EXPLOITATION OF MABEA-FISTULIFERA NECTAR BY MARMOSETS (CALLITHRIX-FLAVICEPS) AND MURIQUIS (BRACHYTELES-ARACHNOIDES) IN SOUTH-EAST BRAZIL

The present study reports on the exploitation of the nectar of Mabea fistulifera (Euphorbiaceae) by two platyrrhine primate species (Brachyteles arachnoides and Callithrix flaviceps) in the Atlantic Forest of south-east Brazil. Nectar-feeding by both primates was observed between late April and May, during which a peak in the floristic activity of M. fistulifera was recorded, in terms of both the number of trees flowering and the number of flowers available on each tree. Phenological records indicate, by contrast, that edible fruit was relatively scarce during this period, the early dry season at the study site. On the days when nectar was consumed, it accounted for 25% of records of plant feeding for B. arachnoides and 29% for C. flaviceps, although the former species was observed nectar feeding over a much longer period. The evidence indicates that M. fistulifera is a valuable, but not essential resource for both primates at a time of year when edible fruit is relatively difficult to obtain. M.fistulifera, in turn, can be seen as an opportunistic plant whose floral characteristics permit pollination by a wide range of volant and non-volant vertebrates, including primates.