METOPIINI 213 



fiavous, the specimen having apparently just pupated, (2) six sternites only, 



(3) fifth sternite short and subequal to fourth; sixth s^ernite long, as long as 

 second to fifth inclusive united and evenly convex, transversely acute-ovate, 



(4) metasternum simple and evenly tumid, (5) anterior trochanters simple, 

 not armed. 



Described from two specimens collected from Barro Colorado Island, 

 Gatun Lake, Panama Canal Zone. Holotype male collected by the author in 

 the morning of July 25, 1936, from stage four log mold at Drayton 12. Allotype 

 female collected by Alfred Emerson on May 4, 1935, from a cell in the nest of 

 the termite Termes panamaensis (Snyder). 



This is the only metopiine recorded with Isoptera. Its peculiar appearance 

 is largely that shared by the tribe as a whole but it may well prove to be a 

 synoekete of the termite noted above and the reduced eyes and complicated 

 cephalic sulci lend some credence to this view. The well-developed wings and 

 sharp, typically pselaphoid mandibles mitigate against a symphilic role in 

 the termite society. 



Taxonomically it is only related to Metopiosoma of Brazil and Argentina. 



Superficially it has the aspect of the goniacerine Bibrax of Barro Colorado 

 Island, but is readily separable as Bibrax bradleyi Fletcher has six sternites 

 in both sexes, strong and broad abdominal margins, eye composed of only a 

 single facet, no median pronotal sulcus and the first sternite long and clearly 

 visible from side to side, being longer than the posterior coxae. This similarity 

 in habitus between Goniacerini and Metopiini has been alluded to by students 

 previously (Fletcher, 1927) but the two tribes are basically very unrelated 

 as will be seen later. 



