Nidificação incomum de Xylocopa ordinaria em região do Semiárido na Caatinga e preferência por coleta de pólen em flores com antera poricida

• DOI: 10.22533/at.ed.1632329115

• Palavras-chave: -

• Keywords: Xylocopini, semiarid, pollen, nidification, Encholirium spectabile.

• Abstract: The large carpenter bee Xylocopa ordinaria is widespread in Brazil, especially in humid regions. Our aim was to analyze the nesting substrates and pollen sources used by bees of this species in the semi-arid Northeast Region of Brazil. We analyzed eight nests from the Catimbau National Park, Pernambuco, Brazil: six were built in inflorescence scapes of the terrestrial endemic bromeliad Encholirium spectabile and two in dead woody branches of the shrub Hyptis fruticosa. Female X. ordinaria seem to use non-woody substrates when dead wood of trees with thick branches is scarce and where they occur sympatrically with species of the subgenus Monoxylocopa. Females of these latter species provide pre-excavated cavities gnawed into the smooth bromeliad scapes, which are reused by females of X. ordinaria. Flowers with poricidal anthers are the most important pollen resources for X. ordinaria in the Caatinga; around two-thirds of the pollen in brood cells was from species of Cassiinae (Chamaecrista, Senna) and Solanum (Solanaceae). The unbranched galleries in bromeliad scapes do not appear to reduce the number of offspring of X. ordinaria, since these nests contained similar numbers or more brood cells than nests built in thick substrates of dead wood by these and other species of the subgenus Neoxylocopa. The high proportion of pollen from flowers of a few species with poricidal anthers indicates a floral preference of X. ordinaria for these pollen-only flowers.