KINGDOM: Animalia | PHYLUM: Arthropoda | CLASS: Insecta | ORDER :Diptera | FAMILY: Syrphidae (flower flies, hover flies, drone flies)

Immature flower flies are legless and wormlike, and, like most fly larvae, are very difficult to identify, even for experts. They are seldom encountered.

Like all flies, flower flies have complete metamorphosis with egg, larval, pupal, and adult stages.  The larvae are legless and wormlike. Winged adults are active during warm months.  Most species overwinter as pupae in soil or under fallen leaves.

Most flower flies are not considered pests.  The species that resemble bees are not able to sting or bite, although sometimes they will land on humans to gather moisture in the form of sweat droplets.  Many species of flower flies are considered beneficial because their larvae feed on aphids and other pests.

The larvae of a few species of drone flies, called "rat-tailed maggots," are occasional pests in livestock operations.  Some drone fly larvae have also been known to cause intestinal myiasis in humans, but this is very rare in the United States.

Read more about rat-tailed maggots in our online ENTFact:
www.uky.edu/Agriculture/Entomology/entfacts/livestc/ef500.htm

HOVER FLIES
GENUS: Metasyrphus, others
Most of the flower flies that live in Kentucky are commonly called "Hover Flies."  These flies are able to hover in mid-air, much like hummingbirds.  There are many species of hover flies in Kentucky. Many of them resemble bees and wasps and are found in weedy habitats and gardens.  Small black and yellow hover flies are very common around homes.  The larvae of several flower fly species are predators of aphids and other small insects (one is pictured in the Ecology section above).

Flower flies are easy to find during the summer in Kentucky.  Look for them in gardens and in weedy areas, or anyplace else where wild or cultivated flowers grow.  Flower flies are able to hover in place and are accurate fliers, so it is sometimes a challenge to capture one with a sweep net.  They will often remain still on a flower for a few moments, though, creating a good opportunity for a photograph.

Larval flower flies and rattailed maggots can be more difficult to find.  Look for predatory syrphid larvae on certain crop plants (like tobacco) that are frequented by aphid pests.  Rattailed maggots are fairly common in silage ponds and other polluted water sources, but these areas are not a safe place to collect insects.

Some flower fly larvae are important predators of aphids and other pests.  Read more about their importance at these websites:

Beneficial flower flies in California:
http://www.ipm.ucdavis.edu/PMG/NE/syrphid_flies.html

Flower flies are often called "sweat bees" because of their resemblance to bees and because they often land on human skin to gather sweat.  Flower flies cannot sting, but there are small black bees in the family Halictidae (also commonly called sweat bees) that will occasionally sting humans while they are gathering sweat.  Often, the innocent flower fly is been blamed for some of the stings caused by "true" sweat bees.