Pest Status: Syrphid flies are not considered pests. They cannot sting people.
Appearance: Adults have black and yellow bands on their abdomens and are often mistaken for honey bees or wasps. The body length ranges from 1/4 to 3/4-inch long. Unlike bees and wasps, they have just one pair of wings, short antennae and big, compound eyes.
Life Cycle: A female oviposits a single egg on a leaf near an aphid infestation. The larva hatches in about three days, and as it feeds on aphids it develops through several instars over two to three weeks before pupating. The adult emerges in one to two weeks unless the pupal stage remains throughout the winter.
Where to Collect: Syrphid flies are especially common where aphids are present in agricultural, landscape, and garden habitats.
Purdue Extension Entomology, 901 West State Street, West Lafayette, IN 47907 USA, (765) 494-4554