Pollinators of syntopic Marcgravia species in Costa Rican lowland rain forest: Bats and opossums

The visitors of four syntopically occurring species of Marcgravia (M. nervo sa, M. serrae, M. mexicana, and M. nepenthoides) in the Atlantic lowland ra in forest at La Selva Biological Station in Costa Rica were observed. The f our species differed in flowering phenology and morphology of inflorescence s. Flowers of all species opened during the night and the stamens dropped b efore dawn. All species were visited by small nectar-feeding bats (Phyllost omidae: Glossophaginae). Marcgravia nepenthoides, with much larger nectarie s, additionally attracted two species of opossums, Coluromys derbianus and Didelphis marsupialis. Judging from the large distance between nectaries an d flowers, glossophagine bats probably are inefficient pollinators of this species, and merely exploit a non-flying mammal pollination system.