46 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



length to basal segment; apico- 

 mesal process of seventh sternite 

 very long, fig. 167 moestus, p. 47 



Fig. 167. — Dolophilus moestus, 

 male genitalia. 



168 



Fig. 168. — Dolophilus moestus 9, maxillary 

 palpus. 



Fig. 169. — Dolophilus shawnee 9, maxillary 

 palpus. 



3. Maxillary palpi with second segment 

 cylindrical, of the same diameter as 

 first segment, fig. 168. . . .moestus, p. 47 

 Maxillary palpi with second segment 

 swollen on the mesal side, so that at 

 this point it is considerably wider 

 than the first segment, fig. 169. . . , 

 shawnee, p. 46 



Dolophilus shawnee Ross 



Dolophilus shawnee Ross (1938^, p. 133); 

 cf , 9. 



Larva. — Length 11-12 mm. Body slen- 

 der. Head, pronotum, legs and anal hooks 

 golden yellow. Head with a few long, scat- 

 tered setae and with a pair of transverse 

 brown bars near the posterior angle of the 

 frons; mandibles relatively small with fine 

 teeth near apex, fig. 173. Pronotum with 

 a row of scattered setae along the anterior 

 margin and another similar row across the 

 segment at the point of the attachment of 

 the legs. Body whitish when preserved, each 

 segment with two pairs of slender setae. 

 Anal hooks without inner teeth. Legs of 

 similar shape and proportions, only the first 

 pair with coxal spur. 



Adults.— Fig. 170. Length 7-9 mm. 

 Color of head, body and legs varying shades 



of brown; antennae annulate with tawny 

 and dark brown; wings uniformly gray. 

 Head and thorax bearing tufts of thick 

 tawny hair, and wings with fine, short, black 

 setae which give them a purplish shade. 

 Male genitalia, fig. 166, with claspers long, 

 the apical segment twice the length of the 

 basal segment. 



This species is very abundant locally in 

 clear, rapid, temporary streams in the 

 Ozark Hills of southern Illinois. The 

 adults are secretive and seldom captured 

 even in localities where the larvae and 

 pupae are abundant beneath almost every 

 stone. The species is single brooded, the 

 adults appearing in early spring. 



In addition to Illinois, known only from 

 Hopkinsville, Kentucky. 



Illinois Records. — Alto Pass, Union 

 Spring: May 26, 1940, Mohr & Burks, 3 

 larvae, 5 pupae. Eddyville, Lusk Creek: 

 May 24, 1940, Mohr & Burks, 5 larvae, 

 6 pupae; June 1, 1940, B. D. Burks, 1 



\^ 



Fig. 170. — Dolophilus shawnee. 



