Divergence on the reproductive strategy of two sympatric species of Anthurium (Araceae) in a tropical andean forest

Abstract

The divergence in the reproductive strategy of Anthurium panduriforme and Anthurium caucanum was evaluated based on reproductive phenology, investment patterns in individual and population reproduction, and female reproductive success, along an elevation range between 2200 and 2900 m located in a tropical Andean forest of Antioquia, Colombia. Because both species belong to the same ge-nus, with similar inflorescences in structure, it is possible that they present competition for pollinators. Also, a decrease in reproductive success is expected with an increase in elevation, due to the decrease of abundance of floral visiting insects with elevation. The reproductive individuals of both species were monitored at seven different elevations for one year. The two species studied showed contrasting reproductive strategies: flowering peaks at different times of the year and a greater number of inflo-rescences, infructescences, and reproductive success for A. caucanum compared to A. panduriforme. Inflorescence production and reproductive success for A. panduriforme did not vary significantly along elevation, whereas it decreased for A. caucanum. The floral visitor assemblages differed in composition between species and their abundance in A. panduriforme was significantly higher. The two species studied exhibit contrasting reproductive strategies, which could reduce competition for pollinators, promote seed production and reproductive isolation. This is essential for the maintenance of plant biodiversity while allowing them to coexist syntopically.