226 U. S. NATIONAL MUSEUM BULLETIN 209 



interrupted row; last segment of tarsi without distinct preapical 

 spinelike bristles; female subgenital plate strongly compressed, at the 

 apex with a brief, ventral, longitudinal ridge; sting straight, strong. 

 There is a single, widely distributed genus. 



Genus^Minagenia, Banks 



Minagenia Banks, 1934, Proc. Amer. Acad. Arts. Sci., vol. 69, pp. 40, 64. Type: 

 Pseudagenia (Minagenia) brevicornis Banks; original designation. 



Nannochilus Banks, 1944, Bull. Mus. Comp. Zool., vol. 94, p. 171. Type: Pseuda- 

 genia externa Banks; original designation. 



Minagenia probably has a wide distribution, but seems to be rare 

 outside of the Western Hemisphere. Besides the genotype from the 

 Philippines, I have seen a paratype of the Madagascan Micragenia 

 minima Banks 1941, which is referable to^Minagenia (new combi- 

 nation). The Nootropic species of which I have seen the types are 

 Pompilus levipes Cresson 1869, Nannochilus obscurus Banks 1946, 

 N. peruanus Banks 1946, A^. laevis Banks 1946, and Minagenia minor 

 Dreisbach 1953 (all but M. minor are new combinations in Minagenia). 



The Neartic species have a close structural similarity and a variable 

 coloration. They are best distinguished by the male genitaHa. These 

 structures, however, are variable within a species, so that a series is 

 needed for understanding the basic specific patterns. The females 

 belonging with the males have been identified with certainty in some 

 cases, in other cases with doubt or not at all. In the treatment 

 below females are included only in those cases where correlations 

 with the males are certain or probable. 



What little is known about the biology of Minagenia indicates 

 that the larva lives as an external parasite on the abdomen of an 

 active spider, somewhat like the polysphinctine ichneumonids. The 

 cocoon apparently is spun under bark or in similar places, probably 

 wherever the spider succumbs. 



Keys to the Nearctic Species of Minagenia 



MALES 



(The male of externa is unknown.) 



1. Subgenital plate with a sharp median longitudinal ridge, the plate sharply 



folded longitudinally; clypeus, abdomen, and femora black; genitalia as in 



plate 4, figure 48 9. montisdorsa Dreisbach 



Subgenital plate without a median longitudinal ridge, flat or having the sides 

 uncurved (pi. 4, figs. 45, 46, 47); clypeus, abdomen, or femora often pale ... 2 



2. Second to fifth sternites with numerous suberect long hairs; apical part of 



paramere very slender but without unusually long bristles (pi. 3, fig. 38). 



6. osoria (Banks) 



Second to fifth sternites with a few oblique long hairs or without unusually 



long hairs; apical part of paramere not unusually slender, or, if unusually 



slender, then with unusually long bristles 3 



