August, 1944 



Ross: Caddis Flies of Illinois 



229 



This species has been taken in many scat- 

 tered localities in Illinois, almost all of them 

 along fairly large rivers such as the Ohio, 

 Illinois and Kankakee. Our adult emer- 

 gence records run from June 23 to July 14, 

 indicating a single generation per year. The 

 larvae which we are considering as of this 

 species have been taken mainly in large 

 rivers. 



The species is known from adult collec- 

 tions from a limited number of eastern and 

 northcentral states, including Illinois, Ken- 

 tucky, Pennsylvania and Wisconsin; in addi- 

 tion, larvae considered as this species have 

 been taken from Indiana and Minnesota. 



Illinois Records. — Many males and fe- 

 males, taken June 23 to July 21, and many 

 larvae, taken May 4 to October 30, are from 

 Dixon, Elizabethtown (Ohio River), Fox 

 Lake, Hardin, Hoopeston, Kampsville, Kan- 

 kakee, iVIomence, Rockford, Rock Island, 

 Saline Mines (Saline River), Springfield, 

 Sterling, Wilmington. 



Athripsodes tarsi-punctatus (Vorhies) 



Leptocerus tarsi-putictatus \'orhies (1909, p. 

 694); cf . 



Larva. — Length 6 mm. Head brown 

 with indefinite pale spots, fig. 765. Pro- 

 notum and legs straw color to yellowish 

 brown. Parafrons scarcely wider than half 

 width of frons. Pronotum with long, well- 

 separated hairs on anterior margin. Meso- 

 notum with a lateral tuft of 6-8 hairs, 

 mesal portion of tergite with only a few 

 scattered hairs, sclerotized bars thin and 

 gently curved. 



Case. — Length 7 mm., horn shaped, made 

 of vegetable fragments and sand grains, the 

 sand grains predominating in most situa- 

 tions. 



Adults. — Length 11 mm. Color choco- 

 late brown, the base of the tarsi ringed with 

 white. Male genitalia, fig. 780: cerci long, 

 the apex slender; tenth tergite very long, 

 the extreme apex slightly downcurved, a 

 stout sclerotized spur arising from the base 

 and extending three-fourths distance to 

 apex; clasper with a very long basal projec- 

 tion, its apical segment curved, the mesal 

 projection stout and curved. Female geni- 

 talia, fig. 792: ninth sternite with a pair of 

 fingerlike apico-mesal fingers which converge 

 toward apex; bursa copulatrix with lateral 

 bands curved ventrad and convoluted near 



attachment and with only a small triangular 

 sclerite between bursa and dorsal apodeme 

 of tenth tergite, this sclerite sometimes al- 

 most entirely membranous. 



Allotype, female. — Council Hill, Illinois, 

 along Galena River: June 26, 1940, Mohr 

 & Riegel. 



This species occurs throughout the entire 

 state, with a preponderance of records from 

 the northern fourth. The larvae live in 

 lakes and streams. They are abundant in 

 many of the glacial lakes in northeastern 

 Illinois; the streams they frequent are gen- 

 erally fairly clear, rapid and cool. There is 

 usually only one generation a year, the large 

 wave of adults occurring during May and 

 June. 



The species is apparently widespread 

 through the eastern half of the continent, 

 with records available for Arkansas, Geor- 

 gia, Illinois, Indiana, Kentucky, Maine, 

 Michigan, Minnesota, Missouri, New 

 Brunswick, New York, Ontario, Pennsyl- 

 vania, Saskatchewan, South Dakota and 

 Wisconsin. 



Illinois Records. — Many males and fe- 

 males, taken May 4 to August 19, and many 

 larvae, taken May 4 to June 27, are from 

 Amboy ((rreen River), Antioch, Carbon- 

 dale, Channel Lake, Charleston, Chicago, 

 Council Hill (Galena River), Dixon, East 

 Fox Lake, Elgin (Rainbow Springs), Fox 

 Lake, Grand Tower, Harrisburg, Havana 

 (Quiver Creek), Johnsburg (Fox River), 

 Kankakee, McHenry, Mineola (East Fox 

 Lake), Momence, Ottawa, Pistakee Lake, 

 Rock Island, Rosecrans (Des Plaines Riv- 

 er), Savanna, Serena (Indian Creek), 

 Shawneetown, Springfield, Spring Grove 

 (Nippersink Creek), Sterling, Urbana, 

 Wadsworth (Des Plaines River), West Fox 

 Lake, Wilmington, Zion (Dead River). 



Athripsodes alagmus Ross 

 Athripsodes alagmus Ross (1938rt, p. 155); 



Larva. — Fig. 764. Length 7 mm. Head 

 brown with definite pale spots which do not 

 contrast greatly with the background. Pro- 

 notum and legs straw color to yellowish 

 brown. Frons and other structural charac- 

 ters similar to those of tarsi-punctatus. 



Case. — Length 8 mm., horn shaped, made 

 chiefly of vegetable fragments, very rarely 

 with some sand grains mixed with these. 



Adults. — Length 12 mm. Color choco- 



