FLIES

Horse Flies, Tabanus spp.

Order: Diptera (Flies)

Size: Up to 1"

Habitat: Most habitats near a water source; woodlands, marshes

Range: Throughout North America

Horse flies are related to the deer flies but are generally much larger. Their feeding habits are similar, however, slicing a small incision into the host and sucking out the blood, and they can be a serious pest to livestock. The body is robust with broad, black and green eyes and short, amber-colored, hornlike antennae. The thorax and abdomen are grayish to brownish, with weakly patterned paler areas at each abdominal segment. The wings are mostly clear with dark veins. An egg mass is laid on surfaces above water or on a moist substrate, and larvae feed on larval insects or worms in the soil. Adults are active during the day in the late summer months, and will live for only a matter of days.