102 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



Mohr, 1 S (reared) ; June 6, 1935, Ross 

 & Alohr, 6 S, 9 9; July 21, 1935, Ross 

 & Mohr, S $ ; Aug. 8, 1935, Ross & De- 

 Long, \$, 19, 4 larvae; May 17, 1937, 

 Ross & Burks, $ $, 5 $ ; May 6, 1938, 

 Ross & Burks, 1 $ ; May 31, 1938, Mohr 

 & Burks, 1 $ ; June 29, 1939, Burks & 

 Ayars, 1^. Momence: Kankakee River, 

 May 26, 1936, H. H. Ross, 1 i ; Aug. 4, 

 1936, Prison & Burks, A$ ; Aug. 21, 1936, 

 Ross & Burks, \S, 2 larvae; Kankakee 

 River, March 24, 1937, H. H. Ross, 1 S ; 

 May 17, 1937, Ross & Burks, 3S . Mount 

 Carmel: July 3, 1906, 1 S . Spring Grove: 

 May 20, 1938, at light, Ross & Burks, 2 6 ■ 

 Wilmington: April 23, 1935, Ross & 

 Mohr, 2 larvae; May 12, 1935, Prison & 

 Ross, S, 75 ; Kankakee River, May 17, 

 1935, H. H. Ross, S S, 9 $ ; May 27, 

 1935, Ross & Mohr, 1 larva, 1 pupa; June 

 6, 1935, Ross & Mohr, 7^,7 larvae; July 

 1, 1935, DeLong & Ross, U ; Aug. 20, 

 1935, DeLong & Ross, 2 $ ; Kankakee River. 

 May 17, 1937, Ross Si Burks, 1 S ; June 13. 

 1938, B. D. Burks, 6 6 . 



Hydropsyche phalerata Hagen 



Hydropsyche phalerata Hagen (1861, p. 287); 

 9. 



Larva. — Pig. 347. Length 13 mm. Head, 

 thoracic sclerites and legs with ground color 

 yellow; superimposed on this is an irregular, 

 dark, somewhat T-shaped area on the head 

 bearing a scattering of small black setae, 

 and scattered brown spots on the pronotum 

 and mesonotum, each bearing numerous 

 short, black setae. Frons almost flat and 

 with the apical margin produced into a low 

 triangular point. 



Adults. — Length 9-10 mm. Head and 

 body brown, wings tawny with brown areas 

 small and forming only a light and indefinite 

 pattern. Eyes of male medium sized, slight- 

 ly larger than half the area between them. 

 Male genitalia, fig. 371, with tenth tergite 

 upturned and incised to form forceps-like 

 lobes; aedeagus stout throughout, the apex 

 large, the lateral processes close together, 

 and the mesal cavity almost completely open. 

 Pemale genitalia, fig. 386F, very similar to 

 those of aerata. 



Until the selection of a lectotype by Banks 

 (1936^, p. 126), the status of this species 

 had been confused. The species considered 

 as phalerata by Betten (1934, p. 189) is 

 sparna ; and the species considered as Hydro- 



psyche species 3 by Betten (1934, p. 192) 

 is true phalerata. The color pattern of the 

 adults is fairly distinctive but requires actual 

 comparison with specimens to be of practical 

 use. 



In Illinois this species is apparently con- 

 fined to the northern fourth of the state, 

 where it has been taken abundantly in the 

 Kankakee River and in small numbers along 

 the Rock River and other creeks. Larvae 

 and pupae have been taken in rapids of the 

 Kankakee River. The adults emerge from 

 May to October. As in the case of bifida, 

 the heaviest flights of phalerata are taken 

 during the early summer months. 



The range of the species, fig. 15, extends 

 from the southern portion of the eastern 

 states to areas north of Illinois, and includes 

 Georgia, Kentucky, Illinois, Indiana, Michi- 

 gan, North Carolina, Ohio, Tennessee, Vir- 

 ginia and Wisconsin. 



Illinois Records. — Many males, females 

 and pupae, taken May 1 to September 7, 

 and many larvae, taken April 23 to October 

 28, are from Como (Rock River), Dixon 

 (Rock River), Prankfort (Clear Creek, 

 Hickory Creek), Kankakee, Lyndon (Rock 

 River), Momence (Kankakee River), New 

 Milford (Kishwaukee River), Oregon, 

 Rockford, Rock Island, Rockton, Sterling, 

 Wilmington (Kankakee River). 



Hydropsyche dicantha Ross 



Hydropsyche dicantha Ross ('1938rt, p. 146); 



This species, readily distinguished by the 

 unique male genitalia, fig. 373, has been 

 taken in extreme southwestern Michigan 

 and may eventually be found in Illinois, al- 

 though we have not as yet taken it here. 

 Few records are available for the species, 

 but they indicate a wide, scattered range, 

 as follows: District of Columbia, Kentucky, 

 Michigan, New York and Ontario. 



Female. — Length 9 mm. Color and gen- 

 eral stucture as described for male. Ninth 

 tergite, fig. 386^, with areas forming clasper 

 groove small and only indistinctly concave, 

 scarcely any indentation visible beneath dor- 

 sal cap from dorsal view; lateral lobe appar- 

 ently absent, the margin of the segment in 

 this region with a few setae. 



Allot>'pe, female. — Costello Lake, Al- 

 gonquin Park, Ontario, from Station 4, 

 Ontario Fisheries Research Laboratory: 

 July 7, 1938, W. M. Sprules. 



