Apis mellifera and Trigona spinipes were predominant at Casa Nova (38.9% and 17.5% of total individuals, respectively). At Lençóis, Trigona spinipes (16.4%), Pereirapis rhizophila (16%) and Apis mellifera (12.4%) were predominant. In relation to the phenology, at family level, at Casa Nova, Apidae and Anthophoridae showed flight activities during most part of the year. Colletidae, Andrenidae, Halictidae and Megachilidae showed flight activities mostly In the rainy season. At Lençóis, the observed phenological pattern was similar to other humid tropical climates, i.e., bee families showed flight activities throughout the year, although some groups were more active in different periods of the year.