Nesting biology and flower preferences of Megachile (Sayapis) zaptlana

Abstract

Megachile zaptlana is a solitary cavity-nesting leafcutter bee widely distributed in Brazil. Using two models of trap nests in sugarcane monoculture and agroecosystem environments in Pernambuco, northeastern Brazil, we studied the nesting biology of this species. We obtained 193 nests, 39.4% in the monoculture and 60.6% in the polyculture site. The nests consisted of a linear series of brood cells coated with a mixture of chewed leaves with sand, often followed by a long empty vestibular cell and an operculum at the entrance. A nest contained on average 2.4 (± 1.3) brood cells. Emergence patterns indicate that the species has a multivoltine life cycle without diapause and a peak emergence in the drier months from October to December. The sex ratio females: males, was 1:0.43. Females founded their nests in holes with diameters of 5–10 mm, with a preference for 6 mm (68%). Pollen analysis of larval diet showed that the species is polylectic, and brood cells contained pollen from 19 plant species, especially from the families Asteraceae, Rubiaceae, Plantaginaceae, and Fabaceae. In the studied agroecosystems, ruderal plants were the most important nectar and pollen sources for Megachile zaptlana. Given that Megachile zaptlana is polylectic and multivoltine, it might be a good candidate for future use as a managed pollinator.