XVI International Botanical Congess

The average natural fruit production was studied in a population of Encyclia phoenicea. Only 16.1% of the flowers were visited by the potential pollinator and 4.1% were effectively pollinated. Twelve potential pollinators visited the flowers, but only the bee Xylocopa cubaecola was effective. A study of the morphology and behavior of the bee may be evidence that the floral characteristics of E. phoenicea have evolved as a result of an evolutionary interaction with the bee. Fruit iniciation was 3.9% and fruit maturation was 1.4%. Fruit set is low in comparison with reports of other tropical orchids. Infrequency of effective pollinator visits was, however, the most important factor in limitation of fruit production. The pollination mechanism is described.