Oilflowes and their bee guild in a tropical restinga community

Abstract

Centridini is a very diversified oilbee group in the open vegetation habitats of coastal restinga, where it represents 20% of all bee species and 50% of bee individuals sampled on melittophilous flowers. This oilbee guild is packed in Byrsonima sericea (Malpighiaceae) flowers, its single oil source in this plant community. B. sericea is a self-incompatible species that relies mainly on Centridini bees for cross-pollination, therefore, the high population density of B. sericea (65 indiv/ha) in the restinga might be related with the high local abundance of Centridini bees and vice-versa. This statement is indirectly supported by the positive relationship between diversity measures of Centridini and Malpighiaceae in the surrounding lowlands. Anyway, to explain the high diversity of Centridini in the restinga, the abundance of oilflowers might be more important than richness of oilflowers. These rich oil patches release population growth of the Centridini bees, and they should play a central role for planning in situ biological conservation in the patchy restinga landscape.