ICHNEUMON-FLIES OF AMERICA: 1. METOPIINAE 263 



the female. It contains three known species, the two treated below 

 and Exochus citripes Thomson 1887, of Europe. 



54. Exochus decoratus Holmgren 



Figures 188,k; 190,r,u 



Front wing 4.4 to 7.0 mm. long; costula almost absent to complete; 

 second lateral area of propodeum about 0.92 as long as wide; second 

 tergite about 0.8 as long as wide, with about 400 hairs. 



Coloration variable, according to the subspecies. The two Nearc- 

 tic subspecies may be distinguished superficially from the closely re- 

 lated E. mandibularis by the fact that their mesopleurum is largely 

 or entirely pale, rather than black with the subtegular ridge and a 

 spot on the prepectus ivory. The European subspecies is colored 

 rather like E. mandibularis. 



The three subspecies are distinguished by the following key: 



1. Mesopleurum black, part of the prepectus and often an adjacent area on 



mesopleurum whitish to fulvous; range: Europe and Japan. 



54a. decoratus decoratus Holmgren 

 Mesopleurum mostly or entirely pale 2 



2. Hind femur whitish on its apical 0.2 to 0.3 and the apical part of its dorsal 



edge, the rest fulvous; range: Alaska to Arizona. 



54b. decoratus hebcs, new subspecies 



Hind femur entirely whitish or more or less fulvous on not more than its basal 



0.6 (fig. 196,h); range: New Brunswick, Quebec, and Ontario, south to 



Georgia 54c. decoratus seitulus Provancher 



54a. Exochus decoratus decoratus Holmgren 



Exochus decoratus Holmgren, 1873, Of vers. Svenska Vetensk. Akad. Forh., 

 vol. 30, p. 64; o". Type: d\ Scania, Sweden (?Stockholm). 



Male: Not known to the authors. 



Female: Front wing 4.4 to 5.3 mm. long; costula complete or in- 

 complete. 



Black. Face, side of frons (narrowed above), spot at top of eye 

 narrowly connected to mark on side of frons, clypeus, cheek, lower 

 0.4 of temple, mouth parts, under side of scape and pedicel, lower half 

 of propleurum, hind corner of pronotum, tegula, subtegular ridge, spot 

 on prepectus, sometimes a median spot on mesoscutum, scutellum 

 apically and laterally, postscutellum, front and middle legs, apical 

 0.2 ± of hind femur, and apical part of dorsal edge of hind femur, pale 

 yellow; flagellum brown beneath; mesopleurum often with a yellow 

 and fulvous area adjacent to yellow spot on prepectus; front and 

 middle femora and apex of their tibiae tinged with fulvous; hind tibia 

 and tarsus whitish, the basal and apical 1.5 of the tibia fuscous and 

 the apex of the last tarsal segment brownish. 



Specimens: Described from a female from Belgium and two females 

 from Japan. 



