Estrutura da comunidade de abelhas (Hymenoptera: Apoidea: Apiformis) de uma área na margem do domínio da caatinga (Itatim, BA)

Abstract

Neotropical Entomology 34(1): 015-024 (2005) The Bee Community (Hymenoptera: Apoidea: Apiformis) of an Area in the Border of the Caatinga Domain (Itatim, BA -Brazil)ABSTRACT -Several standardized surveys of bee communities undertaken in Brazil in the last few decades have allowed a comparative approach to the search for generalized patterns of community structure. In this paper the results of a standardized year-round bee survey undertaken in Itatim, Northeastern Brazil, in the semi-arid caatinga domain (12 º 42'S; 39 º 46'W) are presented. The main objective was to investigate the composition of community, the relative abundance of the species and their flight periods. Bees were collected monthly, from september/1996 to november/1997, totaling 180h. The total of 1189 specimens were collected, belolging to 60 species. Apidae was the most diversified family, with 37 species. The genera with more species were Centris Fabricius, Megachile Latreille, and Xylocopa Latreille. A high dominance was observed, as in most of caatinga areas already studied. Apis mellifera L. was the predominant species, with 51% of the total number of individuals captured, and occurred all year long. The other predominant species had a much lower abundance, as: Dialictus opacus (Moure) (6.2%), Perditomorpha sp. (4.0%), Trigona spinipes (Fabricius) (3.8%), Frieseomelitta languida (Moure) (3.7%) and Xylocopa grisescens Lepeletier (3.0%). It is suggested that some characteristics of the community are due to its ecotonal nature, as the presence of some species with a probable marginal occurrence in the caatinga, and the extended period of flight activities of Megachilidae, Halictidae and Colletidae, resulting in a high number of species in activity during the driest four months of the year.KEY WORDS: Bee assemblage, relative abundance, phenology, Northeastern Brazil, semi-arid RESUMO -A realização de estudos padronizados das comunidades de abelhas tem permitido a abordagem comparativa entre vários ecossistemas e a investigação da existência de padrões na estruturação dessas comunidades na região Neotropical. Este estudo foi conduzido ao longo de um ano em Itatim, Nordeste do Brasil, no domínio semi-árido da caatinga. O objetivo do trabalho foi investigar a composição e as relações de abundância entre as espécies de abelhas, seus períodos de atividade de vôo, e compará-los aos de outras áreas estudadas anteriormente. As abelhas foram coletadas a cada 30 dias, entre setembro/1996 e novembro/ 1997, entre as 6:00h e as 18:00h, totalizando 180h de amostragem. As abelhas foram capturadas com rede entomológica, em flores ou em vôo. Foram coletados 1189 indivíduos, compreendendo 60 espécies. Apidae foi a família mais diversificada, com 37 espécies. Os gêneros com maior número de espécies foram Centris Fabricius, Megachile Latreille e Xylocopa Latreille. Como observado na maioria das áreas de caatinga anteriormente estudadas, Apis mellifera L. foi a espécie mais abundante, com elevada dominância, compreendendo 51% do número total de indivíduos captur...

Trap-nesting bees (Hymenoptera, Apoidea) in areas of dry semideciduous forest and caatinga, Bahia, Brazil

“…On the other hand, the species richness in the caatinga in Ipirá (7 species) was similar to that found for sand dunes areas in Salvador, Bahia (7 species) by VIANA et al (2001), and higher than those reported by AGUIAR & MARTINS (2002) for habitats of open savanna (5 to 8 species) and closed forest at Guaribas Biological Reserve (2 species, in Mamanguape, Paraíba). The low species richness of bees found in the caatinga and in the sand dunes coincides with the patterns observed from collecting of bees at flowers (MARTINS 1994, AGUIAR & MARTINS 1997, VIANA 1999, VIANA & ALVES-DOS-SANTOS 2002, AGUIAR & ZANELLA 2005. According to some authors (GARÓFALO 2000) the species richness found in their studies may be underestimated because not all species present in the habitats were attracted to nest in the traps.…”

Survival strategies of stingless bees (Melipona subnitida) in an unpredictable environment, the Brazilian tropical dry forest

“…Despite the native occurrence of approximately 20 known species of stingless bees (Zanella 2000), the currently most abundant highly eusocial bee in most areas of the Caatinga is the Africanised honey bee (Aguiar and Zanella 2005), a South American hybrid of the African honey bee Apis mellifera scutellata and European races. Contrary to pure European races, the Africanised honey bee, which had been introduced into the Brazilian Northeast in the 1960s, has succeeded in establishing wild populations in this region (Freitas et al 2007).…”

Biologia de nidificação de Centris (Hemisiella) trigonoides Lepeletier (Hymenoptera, Apidae, Centridini)

“…Esta sugestão pode ser reforçada pelo pequeno número de indivíduos que tem sido coletado em flores em diferentes ecossistemas, cujas comunidades de abelhas foram amostradas de forma padronizada e sem escolha para a captura de espécimens e espécies (MARTINS 1994, SILVEIRA & CAMPOS 1995, SILVA & MARTINS 1999, ZANELLA 2003, REBELO et al 2003, AGUIAR & ZANELLA 2005.…”