BRACHYGLUTINI 167 



Raffray (1904) divided the genus into four groups, and his key to these 

 groups has been followed, save that its expansion by the addition of a new group 

 for a remarkable new species, necessitated some alteration: 



Key to the Groups, based on males 



Eleventh antennal segment simple, ovate to elongate-ovate in form, 

 or at most slightly sinuate on interal face near apex, often as long as 

 the preceding three or four segments united 2 



Eleventh, tenth, and ninth antennal segments abnormal in shape or 

 structure, this abnormality marked 4 



2. Eleventh antennal segment regularly ovoidal 3 



Eleventh antennal segment irregularly ovoidal, and very obliquely 



truncate at base Group III 



3. First visible tergite with two thin, short basal carinae separated by 



one-fourth the segmental width Group I 



First visible tergite with no basal carinae visible Group II 



4. Ninth antennal segment not as large as tenth Group IV 



Ninth antennal segment much larger than tenth . . Group V, new group 



Alternative group key based on males 



Eleventh antennal segment simple, ovate to elongate-ovate in form, 

 and never abnormal in either sex save a slight sinuation on internal 

 face near apex (concavus) or a very slightly oblique base (simplex) 2 



Ninth, Tenth, and Eleventh antennal segments distinctly abnormal 

 in structure or outline 3 



2. First visible tergite with two thin, short basal carinae separated by 



one-fourth the segmental width Group I 



First visible tergite with no basal carinae Group II 



3. Eleventh antennal segment very obliquely and arcuately truncate at 



base, this obliquity paralleling the convex, arcuate apical margin of 

 the tenth segment, and the eleventh segment, therefore, having an 

 acutely produced basal external angle, with the external face of the 

 segment being longer than the internal face; known only from Mex- 

 ico; female with regularly ovate distal antennal segment 



Group III 



Abnormality of the antennal club very pronounced, but not identical 

 with the above 4 



4. Ninth antennal segment not as large as tenth segment. . . .Group IV 

 Ninth antennal segment very much larger than tenth antennal seg- 

 ment; known from the Panama Canal Zone. . .Group V, new group 



Group I 



Known only from Brazil marginalis 



Distributed north of the equator 2 



