Suchergebnisse

Euglossini bees are found from southern USA to Central Argentina and southern Brazil. Variations in latitude and altitude can influence the distribution of these bees. This study focused in recognizing the Euglossini species in northern Santa Catarina state, evaluating the distribution over the gradient between sea level and 800 meters altitude. The bees were collected in six locations, between Spring and Summer from 2013 to 2015, using cotton balls containing the following odor baits: benzyl benzoate, 1,8 cineole, eugenol, menthol and vanillin. A total of 794 bees were sampled, belonging to 10 different species, including a possible new species. In terms of abundance Eufriesea Cockerell, 1908 (4 species) accounted for 552 individuals, followed by Euglossa Latreille, 1802 (5 species) with 218 and Eulaema Lepeletier, 1841 (2 species) 24 individuals. Five species were not found above altitude of 400 meters. Eufriesea violacea Blanchard, 1840, Euglossa annectans Dressler, 1982, and Eulaema nigrita Lepeletier, 1841 were the only species found in every location along the altitudinal gradient, but their abundance declines toward higher altitudes. The results surpassed the known orchid bee species for Santa Catarina state from 9 to 14 and confirmed the expected tendency of richness and abundance reduction toward the highlands.tendency of richness and abundance reduction toward the highlands.

Island biotic communities tend to be less diverse than mainland communities. This work aimed to describe the bee community of Ilha Grande, Babitonga Bay, Santa Catarina, Brazil, and its interactions with floral resources. Entomological net-sweeps were used to collect bees in flight or on flowering plants for 7 hours a day, monthly, for two years. A total of 785 specimens were sampled in the field, belonging to 50 species or morphotypes with four indeterminate individuals. The most representative subfamilies were Apinae (58.59%), Halictinae (40.43%), Colletinae (0.8%) and Megachilinae (0.1%), while the most abundant species were Apis mellifera (305 individuals), Dialictus sp. 1 (182) and Dialictus sp. 2 (32). The presence of Apis mellifera decreased diversity throughout the year. Relative abundance and richness of Halictinae were greater on the island on mainland. Richness of Apinae was lower on the island than that on the mainland due to the absence of Meliponina. A total of 55 botanical species were identified in association with bees, with Schinus terebinthifolius (105 visits) being the most visited. Interaction network metrics indicate an asymmetric, nested, and poorly specialized network. The results corroborate the Theory of Island Biogeography and demonstrate little interference/favoring of some taxa as well as the absence of others.