BITING FLIES 



3 OI 



In the Muscidae the antennae hang down in front of the head in three segments 

 and have an arista plumose to the tip. The first posterior cell is narrowed. There 

 are no bristles on abdomen except at tip. 



(I) Stomoxys, Haematobia and Glossina have a more or less 

 elongated proboscis adapted for biting. Stomoxys has delicate palpi, 

 shorter than the proboscis, and arista feathered only on the dorsal side 

 with straight hairs. Haematobia has club-like palpi about as long as 

 proboscis and arista with hairs dorsally and ventrally. Glossina has 

 thick set but not clubbed palpi and an arista feathered on the dorsal 

 side with branching hairs. 



(II) Musca, Calliphora, Chrysomyia, Lucilia, and Cordylobia do 

 not have a proboscis adapted for biting. 



FIG. 85. Common housefly (Musca domestica): Puparium at left; adult next, 

 larva and enlarged parts at right. All enlarged. From circular 71 (by L. O. 

 Howard), Bureau of Entomology, U. S. Department of Agriculture. 



Stomoxys calcitrans. These greatly resemble the common housefly in size 

 and shape. They can be easily distinguished by the black, piercing proboscis extend- 

 ing beyond the head. There are longitudinal stripes on the thorax and spots on the 

 abdomen. The proboscis on examination will be seen to be bent at an angle near its 

 base. The palps are short and slender. The wings diverge widely. 



The female lays about 60 banana-shaped eggs in horse manure. These hatch 

 out in three days as larvae which turn into pupae in two or three weeks. After about 

 ten days the fly emerges. The genus Stomoxys includes vicious biters. This is 

 the fly which comes into houses before a rain, and which has given the common house- 

 fly the reputation of biting before a rain. Stomoxys may be implicated in trans- 

 mitting surra (Trypanosoma evansi). 



It has now assumed great importance as a transmitter of poliomye- 

 litis and possibly of pellagra. 



