ICHNEUMON-FLIES — GELINAE : MESOSTENINI 35 



13. Postpetiole slender, the part behind the spiracles 1.5 to 2.0 as long as wide; 



petiole terete, without a ventrolateral longitudinal carina; nervulus at 

 or distad of basal vein; subapical part of female flagellum widened; apical 

 part of axillus vein (the short vein in anal part of hind wing) at least as far 

 from anal margin of wing as from submediella; wings of all Nearctic 



species black 14. Joppidium (p. 306) 



Postpetiole usually stouter, the part behind spiracles usually 1.2 to 1.5 as 

 long as wide in males, 0.7 to 1.2 as long as wide in females; petiole usually 

 prismatic, with a ventrolateral longitudinal carina; nervulus at or basad 

 of basal vein; subapical part of female flagellum not widened except in 

 Reptatrix and in some species of Compsocryptus; apical part of axillus 

 vein closer to anal margin of wing than to submediella except in Compso- 

 cryptus and in some Neotropic species of Trachysphyrus; wings variously 

 colored, often subhyaline or banded, sometimes black 14 



14. Notaulus long, extending beyond center of mesoscutum (except in Trachy- 



sphyrus crassifemur, which species differs from those in second half of 

 couplet in having a pitlike depression on frons dorsolaterad of antennal 

 socket) ; wings usually hyaline or subhyaline but sometimes darker, banded 



only in Trachysphyrus fasciatus (fig. 339) 15 



Notaulus short, not reaching center of mesoscutum; wings usually dark 

 brown or banded with brown or black 16 



15. Punctures on tergite 2 small, usually weak, and in female usually sparse; 



propodeal spiracle short elliptic to elongate; thorax and abdomen not 

 variegated with white, red, and black in any Nearctic species. 



9. Trachysphyrus (p. 177) 



Punctures on tergite 2 coarse, strong, and rather dense; propodeal spiracle 



short elliptic; thorax and abdomen variegated with white, red, and black. 



10. Chrotnocryptus (p. 256) 



16. Apical part of axillus vein (the short vein in anal part of hind wing) equidis- 



tant between anal margin of wing and submediella, or closer to sub- 

 mediella (fig. 314,b); front side of areolet usually about as long as mesal 

 side; ovipositor rather long, upcurved . . 13. Compsocryptus (p. 278) 

 Apical part of axillus vein closer to anal margin of wing than to submediella; 

 front side of areolet shorter than mesal side; ovipositor rather short, 

 straight 17 



17. Clypeus about 2.0 as wide as long; hairs on thorax and on tergite 2 moderately 



sparse to dense in male, dense to very dense in female; subapical part of 



female flagellum not widened, terete 11. Lanugo (p. 259) 



Clypeus about 2.8 as wide as long; hairs on thorax and on tergite 2 rather 

 sparse in both sexes; subapical part of female flagellum a little widened, 

 flattened below 12. Reptatrix (p. 276) 



18. Frons with a median horn or pair of horns (best seen from above) ... 19 

 Frons unarmed, but sometimes with a median longitudinal carina or ridge . 23 



19. Apex of first abdominal sternite distad of spiracle; petiole rounded ventro- 



laterally, without a longitudinal ventrolateral carina 20 



Apex of first abdominal sternite opposite or basad of spiracle; petiole angled 

 ventrolaterally and with a more or less distinct ventrolateral longitudinal 

 carina, at least with a ventrolateral carina or flange on apical part of 

 petiole 21 



20. Second discoidal cell pointed or very narrow at base (fig. 319,b); areolet not 



wider than high (fig. 319,b) 23. Polycyrtidea (p. 405) 



Second discoidal cell broadly obliquely truncate at base (fig. 322,b); areolet 

 wider than high (fig. 322,b) 29. Polycyrtus (p. 459) 



