FAMILY MUSCIDAE 
HOUSE FLIES, STABLE FLIES, AND ALLIES 
Flies of this family vary in length from 2 to 12 mm. Some are 
yellowish or black in color, but the majority are gray or brown. 
There are several economically important species, such as the 
well-known house fly, Musca domestica L., the stable fiy, Stomoxys 
Haemetobia irritans (F.), and the tsetse flies. Fortunately, 
tsetse flies, which transmit the organisms responsible for sleeping 
sickness and other diseases, are native to Africa and do not occur 
in this country. A number of svecies in the genus Muscina are 
parasites of various species of Coleoptera. 
FAMILY HIPPOBOSCIDAE 
LOUSE FLIES 
Louse flies may be winged or wingless. Many look like lice. The 
body is flat and leathery-looking, and the legs are short, strong, 
and broadly separated by the sternum. The tarsi are short and 
armed with strong claws, and the abdomen is saclike. All species 
feed on birds and mammals. The best known member of the 
family is the sheep ked, Melophagus ovinus (L.), an important 
parasite of sheep. Other important species are Lynchia americana 
(Leach) —parasitizes grouse, hawks, and owls; Olfersia fumi- 
pennis (Sahl.)—attacks the bald eagle; species of Ornithoica and 
Ornithomyia—feed on various small birds; and species of Lipop- 
tena—parasitize deer. 
FAMILY CALLIPHORIDAE 
THE BLOW FLIES 
Blow flies have metallic blue, green, or yellow bodies and are 
usually about the size of house flies. The arista of the antenna is 
plumose at the tip and the hindmost posthumeral bristle is almost 
always longer than the presutural bristle. In the maggots, or 
larvae, the posterior spiracles are flush. A few species are eco- 
nomic pests, but the majority serve a useful purpose in helping to 
rid the landscape of such undesirable materials as dead animal 
bodies and animal excrement. 
The screw-worm, Cochliomyia hominivorax (Coquerel), a long 
time pest of livestock in the Southwest, was first recorded from 
the Southeastern States in 1933. Since then, or until its eradica- 
tion from the region through the mass release of sexually sterile 
male flies (457), it caused tremendous losses to livestock. Big 
game, such as deer, and smaller animals, such as racoons, rabbits, 
and opossums, have also been attacked and injured. The female 
deposits up to 300 eggs around wounds; the maggots feed on the 
tissues, and produce foul smelling wounds. This attracts addi- 
tional flies and compounds the infestation. Heavily infested ani- 
mals may die within a few weeks unless the maggots are killed 
and the wounds treated. 
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