1936] 
An American Species of Solenopsia 
15 
AN AMERICAN SPECIES OF SOLENOPSIA 
By Charles T. Brues 
Biological Laboratories, Harvard University 
The genus Solenopsia was first described by Wasmann in 
1899 to include a very peculiar subapterous species of Dia- 
priidae from Europe. This extremely minute insect, found 
in nests of the thief ant, Solenopsis fugax, in Holland, 
France, and Italy is exceedingly ant-like in form, even to 
the development of a scale-like node on the dorsal face of 
the abdominal petiole. Of this species Wasmann knew only 
the female, but the male of a second species, S. castanea, has 
been since described by Kieffer from the Pyrenees in South- 
ern France where it lives in nests of Solenopsis geminata. 1 
Like the female, the male is practically wingless, but the an- 
tennae are not so strongly clavate. 
Solenopsia differs from all other Diapriidae in the form of 
the abdominal petiole which is developed into an elevated 
node like that found only in certain ants, although it resem- 
bles that of a formicine or dolichoderine rather than that of 
a myrmicine ant, and the host with which it has been found 
in Europe is one of the Myrmicinae. 
Last summer I received from Professor C. H. Kennedy of 
Ohio State University several very beautifully executed pen- 
cil sketches of a minute strange hymenopterous insect that 
had been found in a nest of Prenolepis parvula in eastern 
Tennessee by Professor Clyde Dennis of Tusculum College. 
These sketches indicated that it was either a diapriid like 
Solenopsia or perhaps an aberrant embolemid. 
At Professor Kennedy’s suggestion I have since examined 
the specimen and it proves without question to be a species 
of Solenopsia, the first to be discovered in the New World. 
It is closely similar to the European forms but the resem- 
blance between the abdominal petiole and that of its host is 
1 Wasmann cites it as a guest of this ant, although Kieffer gives S. 
fugax as the host ant. 
