350 U. S. NATIONAL MUSEUM BULLETIN 216 



17. Coccygomimus dimidiatus, new species 



Male type: Front wing 5.3 mm. long; face with rather dense, 

 medium-sized, subadjacent punctures; temple in profile 0.54 as long 

 as eye; mesopleurum and metapleurum with medium-sized, rather 

 sharp punctures that are separated by about 0.6 their diameter on 

 mesopleurum and somewhat closer on metapleurum, the metapleurum 

 with weak oblique wrinkles; epipleura of second, third, and fourth 

 tergites respectively 1.8, 1.65, and 1.45 as long as wide. 



Black. Clypeus dusky fulvous, its basal part blackish; palpi 

 fulvous; antenna fulvous brown; tegula light fulvous; legs fulvous, 

 the apical part of fifth segment of front and middle tarsi light brown, 

 hind tarsus brown, and apical 0.06 of hind tibia a little infuscate; 

 abdomen entirely fulvous; wings hyaline. 



Female: Unknown. 



Type: d", Hempstead, Tex., Mar. 3, 1942, A. L. Melander (Cam- 

 bridge). 



4. Tribe Theroniini 



Figures 299,b-300,b 



Front wing 5 to 19 mm. long; clypeus transverse, its basal portion 

 weakly convex or almost flat, its apical portion often a little de- 

 pressed, often divided into two lobes by a notch in its apical margin 

 but in the genera Pseudorhyssa and Atraetogaster with a median 

 apical tubercle; mesoscutum in Pseudorhyssa with close, transverse 

 wrinkles, in other genera without wrinkles; prepectal carina present; 

 mesopleural suture with an angulation near the middle; propodeal 

 carinae bounding the petiolar area and usually bounding the areola 

 more or less distinctly, in some species of Theronia all the carinae 

 present; last segment of tarsus sometimes enlarged; tarsal claws 

 simple, in the genus Theronia with an enlarged hair that is flattened 

 at the tip; areolet present; nervellus broken near, somewhat below, 

 or above the middle; subgenital plate of male usually longer than wide, 

 sometimes with an acute or rounded apical point; last tergite of fe- 

 male without an apical horn or boss; ovipositor short to long, of uni- 

 form width, more or less compressed. 



As defined here, this tribe includes the genera Theronia, Delo- 

 merista, Atraetogaster, and Pseudorhyssa. Whether or not they are 

 really related has not been proven, but they do have certain characters 

 in common. The adult characters are described above. The larvae 

 of Theronia, Delomerista, and Pseudorhyssa are similar in having a 

 large internal tooth on the mandible. Larvae of Atraetogaster are 

 unknown. We are indebted to Dr. G. H. Thompson, of Oxford, 

 for information about the larva of Pseudorhyssa. 



