on the shores of ponds and lakes. The flies range in length from | to about 15 mm 
and probably are all predatory, mostly on small Diptera. The larvae live in damp 
earth, in decaying wood or other vegetation, under the bark of trees, or in the water. 
Tachydromia sp. has been reared from eastern white pine leaders infested with the 
white pine weevil. 
Family Dolichopodidae 
Longlegged Flies 
Members of this family are very small, longlegged flies, rarely more than 10 mm 
long. Adults are predacious on other insects and are found on the foliage or trunks 
of trees, or on damp earth, usually in swamps or along lightly shaded streams. Most 
of the larvae appear to be aquatic, but those of a few species occur under the bark of 
trees where they feed on other insects. Dolichopus vittatus Loew has been reared 
from beetle-infested hickory, and Medetera sp. from beetle-infested larch and pine. 
Family Pipunculidae 
Bigheaded Flies 
Pipunculids are small, dark flies with large heads composed mostly of large, 
approximated eyes. The larvae are small, elliptical, thick, depressed, naked, and 
narrowed at each end. They are parasitic on various families of Homoptera, 
especially the Cicadellidae. 
Family Syrphidae 
Flower Flies 
This is one of the largest families in the order Diptera, and it is almost entirely 
beneficial (840, 1342). The adults are strongly attracted to flowers and play 
important roles in the cross-pollination of plants and trees. The larvae of many 
species feed on and aid in control of many destructive insects such as aphids, 
scales, psyllids, spittlebugs, mealybugs, and lepidopterous larvae. A few species 
are plant feeders but they are seldom injurious. 
Adults are usually brightly colored and are frequently striped, spotted, or banded 
with yellow. Some resemble wasps; others look like small bumble bees. The maies 
have the peculiar habit of hovering almost completely motionless in the air and then 
darting swiftly to one side when disturbed. The maggots of insect-feeding species 
are Sluglike. The body tapers toward the front end and the body contents are visible 
through the integument. 
Family Conopidae 
Thickheaded Flies 
Conopid flies are thinly pilose or nearly bare, elongate, and of moderate size. 
The head is broader than the thorax, and the abdomen is elongated and constricted. 
The antennae are three-segmented, the third segment bearing a dorsal arista. Adults 
fly slowly and are usually seen around flowers. The larvae are solitary internal 
parasites, mainly of Hymenoptera. One species parasitizes grasshoppers and 
crickets. 
Family Tephritidae 
Fruit Flies 
Fruit flies are fairly small and usually have spotted or banded wings. The larvae 
are usually pale yellowish and taper slightly toward the front. Eggs of most species 
are deposited in healthy, living tissue and larvae feed in various parts of plants. 
Certain species produce root and stem galls and a few are leafminers. Others 
develop in fleshy fruits or in the seeds or ovaries of flowers. Many species are 
highly destructive of fleshy fruits and vegetables throughout the world. A few of the 
species occurring in the woodlands or forests of the Eastern United States are 
discussed below. 
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