ICHNEUMON-FLIES, PART 2 1 EPHLVLTINAE 7 



The larvae feed externally on the hosts and in correlation with this 

 habit have rather large mandibles with serrate edges. 



The tribe is difficult to divide into satisfactory genera. It is one 

 of those situations in which the careful taxonomist would prefer to 

 withhold judgment until much more information is available. The 

 position of indecision, however, should not be maintained too long 

 and we have written down our best judgment for the present. We 

 hope that it proves to be useful and to have resulted in progress in 

 the right direction. The keys were devised for maximum ease of 

 use and accuracy, but are not foolproof. Interpretation of some of 

 the characters needs experience, and the question of where the 

 nervellus is broken (couplet 7) will, in borderline or questionable 

 cases, require a trial run through both halves of the couplet. Some 

 exotic species will not conform to all key characters. The genera may 

 be grouped into assemblages which to a large degree seem to correspond 

 to their real relationships. These are discussed below. 



Pimpla group: Occipital carina complete, or rarely obsolete medi- 

 ally; tarsal claws of female with a lobelike tooth (except in Eremo- 

 chila) ; male subgenital plate not elongate. There are two subgroups : 

 A. The Pimpla subgroup tends to have a prominent dip on the 

 midline above the occipital carina, temples tend to be broad, clypeus 

 flatter, subgenital plate of female usually with a large, median mem- 

 branous area, upper valve of ovipositor usually not attenuate at apex, 

 and ridges of basal teeth of lower valve of ovipositor moderately 

 oblique to vertical. The genera are Exeristes, Eremochila, Scambus, 

 Flavopimpla, Calliephialtes, Holcopimpla, Delaulax, Xanthephialtes, 

 Xanthophenax, Pimpla, Apistephialtes, Anastelgis, Dolichomitus , Afre- 

 phialtes, Mesoephialtes , Pimplaetus, and two undescribed genera. 

 These genera are parasitic on larvae in plant tissues (buds, leaf rolls, 

 stems, wood, etc.) and oviposition is through plant tissue to reach the 

 host. B. The Tromatobia subgroup tends to lack the median dip in 

 the occipital carina or to have only a weak dip, the temples usually 

 narrower, clypeus more convex, subgenital plate of female usually 

 completely sclerotized, upper valve of ovipositor usually with an 

 attenuate point, and ridges of basal teeth of lower valve of ovipositor 

 very oblique. The genera are Acropimpla, Sericopimpla, Cnemo- 

 pimpla, Iseropus, Tromatobia, Zaglyptus, and Clistopyga. These 

 genera are parasitic on cocoons of various kinds, including spider egg 

 cocoons, and oviposition is through silk to reach the host. 



Alophosternum group: Occipital carina absent medially above; 

 mesoscutum covered with moderately dense hairs; tarsal claws of 

 female with a basal tooth on the front claws, with or without a basal 

 tooth on the middle and hind claws; male subgenital plate not 

 elongate; basal half of ovipositor weakly decurved. Alophosternum 



