The Biological Flora of Coastal Dunes and Wetlands. 2. Ipomoea pes-caprae (L.) Roth

Ipomoea pes-caprae (L.) Roth (railroad vine) is a pantropical, perennial, trailing vine (Convolvulaceae) with showy pink flowers that grows on coastal beaches and dunes throughout the tropical and subtropical areas of the world. Here I present a summary of ecological, physiological and geomorphological aspects of the biology of I. pes-caprae. Its success as a colonizer of tropical shorelines may he attributed to the production of large numbers of fruits, long life cycle, high potential for water dispersal, resistance to salt spray, rapid growth, large neighborhood size, and vegetative reproduction. The species is important as a sand colonizer and plays a significant role in geomorphology. The plants often cover large areas and form a rather continuous mat that helps to keep the sand from moving and holds the substrate together. The flowers are visited by bees and other insects; Xylocopa species (Hymenoptera) are important pollinators. Ants visit extrafloral nectaries and help the plant increase reproductive success in some areas. The leaves and seeds contain the indole alkaloid ergotamine, which protects them from many herbivores. Flowers are sometimes eaten by herbivores, and a beetle (Megacerus leucospilus) parasitizes the seeds.