August, 1944 



Ross: Caddis Flies of Illinois 



195 



Larv'a. — Length 18-20 mm. Head, tho- 

 racic sclerites and legs shades of reddish 

 brown; head and pronotum with abundant 

 small dark brown dots ; legs with tibiae and 

 tarsi darker and redder than preceding seg- 

 ments. Gills very long and single. First 

 abdominal segment with a pair of very small 

 sclerites near meson of venter and with only 

 a few scattered setae on the rest of the 

 venter and on the dorsum. Pronotum with 

 distinct and fairly deep transverse furrow. 



Case. — Length 20 mm. Constructed of 

 stones, sand and wood fragments; robust 

 and straight, frequently with a long twig 

 or a group of small twigs cemented to the 

 sides so that they trail behind the case ; the 

 variety of materials used varies from place 

 to place, sometimes the stone material pre- 

 dominating, sometimes the wood fragment 

 material, so that there is great variation in 

 the general appearance of the case. 



Adults. — Length 19-20 mm. Color 

 brown, front wings usually with two dark 

 brown marks, a transverse one which ends 

 just in front of m-cu, and a more or less 

 angulate mark along the cord; in addition 

 the apex of the wing and a narrow border 

 along the tips of the veins are darkened. 

 Male with eighth tergite rounded at apex 

 and bearing a pair of triangular areas cov- 

 ered with short, brown spines, fig. 675. 

 Male genitalia, fig. 675, with claspers pro- 

 duced into a long dorsal process which usu- 

 ally has a low lateral shoulder at its base; 

 tenth tergite with mesal processes fairly 

 long; aedeagus elongate with a pair of long, 

 needle-like dorsal styles, each of which has 

 a long, tubular base. Female genitalia, fig. 

 682: tenth segment with lateral flangelike 

 expansions on dorsal portion, ventral portion 

 wide and emarglnate on meson, the apical 

 opening wide; subgenital plate and bursa 

 copulatrix as in Hg. 682. 



Neotype, male. ^ — McHenry, Illinois: 

 Oct. 4, 1931, Ross & Mohr. 



This species is very abundant in scattered 

 localities in the state, especially in the north- 

 ern and eastern parts. It occurs in such 

 rivers as the Salt Fork and Kankakee and 

 also in the glacial lakes in the northeastern 

 corner. There is only a single generation 

 per year. In this state the larvae become 

 full grown not later than June, then aesti- 

 vate until September, when the adults 

 emerge. In localities to the north, adult 

 emergence may take place in August, as in 

 Neophylax. 



This species is widespread through the 

 Northeast; records are available for Illi- 

 nois, Michigan, Minnesota, New York, 

 Pennsylvania, South Dakota and Wisconsin. 



Illinois Records. — Channel Lake: 

 May 16, 1936, Ross & Mohr, many larvae; 

 May 27, 1936, H. H. Ross, 2 larvae. Fox 

 Lake: Sept. 22, 1931, Prison & Ross, S $ . 

 Golconda: April 17, 1930, Prison & Ross, 



1 larva. Havana: June 16, 1894, C. A. 

 Hart, 4 larvae; Sept. 21, 1894, C. A. Hart, 



2 pupae; April 9, 1895, 2 larvae; Quiver 

 Creek, April 29, 1937, Ross & Mohr, 1 $ , 

 19,2 larvae. Homer: Sept. 24, 1927, T. 

 H. Prison, 1 9. Kankakee: June 6, 1935, 

 Ross & Mohr, 1 larva. Kankakee Coun- 

 ty, Kankakee River: June 1, 1901, Laske 

 & Wright, 4 larvae. McHenry: Oct. 4, 

 1931, Ross & Mohr, $ $ . Momence: Sept. 

 19, 1937, Ross & Burks, many larvae and 

 pupae, 6 S, 9 9 (all reared), 1^ ; Kan- 

 kakee River, May 26, 1936, H. H. Ross, 3 

 larvae; July 14, 1936, B. D. Burks, 1 larva; 

 Aug. 21, 1936, Ross & Burks, 2 larvae; 

 Sept. 17, 1937, B. D. Burks, 7 larvae, many 

 pupae, 1 9 ; Sept. 20, 1937, Ross & Burks, 



3 larvae; Kankakee River, Oct. 4, 1937, 

 Ross & Burks, 2 9 . Wilmington, Kanka- 

 kee River: May 17, 1935, H. H. Ross, 1 

 larva. 



Pycnopsyche lepida (Hagen) 

 Enoicyla lepida Hagen (1861, p. 269); cf. 



Larva and Case. — Similar to those of 

 subfasciata. 



Adults. — In size and color similar to 

 subfasciata. Pighth tergite of male with 

 posterior margin sharply incised and with 

 a brush of black setae along entire margin. 

 Male genitalia, fig. 673, differing from those 

 of subfasciata chiefly in always having a 

 large, sharp, concave shoulder at the base 

 of the apical process of the claspers. Fe- 

 male unknown; the specimen so labeled by 

 Betten & Mosely (1940, p. 156) is only a 

 provisional assignment as stated by the au- 

 thors, and we have no well-associated fe- 

 males for the species. 



We have only a single record of this spe- 

 cies from Illinois, a male collected along the 

 Kankakee River at Momence, September 7, 

 1937, Prison & Ross. Apparently its life 

 cycle is the same as for subfasciata. 



The range of the species is very similar 

 to that of subfasciata: through the North- 



