ICHNEUMON-FLIES OF AMERICA! 1. METOPIINAE 181 



2. Exochus mitratus Gravenhorst 



Figures 188,b; 189,a 



Front wing 4.5 to 6.3 mm. long; apex of interantennal process of 

 face not touching frons but separated from it by a distinct gap; second 

 segment of middle tarsus of male about 1.4 as long as wide, of female 

 about 1.35 as long as wide; body punctation a little weaker than in 

 Exochus turgidus. 



There are two American subspecies, as described below. Three 

 additional subspecies occur in Europe and a fourth in Japan. The 

 European subspecies are Exochus mitratus mitratus Gravenhorst 

 1829, E. mitratus australis Thomson 1895 (new status), and E. mitratus 

 affinis Holmgren 1856 (new status). Of these three, we have not seen 

 material of the subspecies australis, but place it from descriptions. 

 The subspecies affinis is very close to the Nearctic atrocoxalis, our 

 single specimen of affinis differing in having the tegula brown with its 

 front third ivory, rather than pale brown with its front 0.35 and hind 

 corner ivory. The Japanese subspecies seem to be undescribed. 

 We have a single specimen of it, from Tokyo. 



The American subspecies of E. mitratus are separated by the follow- 

 ing key: 



1. Upper margin of pronotum entirely white or with a large white triangle next 

 to the tegula; basal 0.2 of hind tibia yellowish, distinctly paler than the rest of 

 the tibia; range: east of long. 100° W. . .2a. mitratus atrocoxalis Cresson 

 Upper margin of pronotum black, or sometimes with a narrow white line on 

 its extreme posterodorsal corner; basal 0.2 of hind tibia ferruginous like the 

 rest of the tibia or sometimes a little paler; range: west of long. 100° W. 



2b. mitratus orias, new subspecies 



2a. Exochus mitratus atrocoxalis Cresson, new status 



Exochus atrocoxalis Cresson, 1868, Trans. Amer. Ent. Soc, vol. 2, p. 114, 9. 

 Lectotype: 9 , Dakota Territory (Philadelphia). 



Black. Interantennal process, upper lateral corner of face, usually 

 entire upper margin of face and small spot at top of eye, whitish; 

 upper margin of pronotum partly or entirely yellowish white; sub- 

 tegular ridge usually narrowly yellowish white; tegula pale yellow, 

 with a pale brown postmedian area, its apex always whitish; apex 

 and side margin of scutellum often whitish; postscutellum often 

 whitish; front femur apically yellowish; narrow apex of middle and 

 hind femora often more or less yellowish, especially in males; coxae 

 black; first trochanters black or blackish; legs fulvous except as 

 described otherwise; wings subhyaline. In a specimen from Wright, 

 Quebec, the coxae and trochanters are entirely fulvous, and in one 

 from Wexford Co., Mich., the hind coxa is largely fulvous. In the 

 rest of our specimens they are black. 



