ICHNEUMON-FLIES — GELINAE : MESOSTENINI 355 



9. Trychosis latidens, new species 



Figure 389 



Front wing 5.2 to 7.2 mm. long; clypeus unusually wide, very 

 strongly convex, its apical margin moderately arcuate; mandible 

 large, unusually wide; temple moderately convex; cheek rather long, 

 usually partly mat, often with some weak horizontal wrinkHng, its 

 punctures of moderate size, separated by about 0.6 their diameter; 

 occipital carina strong and sharp, rather high but not lamellalike; 

 second segment of fiagellum about 2.4 as long as wide in male, about 

 3.75 as long as wide in female; thorax moderately long; notaulus 

 about 0.25 as long as mesoscutum; punctures on mesoplem"um small, 

 separated by about 0.4 their diameter; propodeum of moderate 

 length, in the female its apical carina rather weak, sublaterally form- 

 ing rudimentary crests, medially weak or obsolete, if present medially 

 curved forward and making a broad ''U" on the midline; hind femur 

 about 5.3 as long as deep in male, about 4.8 as long as deep in female; 

 sides of areolet wealdy convergent or subparallel; nervulus bej'ond 

 basal vein by about 0.3 its length; nervellus broken near its lower 

 0.45; petiole moderately long, with weak dorsolateral and ventro- 

 lateral ridges, its lateral face with indistinct, weak, fine wrinkling 

 that is weaker in female than in male; second tergite weakly mat, 

 its hair sockets separated by about 0.7 the length of the hairs but 

 often sparser near midlength of the tergite; ovipositor normal for 

 the genus. 



Male: Black. Palpi fuscous, segments 3 and 4 and apex of seg- 

 ment 2 of maxillary palpus yellowish ; tegula black ; front and middle 

 legs beyond trochanters ferruginous, the fifth segments of their tarsi 

 dark brown; hind femur ferruginous; hind tibia ferruginous to dark 

 ferruginous brown; hind basitarsus brown, a little paler at base and 

 apex, the apical 0.2 ± sometimes whitish; segments 2-4 of hind tarsus 

 whitish; segment 5 of hind tarsus dark brown; wings tinged with 

 brown; apical 0.35 ± of tergite 1, all of tergites 2-4, and often basal 

 part of tergite 5, ferruginous. 



Female : Black. Palpi fuscous, the apical thi-ee segments of maxil- 

 lary palpus brown; color otherwise as in male except that whitish 

 marking of hind tarsus is often partly obscured or entirel}'^ replaced 

 by brown. There is sometimes a whitish tinge on upper side of one 

 to three segments of fiagellum, near its midlength. A specimen from 

 Peaceful Valley, Colo., has the tergites 5 and 6 entirely ferruginous. 



This species is near T. semiruhra but differs in the larger size, 

 larger mandible, wider clypeus, longer notaulus, and more slender 

 proportions. 



