Hover fly. Close-up of a hover fly pollinating a flower of the American Plum (Prunus sp.). Many hover flies (family: Syrphidae) resemble the stinging Hymenoptera such as wasps and bees. This mimicry is designed to prevent the insect being attacked or eaten. Hover flies chiefly eat pollen and nectar (as here), and play a major role in pollination, carrying pollen from flower to flower. These insects are named for their hovering ability. They beat their wings extremely fast to achieve stationary flight. Unlike the bees and wasps they mimic, hover flies have no sting and are not as unpleasant to eat. Photographed in the Valentine National Wildlife Refuge, Nebraska, USA.