THE FLIES THAT CAUSE MYIASIS IN MAX 163 



abdomen is dark brown, often appearing- black in dried specimens ; its ventral 

 surface is light yellow. Larva (fig. 98) : Color, yellowish white. The head has 

 the usual hooks. Each body segment is provided with six pairs of hairy, fleshy 

 processes which gradually increase in length toward the posterior segments ; the 

 processes at the sides are long, the Longest being definitely longer than the humps 

 bearing the posterior spiracles. 



Geographical Distribution. — Nearctic Region : Alaska, Labrador, Quebec, 

 Ontario, Alberta. British Columbia. Maine, New Hampshire, Vermont, Massa- 

 chusetts, Connecticut, New York. New Jersey. Pennsylvania. Maryland, District 

 of Columbia. Florida. Michigan. Illinois. Kentucky, Minnesota, Idaho, Colorado, 

 New Mexico, Washington, Oregon. California. Neotropical Region: Brazil, 

 Chile, Argentina, Patagonia. Palaearctic Region : Scotland, England, Spain, 

 France. Netherlands, Belgium, Switzerland, Italy, Corsica. Norway. Sweden, 

 Finland, Estonia, Denmark. Austria. Hungary, Yugoslavia, Rumania, European 

 Russia (Arkhangelsk;, Canary Islands, Madeira. Tunisia. Libia, Siberia. Ori- 

 ental Region: India. Ethiopian Region: South Africa (Mossel Bay). Wide- 

 spread and very common in Europe and North America. 



Pathogenesis. — Pattern has recorded two cases of wound myiasis in 

 cattle in India caused by this species, one of them in association with 



? ? 



Figure 98. — Megaselia rufipes, larva, side view. 



Megaselia sections. It may easily be a human parasite at times. Sup- 

 posed cases of intestinal myiasis have been recorded, but evidence 

 is not conclusive. 



The Family LARVAEVORIDAE (Tachinidae) 



The Tachina Flies 



The family Larvaevoridae. in the broad but not the broadest sense — 

 that is, to include the Dexiidae. Prosenidae, etc.. but to exclude such 

 families as the Oestridae. Calliphoridae, and Sarcophagidae — may. 

 for practical purposes, be readily distinguished from other calypterate 

 muscoids by having at least moderately well-developed mouth parts, 

 a well-developed postscutellum, vein m 1 _ 2 strongly bent forward so as 

 to narrow or close the apical cell, and hypopleural bristles present. 

 Some species of comparatively rare occurrence will not conform to 

 the above diagnosis. The family is a large one. with a great many 

 genera and species. The larvae are usually parasitic on other insects. 

 The one record of human myiasis is very surprising. 



The Genus MI1VTHO Robineau-Desvoidy 

 MINTHO ALGIRA (Macquart) 



Synonym. — Mintho praeceps var. algira (Macquart). 



No attempt will he made to give the distinguishing characteristics of the 

 genus or species; determinations in this family should be made by a specialist 



In general the fly is black, with considerable silvery pollen on the head and 

 thorax; the abdomen is reddish yellow, with a median black vitta of varying 

 form and width: the legs are yellowish, the tarsi becoming black: the general 

 body form is elongated; length 0-12 mm. Onorato's illustration is sketchy 



