212 G. E. J. NIXON 



white, much longer than the outer one and distinctly reaching beyond the middle of the hind 

 basitarsus ; hind tarsus having a somewhat bristly appearance. 



Tergite i twice as long as its middle width, hardly narrowed behind, humped longitudinally 

 where it turns over and its posterior, horizontal surface as long as wide, dull, densely, coarsely 

 rugose. Ovipositor sheath about three quarters as long as the hind tibia. 



Length: ca. 3-2 mm. without ovipositor. 



Brazil : Nova Teutonia, viii.1935, 1 $, the TYPE, (Plaumann). 

 Type in the British Museum (Nat. Hist.). 



This insect is hardly more than an isolated species within the zonaria-gvoxip, 

 differing from it only in the stronger development of the propodeal areolation and the 

 shape and sculpture of tergite 1. Unlike the species of the zonaria-group, the 

 occipital region in virbius is in no way differentiated from the vertex, the two regions 

 flowing smoothly into each other. 



The ZONARIA -Group 



This group contains the typical species of Hypomicrogaster and seems to be 

 confined to the American continent. 



Flagellum with a characteristic bristly appearance. Ocelli in a low triangle, the posterior, 

 transverse tangent to the anterior ocellus cutting the posterior pair. Occipital region gently 

 scooped out, the resultant polished area more or less delimited by being pushed forwards in front 

 right up to, and virtually touching, the posterior ocelli ; and delimited at sides by the distinctly 

 punctate temples. Pronotum with a dorsal furrow. Mesoscutum polished, punctate ; never 

 with satin-like sheen. Propodeum short, its areolation almost always irregular and poorly 

 defined ; if the propodeum shows a distinct postero-lateral field, then this is always distinctly 

 transverse. Inner spur of the hind tibia reaching at least considerably beyond the middle of the 

 hind basitarsus ; inner spur of the middle tibia very strong and distinctly longer than the middle 

 basitarsus. Areolet of the fore wing always very small, the 2nd transverse cubitus received onto 

 the 1st at a considerable distance from the junction of the 1st abscissa of the radius and the 1st 

 transverse cubitus. Ovipositor projecting freely, its sheaths at least half as long as the hind tibia. 

 Tergite 1 never narrowed behind. 



Muesebeck (1958 : 412) recognised the homogeneity of this group and suggested 

 that if more information were available it might be advisable to give it generic rank. 

 He gave a key to the five neotropical species known to him, all apparently closely 

 related and difficult to separate. Of these five, only imitator Ashmead is known to 

 me. It is possible that some of the species I now introduce as new will later fall as 

 synonyms of those dealt with by Muesebeck. 



The scooped-out occipital region is characteristic of all the species I include in the 

 key below (but head lost in type of imitator Ashmead). It does not occur in any of 

 the other species-groups I have placed in Hypomicrogaster . 



All the species keyed below have the face conspicuously but somewhat shallowly 

 rugose-punctate and the mesoscutum highly polished with moderately sharp, well 

 separated punctures. Further, the legs are predominantly bright yellow with the 

 hind femur yellow except for faint apical infuscation. 



