ICHNEUMON-FLIES OF AMERICA: 1. METOPIINAE 



127 



Figure 80. — Localities for 

 Triclistus Melanocephalus. 



Walley (Ottawa). 9, Westerly, R. L, Sept. 6, 1936, M. Chapman 

 (Townes). 9, Rapid Canyon, S. Dak., Aug. 4, 1924 (Washington). 

 9, Chain Bridge, Va., Sept. 18, 1921, J. R. Malloch (Washington). 

 9, near Plummers Island in Maryland, Va., July 9, 1923, H. S. Barber 

 (Washington). 9, Skyline Drive, Va., Aug. 6, 1945, H. and M. 

 Townes (Townes). 9, Polk Co., Wis., July (Washington). 9, 

 Sawyer Co., Wis., Aug. 1 to 8, 1937, D. Murray (St. Paul). 



This species occurs in the Alleghenian and Carolinian faunas, in 

 the mountains of Arizona, and in Northern Mexico. 



8. Genus Colpotrochia 



Figure 171, a 



Front wing 5.5 to 14 mm. long. Differs from Triclistus as stated in 

 couplet 10 of the key to genera (p. 7). Typical species of Colpotrochia 

 are easy to distinguish, as they have the temple very narrow and 

 sloping, the propodeum almost smooth and weakly convex, the first 

 tergite long and slender, and the abdomen banded with yellow. A 

 few of the exotic species of the subgenus Scallama, however, are rather 

 intermediate to Triclistus and need a careful application of the key 

 characters for distinguishing them from Triclistus. 



Colpotrochia is almost worldwide in distribution. Most of the 

 species are tropical. The usual habitat is rank, shaded shrubbery. 

 There are four species in eastern Nearctic America. 



The subgenera of Colpotrochia are separated by the following key: 



1. Nervellus strongly antef ureal (with its front end nearer the wing base than its 



hind end) ; areolet present. (Not Nearctic.) 1. Scallama 



Nervellus vertical or postfurcal (with its front end farther from wing base 



than its hind end) ; areolet present or absent. 2. Colpotrochia 



