120 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



447 



448 



Fig. 447. — Leucotrichia pictipes, front coxae. 

 Fig. 448. — Metrichia nigritta, front coxae. 



Metascutellum either triangular, fig. 

 440, or markedly narrower than 

 scutum, fig. 439 5 



5. Front tibiae with an apical spur 6 



Front tibiae without an apical spur. . 7 



6. Front coxae wide, fig. 447 



Leucotrichia, p. 120 



Front coxae narrow, fig. 448 



Metrichia, p. 121 



7. Hind tibiae with only 1 preapical spur 



Neotrichia, p. 154 



Hind tibiae with 2 preapical spurs. . . 8 



8. Middle tibiae without a preapical 



spur Mayatrichia, p. 160 



Middle tibiae with a preapical spur. . 9 



9. Mesoscutellum with a slightly arcuate, 



linelike fracture running from one 

 lateral angle to the other, fig. 441, 

 and dividing the area of the sclerite 

 almost equally. . . .Ochrotrichia, p. 125 

 Mesoscutellum without a transverse, 

 linelike groove 10 



10. Mesoscutellum narrow and diamond- 



shaped, with a wide area posterior 

 to postero-dorsal edge; metascutel- 

 lum with sides parallel to median 

 line and anterior margins forming 



a corner with sides, fig. 442 



Agraylea, p. 1 22 



Mesoscutellum wider, anterior margin 

 evenly curved, with postero-dorsal 

 edge close to or touching posterior 

 margin; metascutellum triangular, 

 arcuate or nearly so, figs. 443, 444 11 



11. Postero-dorsal edge of mesoscutellum 



touching posterior margin on meson; 

 metascutellum with posterior mar- 

 gin extending to lateral margin of 



segment, fig. 443 Oxyethira, p. 133 



Postero-dorsal edge of mesoscutellum 

 separated from posterior margin by 

 a narrow strip; metascutellum with 

 posterior margin not extending to 

 lateral margin but joined to it by a 



short, strapHke piece, fig. 444 



Ithytrichia, p. 123 



Leucotrichia Mosely 



Leucotrichia Mosely (1934^, p. 157). Geno- 

 type by original designation: Leucotrichia mel- 

 leopicta Mosely. 



Only one of the four Nearctic species 

 has been taken in Illinois. The remainder 

 are western or southwestern in distribution. 

 A key to Nearctic males is on page 271. 



Leucotrichia pictipes (Banks) 



Orthotrichia pictipes Banks (1911, p. 359); 

 &, 9. 



Larva (mature type). — Fig. 449. Length 

 4.5 mm. Sclerites dark brown. Segments of 

 thorax somewhat flattened, legs short and 

 stout. Abdomen with first two segments 

 very small, third to sixth greatly expanded; 

 each segment of abdomen with a conspic- 

 uous, rectangular, dark sclerite on the dor- 

 sum, each sclerite bearing several setae, 

 segments separated by a conspicuous con- 

 striction. Anal hooks sessile and fairly long. 

 Case. — Fig. 450. Round and convex, sim- 

 ilar in appearance to a leech egg, attached 

 like a water-penny, made of translucent ma- 

 terial which appears gelatinous but is actu- 

 ally quite tough. 

 Underside of case 

 formed of a weak, 

 irregular sheet. 



Adults. — Length 

 4.0-4.5 mm. Body 

 and appendages dark 

 brown to black, the 

 antennae and tarsi 

 banded with white, 

 the wings with a 

 few scattered, small 

 light areas. 



Fig. 449. — Leucotri- Fig. 450. — Leucotri- 

 chia pictipes larva. chia pictipes case. 



