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THE MOSQUITOES 



i . Posterior cross vein nearer 

 the base of the wing than 

 the mid-cross vein. 



Dark brown palps with two narrow bands and a white tip. Legs with last three 

 hind tarsal segments white. 



The Megarhinin are of no importance medically. 



The genus Megarhinus has the following characteristics: 



1. Large mosquitoes with brilliant metallic coloring. (Elephant mosquitoes.) 



2. Long, curved proboscis. 



3. Caudal tufts of hairs on each side of abdomen. 



The JEdinae are not known to play any r61e in transmission of diseases. This 

 subfamily is characterized by having the maxillary palpi much shorter in both males 

 and females than the proboscis. 



One genus Sabethes is very characteristic, owing to dense paddle-like scale struc- 

 tures on two or more legs. 



Differentiation of Culicinae Genera 



1. Proboscis curved in female. Psorophora. 



2. Proboscis straight in female. 



A. Palps with three segments in the female. 



(a) Third segment somewhat longer than the 

 first two. Culex. 



(b) The three segments equal in length. Stego- 

 myia. 



B. Palps with four segments in the female. 



(a) Palps shorter than the third of the proboscis. 

 Spotted wings. Theobaldia. 



(b) Palps longer than the third of the proboscis. 

 Irregular scales on wings. Mansonia. 



C. Palps with five segments in the female. Tcenior- 



hynchus. 



2. Posterior cross vein in line with mid-cross vein. Joblotina. 



3. Posterior cross vein further from base of wing than mid-cross vein. Muddus. 



Of the Culicinae the genus Stegomyia is of importance on account 

 of yellow fever. The totally efficient hosts for filariasis (filarial embryos 

 found in the thorax and proboscis) are chiefly among the genus Culex. 

 The genera Mansonia and Taniorhynchus may also transmit filariasis. 

 Some think the Anophelinae genera Cellia and Myzomyia may transmit 

 filariasis as well as malaria. 



The genus Culex is implicated in dengue. 



Stegomyia. This is the most important culicine genus. These are mosquitoes 

 with silver markings. The head, entirely covered with flat scales, has also some 

 upright forked scales. Scutellum has dense flat scales. S. calopus is deep blackish- 

 brown with two thoracic parallel lines with curved silver-white lines outside (lyre 

 marking). Banding of thorax, abdomen, and legs. 



S. calopus bites only at night after the first feeding. The first meal of blood 

 however may be taken in the daytime. To become infected it must take blood 

 from a yellow-fever patient in the first two or three days of the disease. After 

 sucking the blood of a yellow-fever patient the mosquitoes cannot transmit the 





