282 U. S. NATIONAL MUSEUM BULLETIN 216 



This is a common species in Europe, and if permanently established 

 may become an important parasite in America. Specimens will key 

 to /. behrensii, which they resemble superficially, but may be dis- 

 tinguished from behrensii by the facts that the first trochanters are 

 fuscous and yellowish rather than fulvous and yellowish, and the 

 under side of the flagellum is yellowish rather than fuscous. 



Key to the Nearctic species of Itoplectis 



1. Hind tibia uniformly f ulvof erruginous ; coxae and first trochanters black 



(fig. 325,k) 3. viduata (Gravenhorst) 



Hind tibia white in or near the middle, black or blackish at base and apex; 

 coxae and first trochanters usually fulvous but sometimes partly or entirely 

 black 2 



2. Flagellum clavate, the subapical segments fully as wide as long; middle tibia 



and tarsus white 7. fustiger, new species 



Flagellum linear, not or slightly thickened apically, the subapical segments 

 longer than wide; middle tibia and tarsus white banded with darker, or 

 rather uniformly fulvous 3 



3. Median longitudinal earinae of propodeum extending about 0.7 its length; 



third through fifth tergites with very strong swellings and depressions; 

 ovipositor sheath about 0.9 as long as first tergite; front claws of female 



without a median tooth 8. curticauda (Kriechbaumer) 



Median longitudinal earinae of propodeum extending about 0.3 to 0.5 its 

 length; third through fifth tergites with moderate swellings and depressions; 

 ovipositor sheath 1.1 to 3.8 as long as first tergite; front claws of female 

 usually with a median tooth 4 



4. Tergites with a distinct white band on hind margin; abdomen narrower (third 



tergite of male about 1.0 as wide as long, of female about 1.6 as wide as long) ; 

 fourth and fifth tergites of male polished and with well-separated punctures. 



2. conquisitor (Say) 



Tergites without a distinct pale band along hind margin, or if such bands are 



present they are tan rather than whitish; abdomen broader (third tergite 



of male about 1.8 as wide as long, of female about 2.1 as wide as long) ; fourth 



and fifth tergites of male mat and with crowded punctures 5 



5. Temple rather strongly convex; face unusually wide; ovipositor sheath about 



3.6 as long as first tergite; front tarsal claws of female without a tooth; ovi- 

 positor distinctly decurved 4. evetriae Viereck 



Temple rather weakly convex; face of moderate width; ovipositor sheath 

 about 2.4 as long as first tergite; front tarsal claws of female with a tooth 

 except in most specimens of /. vesca 6 



6. Tergites 2-7 ferruginous laterally; coxae blackish, pale at extreme apex; 



front tarsal claws of female with a small, acute median tooth. 



5. behrensii (Cresson) 



Tergites 2-7 entirely black except for paler apical margins; coxae fulvous to 



black; front tarsal claws of female each with a large tooth, a very small tooth, 



or without a tooth 7 



7. Middle and hind first trochanters entirely fulvous; notaulus absent; front 



tarsal claws of female with a broad postmedian tooth. 



1. quadricingulata (Provancher) 



Middle and hind first trochanters largely or entirely fuscous; notaulus present 



but weak; front tarsal claws of female with a minute median tooth or without 



a tooth 6. vesca, new species 



