August, 1944 



Ross: Caddis Flies of Illinois 



199 



Fig. 689. — Frenesia missa 9. 



This species is distinguished from the 

 others in the genus by characters given in 

 the preceding key. It is represented only by 

 the single collection of the type series. Con- 

 sidering the frequency with which the larvae 

 are found, and the few records of the 

 adults, there is every indication that we 

 may have in this genus a more extensive 

 fauna than has hitherto been considered. 

 All our records for Illinois and Indiana 

 were taken in September and October, a 

 time when little general collecting is done 

 for this order. 



Chilostigma McLachlan 



Chilostigma McLachlan (1876, p. 187). 

 Genotype, monobasic: Chilostigma sieboldi 

 McLachlan. 



There is only one North American spe- 

 cies in the genus, areolatum, described from 

 "Arctic America," with records from On- 

 tario and Labrador. It has never been 

 taken in Illinois. 



Frenesia Betten & Mosely 



Frenesia Betten & Mosely (1940, p. 165). 

 Genotype, by original designation: Limne- 

 philus difficilis Walker. 



Of the two North American species, only 

 missa has been found in Illinois. The other 

 species, difficilis, is eastern in distribution. 



Frenesia missa (Milne) 



Chilostigma missum Milne (1935, p. 35); 

 cf, 9. 



Larva. — Length 11 mm. Head, thoracic 

 sclerites and legs reddish brown, the head 

 with only very indistinct lighter spots, the 

 legs slightly lighter than the head. Pro- 



notum with only a very indistinct trans- 

 verse groove. 



Case. — Length 12 mm., constructed of 

 small stones; slender, cylindrical and fairly 

 rigid. 



Adults. — Fig. 689. Length 13-14 mm. 

 Head and body varying from almost black 

 to various shades of brown; legs beyond 

 coxae yellowish brown; wings with a ground 

 color of brown with small, translucent dots 

 scattered uniformly and abundantly over the 

 entire surface, giving it a salt-and-pepper 



Fig. 690. — Frenesia missa, male genitalia. 



Fig. 691. — Frenesia missa, female genitalia. 

 A, ventral aspect; B, lateral aspect. 



