70 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



262 A 



VESTITUS 



263 A 



UNCUS 



Figs. 262-263. — Nyctiophylax, male geni- 

 talia. A, lateral aspect; B, clasper, caudal 

 aspect. 



Apex of abdomen with platelike lateral 



lobes, fig. 264 (females) 



not keyed 



2. Posterior aspect of claspers with mesal 

 lobe produced into a long finger, 



fig. 263 uncus, p. 70 



Posterior aspect of claspers with mesal 

 lobe no higher than lateral lobe, 

 fig. 262 vestitus, p. 70 



Nyctiophylax vestitus (Hagen) 

 Polycentropus vestitus Hagen (1861, p. 293); 



9. 



Polycentropus affinis Banks (1897, p. 30); d^. 

 Nyctiophylax moestus Banks (1911, p. 359); 



Larva. — Unknown. 



Adults. — Length 5-7 mm. Color various 

 shades of brown, the wings with light spots 

 in an irregular pattern. Male genitalia, fig. 

 262: tenth tergite semimembranous, short, 

 narrowed at apex; cerci forming a some- 

 what ovate lobe with a sharp process on the 

 mesal face near venter; claspers appearing 

 narrow from lateral view, the extreme base 

 produced into a short shelf, the apical por- 

 tion with a broad, concave, posterior face 

 which is divided at apex into a pair of short 

 lobes, the inner one small. Female geni- 

 talia, fig. 264: lateral lobes of eighth ster- 

 nite short and wide; bursa copulatrix vari- 

 able, but always with a shieldlike structure. 



In Illinois this species occurs associated 

 with a wide variety of small to large streams 

 over most of the state. Adult emergence 

 begins in May and continues until at least 

 September. 



The species is apparently widespread 

 through the Northeast and continues south- 

 westward through the Ozarks to Oklahoma. 

 We have records from Arkansas, Illinois, 

 Indiana, Kentucky, Maryland, Michigan, 

 Minnesota, New York, North Carolina, 

 Ohio, Oklahoma, Ontario, Quebec, Tennes- 

 see and Wisconsin. 



Illinois Records. — Many males and fe- 

 males, taken May 19 to September 20, are 

 from Algonquin, Alto Pass (Union Spring), 

 Antioch, Apple River State Park, Barton- 

 ville (Kickapoo Creek), Charleston, Coun- 

 cil Hill (Galena River), Danville (Middle 



Fig. 264. — Nyctiophylax vestitus, female gen- 

 italia. A, ventral aspect; 5, dorsal aspect of 

 bursa copulatrix. 



Fork River), Downs (Kickapoo Creek), 

 Eddyville (Lusk Creek), Eichorn (Hicks 

 Branch), Elgin (Botanical Gardens), Fox 

 Lake, Galena (Sinsinawa River), Grass 

 Lake, Herod, Kankakee (Kankakee River), 

 McHenry, Momence (Kankakee River), 

 Mount Carroll, Muncie, Oakwood (Salt 

 Fork, Middle Fork, Vermilion River), Ore- 

 gon, Ottawa, Pontlac, Quincy (stream near 

 Cave Spring), Serena (Fox River, Indian 

 Creek), Springfield (Sangamon River), 

 Spring Grove (Nippersink Creek), Sugar 

 Grove, Venedy Station (Kaskaskia River), 

 Wadsworth (Des Plaines River), Wauke- 

 gan, White Pines Forest State Park, Wil- 

 mington. 



Nyctiophylax uncus new species 



Male. — Length 6.5 mm. Color various 

 shades of brown, the wings only indistinctly 

 spotted, the antennae and legs straw colored 

 except for the hind tibiae which have the 

 apical five-sixths dark brown, forming a 

 conspicuous pale annulus at base. Wings 

 with Rg absent. Male genitalia with gen- 



