The ecology of the flowers of the savanna tree Maranthes polyandra and their visitors, with particular reference to bats

Nocturnal observations were made on M. polyandra (Chrysobalanaceae), a common tree in the Guinea Savanna zone of West Africa, which shows many adaptations for pollination by bats. The flowers are borne on stiff pedicels in large white inflorescences, and each flower lasts for only 1 night. The anthers release pollen from about 19.30 h, and the stigma matures at about 01.00 h; nectar production is copious. The flowers are produced in the wet season when few other plants are flowering. The small bat Nanonycteris veldkampi (Pteropinae: Megachiroptera) visited the trees frequently for nectar. Feeding visits were sporadic soon after dusk, but became increasingly frequent until about 21.30 h, after which very frequent visits were observed until dawn. Analysis of the pollen loads of 29 bats showed that Protea elliottii is visited frequently in addition to M. polyandra. The bats probably travel several kilometres during the night. No evidence was obtained for the bats feeding on anything except nectar. Various other visitors, such as small insects, hawkmoths, genets and several bird species, feed on the nectar or pollen.