ANNALS 



OF 



The Entomological Society of America 



Volume VI J U N E , I 9 1 3 Number 2 



A REVISION OF THE NORTH AMERICAN SPECIES OF 

 MEGASTIGMUS DALMAN, 



C. R. Crosby. 



The genus Megastigmus was founded by Dalman in 1820 

 (Svensk. Vet.-Akad. Handl. XLI, p. 178) as a subgenus of 

 Torymus to contain the three species: hipunctatus Swederus, 

 collaris and chloronotus. Collaris was described by Boheman 

 after Dalman's death in 1833 (Svensk. Vet.-Akad. Handl., p. 

 332). Chloronotus was never described but Boheman placed 

 it under Torymus (Megastigmus) dorsalis Fabricius (1. c. p. 334). 

 The type of the genus therefore cannot be M. dorsalis as stated 

 by Ashmead (Chalcis-flies, p. 380, 1904) but must be M. hi- 

 punctatus Swederus since that is the only one of the three 

 species cited by Dalman which was described at that time, 



Megastigmus is distinguished from other Torymidae occur- 

 ring in North America by the enlarged and pigmented stigmal 

 club and by the presence of a well developed basal vein. The 

 posterior tibice have two well developed apical spurs as in other 

 Torymidae; Ashmead's table to the subfamilies (Chalcis-flies, 

 p. 236, 1904) is in error on this point, and this mistake has 

 been copied by Schmiedeknecht in Genera Insectorum, fasc. 

 57, p. 118, 1909. The mandibles have three teeth. The 

 scutellum has a fine cross furrow as in Symtomaspis. The 

 ovipositor, except in two species, is longer than the abdomen, 

 slender and gently curved upward. The coloration in the 

 American forms is never metallic; usually yellowish brown or 

 opaque blackish. 



As far as known the larvae of all our species live in the seeds 

 of plants. 



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