The Role of Flower Visitors in the Explosive Pollination of Thalia geniculata (Marantaceae), a Costa Rican Marsh Plant

Abstract

are common flower visitors to a population of Thalia geniculata (Marantaceae), located in the Palo Verde Wildlife Refuge, Guanacaste Province, Costa Rica. In this study, the role of these pollinators in triggering the explosive pollination mechanism of Thalia was assessed and visitation rates were recorded in three successive years. Bees were found to trigger most flowers they visited, hummingbirds triggered approximately 50% of visited flowers, and butterflies did not trigger any. Visitation activity at flowers varied significantly in both space and time, and was influenced by flower height, a plant's proximity to other conspecifics, the strength of the wind (which varied daily) and possibly by the flowering state of other species growing nearby (which varied annually). T. geniculata was found to be able to produce seeds autogamously which prevents reduction in seed set in areas, or during periods, of low pollinator activity.