ICHNEUMONID FINAL INSTAR LARVAE — SHORT 481 



Cresson, E. scitulus Provancher (fig. 48c), Chorinaeus sp. (GCV) 

 (fig. 49). 



Beirne (1941) figures Aletopius anxius Wesmael and Triclistus poda- 

 gricus (Gravenliorst) . 



Subfamily Ophioninae 



This subfamily has many characters resembling those of the Lissono- 

 tinae and Mesoleiinae. As stated in the introductory keys to sub- 

 families, it was found necessary to break up the Ophioninae into 

 tribes in order to differentiate these from the two related subfamilies. 



Tribe Canapoplegini 



Figures 50-56 



This tribe includes many important endoparasites of economic 

 pests. Most of the species attack lepidopterous larvae. Exceptions 

 include those of the genus Olesicampe parasitic on Tenthredinidae and 

 Diprionidae, of Biolysia and Bathyplectes parasitic on Curculionidae, 

 and of Pyracmon parasitic on wood-boring Coleoptera. 



The dorsal part of the epistoma is unsclerotized and the lateral parts 

 are lightly sclerotized; the pleurostoma is lightly sclerotized; the 

 hypostoma is long and well sclerotized; the hypostomal spur is short; 

 the stipital sclerite is present and its lateral end has a plate-like expan- 

 sion in many genera; the labial sclerite is longer than wide in most 

 genera and the ventral part is lightly sclerotized in many genera; the 

 prelabial sclerite is present and is Y-shaped in most genera; the labial 

 sclerite and the prelabial sclerite differ in shape in different genera; the 

 maxillary and labial palps each bear two sensilla, one large and one 

 small, in most genera; the silk press is well sclerotized; the labral 

 sclerite is absent; the mandible is of relatively moderate size and in 

 most genera the base is rather square and the blade slender ; in Pyrac- 

 mon and Prochas the blade is broad; the antenna is disc-shaped; the 

 closing apparatus of the spiracle is very lightly sclerotized and adjoins 

 the atrium; the skin has small projections and small setae, except in 

 Prochas, where the setae are equal in length to the blade of the man- 

 dible. 



The following key to genera is not particularly satisfactory. Some 

 genera have distinctive characters, but within certain genera, the 

 larval characters of the species examined differ widely. This might 

 indicate that the classification of the adults is greatly in need of re- 

 vision. One solution for the present stud}^ would have been to group 

 the species examined on larval characters only, ignoring the relation- 

 ships indicated by the U.S. Department of Agriculture's synoptic 

 catalog. This has been done to a very limited extent. For example 



