Prestoea palm flower visitors and potential pollinators in the Andean–Amazonian Piedmont Forest of Ecuador

Abstract

The palms Prestoea acuminata and P. schultzeana are found at altitudes between 800 and 2600 m asl. and 200 and 1300 m asl., respectively. Although they are important components in the dynamics of the Andean–Amazon transition forest, and are used by local communities, there is not enough biological information that explain their strategies for reproductive dynamics and its conservation. In order to contribute to the knowledge of the reproductive biology of these species we studied the diversity of flower visitors and pollinators of each one, the differences between the pistillate and staminate phases and the species shared between them. The study was carried out in the Piedmont evergreen forest and the Napo low evergreen forest of Ecuador. We collected 15 inflorescences of P. acuminata and 9 of P. schultzeana. We then divided the flower visitors into morphospecies and counted, photographed and identified them to the best possible taxonomic level. We counted 10,123 flower visitors from 82 morphospecies in P. acuminata and 1192 from 42 morphospecies in P. schultzeana. Based on abundance and frequency of morphospecies, and observations of pollen in the pistillate phase, we found six potential pollinators in P. acuminata, all Coleoptera, and five in P. schultzeana, three Coleoptera and two Diptera, suggesting the cantharophily syndrome of the former and the myophily of the latter. The palm species shared only one morphospecies of Aleocharinae (Coleoptera, Staphylinidae), showing that flower visitors are very specific to each palm and their importance in maintaining insect diversity in these forests.