August, 1944 



Ross: Caddis Flies of Illinois 



35 



dorsal portion is low and rounded 

 instead of forming a distinct heel. . 

 kiamichi, p. 37 



7. Apical segment of clasper with a mesal, 



setose flap; arms of aedeagus at 

 apex with several stout spines, each 

 surrounded by smaller setae, fig. 



126 fenestra, p. 36 



Apical segment of clasper without a 

 mesal flap; arms of aedeagus with a 

 brush of setae of almost equal size, 

 fig. 127 ledra, p. 37 



8. Eighth segment with apex of sternite 



deeply excavated and apex of tergite 

 bi-emarginate, fig. 132. . .fuscula, p. 36 

 Eighth segment neither with sternite 

 deeply incised nor with tergite bi- 

 emarginate 9 



9. Apex of eighth sternite with a pro- 



duced mesal plate which is differen- 

 tiated in texture from remainder of 

 segment, fig. 129; tenth tergite 

 sclerotized and spined, fig. 129. .. . 



lobifera, p. 35 



Eighth sternite without such a plate; 

 tenth tergite chiefly membranous, 

 without spines, fig. 128 10 



10. Eighth sternite short and stout, venter 



distinctly bulged near base, fig. 128 



vibox, p. 36 



Eighth sternite longer and more 

 slender, without ventro-basal bulge, 

 fig. 130 11 



11. Eighth tergite with an apical incision, 



fig. 131; entire segment with only 

 moderately long hair; size larger, 



10 mm. or more 



fenestra, p. 36; ledra, p. 37 



Eighth tergite without a marked in- 

 cision, fig. 130; entire segment 

 clothed with long hair; size smaller, 

 8 mm. or less glaberrima, p. 35 



Rhyacophila lobifera Betten 



Rhyacophila lobifera Betten (1934, p. 131); 

 cf , 9, larva. 



Larva. — Length 15 mm.; head and pro- 

 notal shield straw color, with scattered 

 brown dots; body greenish. 



Adults. — Length 11-13 mm.; color dark 

 bluish gray, with some yellowish patches of 

 hair on head, body and wings. Legs yellow 

 to greenish. Male genitalia, fig. 120, with 

 claspers very long, the apical segment in- 

 cised to form a sharp dorsal point; tenth 

 tergite large and somewhat triangular. Fe- 

 male genitalia as in fig. 129 (note the inter- 

 segmental folds, i./., between segments 8 

 and 9). 



This species at times has been considered 

 a synonym of montana Carpenter, described 

 from the Great Smoky Mountains of North 

 Carolina, but the two differ radically in the 

 shape of the tenth tergite. That of montana 

 has long, slender, sclerotized processes, fig. 

 121, and that of lobifera comprises a single, 

 stout, triangular protuberance. 



Originally described from Lake Bluff, 

 Illinois, lobifera has since been taken in 

 widely scattered localities in the state, prin- 

 cipally in the eastern portion. It frequents 

 small, rapid, clear streams that are of a 

 temporary nature in drought years. The 

 adults appear during April and May in 

 southern Illinois and during May and June 

 in northern Illinois. 



Known also from Indiana, Ohio, Okla- 

 homa. 



Illinois Records. — Many males, females 

 and pupae, taken April 3 to June 3, and 

 many larvae and cases, taken March 5 to 

 May 1, are from Alto Pass (Union Spring 

 Creek), Brockton (Catfish Creek), Car- 

 bondale (Clay Lick Creek), Dixon Springs, 

 Eddyville (Eddy Creek), Filson, Fox Ridge 

 State Park, Grayville, Harrisburg (Black- 

 man Creek), Herod (Gibbons Creek), Hill 

 (tributary of Bishop Creek), Hurd (small 

 stream), Marshall, Mazon (Mazon Creek), 

 Muncie (Stony Creek), New Columbia 

 (Clifty Creek), Oakwood (West Branch), 

 Red Bud, Ritchie (small stream), Rose- 

 crans, St. Elmo (South Fork Creek), To- 

 ledo, Tuscola, Urbana, Waltersburg, Wat- 

 son, Willow Springs. 



Rhyacophila glaberrima Ulmer 



Rhyacophila glaberrima Ulmer (1907^, p. 

 85); cf. 



Rhyacophila fairchildi Banks fl930fl, p. 

 130); d^. 



Rhyacophila andrea Betten (1934, p. 127); 



Larva. — Length 12 mm. Body long and 

 slender. Head, pronotum, legs and anal 

 sclerites light yellow with suffused brown 

 markings. Anal hooks stout, each with one 

 large and one small inner tooth. 



Adults. — Length y-S mm. Head and 

 body dark brown; legs pale, slightly green- 

 ish; wings dark, without pattern. Male 

 genitalia, fig. 123, with tenth tergite pro- 

 jecting; claspers very long, and with curious 

 "forks" at apex of lateral appendages of 

 aedeagus. Female genitalia, fig. 130, with 



