﻿PROCEEDINGS OF THE UNITED STATES NATIONAL MUSEUM 



issued n^ik d cil^l ^y ^ 



SMITHSONIAN INSTITUTION 



U. S. NATIONAL MUSEUM 



Vol. 100 Washington: 1950 No. 3259 



THE NEARCTIC SPECIES OF GASTERUPTIIDAE 

 (HYMENOPTERA) 



By Henry Townes 



The Hymenoptera treated herein have previously been included 

 in the family Evaniidae or in the separate families Gasteruptiidae ^ 

 and Aulacidae. It is now generally agreed that they have little in 

 common with the Evaniidae and that the main character by which 

 they were formerly associated, the high attachment of the abdomen 

 to the thorax, has been acquired independently in the two groups. 

 Subsequent to their taxonomic separation from the Evaniidae, these 

 insects were segregated as the families Aulacidae and Gasteruptiidae. 

 Close similarity in fundamental structm-e suggests that they are better 

 treated as two subfamilies of a single family. Comparing members 

 of the weU-known genus Gasterwption with the Aulacinae, one finds 

 striking differences in body form and in venation, but there are also 

 many points of structural agreement. When the primitive, less well 

 known Gasteruptiinae of the Australian Region (Hyptiogaster, etc.) 

 are compared with the Aulacinae, many of the differences of body 

 form and venation apparent when only Gasteruption is used disappear. 

 Those remaining are tabulated in the key to subfamilies below. Struc- 

 tural peculiarities that run through the whole family in its broader 

 limitation, but that are often overlooked, are the partial to complete 

 fusion of the first two abdominal tergites and the fact that the antenna 

 has 13 segments in the male and 14 in the female. At present the family 



• This name is usually spelled Gasteruptlonidae, but the stem of the type generic name (Oasteruption) is 

 Qasterapti-, which with the addition of -idae results in Gasteruptiidae. 



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