Foraging Behavior and Pollen Transport by Flower Visitors of the Madeira Island Endemic .

The study of flower visitor behavior and pollen transport dynamics within and between plants can be of great importance, especially for threatened or rare plant species. In this work, we aim to assess the flower visitor assemblage of the Madeiran endemic and evaluate the performance of the most common visitors through the analysis of their foraging behavior and pollen loads. The flower visitor assemblage of is diverse, including several insect groups and the endemic lizard , but bees are the most common visitors. In general, large bees (, , and spp.) had the highest average visitation rates (>18 flowers/min) and their pollen loads had higher percentages of homospecific pollen (>66%) when compared with butterflies and hoverflies. The honeybee () and two bumblebees ( and ) were the most efficient flower visitors of , but their foraging behavior seems to favor geitonogamy. Other visitors, such as butterflies and the small bee , may have a complementary role to the honeybee and bumblebee species, as their high mobility is associated with fewer flower visits on each plant and may promote xenogamy. Two non-native bees ( and ) are important flower visitors of and may contribute mostly to self-pollination rendering the endemic plant more vulnerable to inbreeding effects.