Pollination of Nymphaea lotus (Nymphaeaceae) by Rhinoceros Beetles and Bees in the Northeastern Ivory Coast

Detailed observations of the pollination biology of Nymphaea lotus were conducted by studying populations growing in seasonal ponds in the Comoé National Park (NE Ivory Coast). Flowers of N. lotus are protogynous and anthesis lasts for 4 to 5 days. Flowers open at sunset and close in the morning hours, thereby revealing a high variability in timing. For the first time, heat production in flowers could be observed in the genus Nymphaea. Flowers of N. lotus were visited by Ruteloryctes morio, an endemic dynastid beetle during the night. Beetles copulated in the flowers and fed on flower parts, but were less effective pollinators than several bee species that visited flowers in the early morning. Nymphaea lotus thus seems to be adapted to pollination by both nocturnal beetles and diurnal bees.