Cavities in bromeliad stolons used as nest sites by Euglossa cordata (Hymenoptera, Euglossini)

Nests of the parasocial bee species Euglossa cordata (Linnaeus 1758) [Brazil] were observed in the laboratory. The construction of the nest, oviposition behavior, times of female and male development and the processes of nest reactivation are described. An analysis of the dominance structure within the female bees and corresponding behavioral events are reported. The resulting monogynous social structures is considered a primitive step towards social life.

The aim of this study was to investigate the diversity and distribution patterns of orchid bees (Euglossina). Cluster and correlation analyses were applied to data extracted from 28 orchid-bee surveys throughout the Neotropical Region. The 28 sampling sites were grouped in three main biogeographic areas that roughly correspond to the Amazonian Basin, the Atlantic Forest and Central America. These three regions, as well as subregions within each of them, correspond approximately to biogeographic components identified through phylogeny-based analyses for other bees and organisms. The Amazonian Forest as a whole has the richest fauna and the highest levels of endemism. The Atlantic Forest, on the other hand, showed the poorest fauna and the lowest levels of endemism. However, a major neotropical biome, in which orchid bees are known to occur, has not been sampled yet, the savanna-like cerrado. At least 30% of the species are endemic to each biome. An updated checklist of the species of Euglossina is provided.