Vertical distribution of orchid bees (Hymenoptera: Apidae: Euglossini) in an Amazon forest fragment

Euglossine bees are key pollinators of various plant species in the Neotropical region. Therefore, studying euglossine bee ecology is important for the development of conservation strategies. This study aimed to evaluate the vertical distribution of these bees in a "terra firme" forest fragment in the state of Rondonia, Brazil. The collections were carried out fortnightly from June 2017 to May 2018. The bees were sampled in the understory (1.5 m in height) and the canopy (12 m in height), using six aromatic compounds. A total of 9793 specimens were collected, representing 42 species of four genera. Statistically, the abundance of euglossines was higher in the understory, while the richness did not differ between strata. Eulaema Lepeletier, 1841 and Exaerete Hoffmannsegg, 1817 species were more abundant in the understory, while Euglossa Latreille, 1802 species were more abundant in the canopy stratum. Eufriesea Cockerell, 1908 species showed no difference in abundance between strata. In addition, nine new occurrences were recorded for the Rondonia state.