Genetic diversity and population structure of orchid bees from the Brazilian savanna

Abstract

Based on microsatellite markers and non-lethal sampling of orchid bee males, we assessed the genetic diversity and population structure of three species, Euglossa pleosticta, Euglossa imperialis, and Eulaema nigrita, collected from forest remnants in the Brazilian savanna biome. Among these species, El. nigrita has being acknowledged as more tolerant to savanic areas, since it is more frequently found in these habitats than the other two species. Thus, we hypothesized that species more associated with forest areas would show lower levels of genetic diversity and higher levels of population structure, since open areas could represent a barrier to the movement of these species. We observed lower levels of genetic diversity (HE) in the species highly associated with forest areas (Eg. pleosticta, HE = 0.66; Eg. imperialis, HE = 0.44) compared to El. nigrita (HE = 0.81). Concerning the genetic structure, it was only remarkable among samples of Eg. pleosticta, a species strongly associated with the forest remnants. Despite the documented dispersal capacity of euglossine bees, maintenance of the connections among forest areas in this biome seems to be critical for their conservation in the Brazilian savanna.