1197 



Superfamily TRIGONALOIDEA 



By Robert W. Carlson 



Family TRIGONALIDAE 



According to Malyshev (1968) this small family includes about 70 species which are scattered 

 throughout the world. The species are all parasitic. The hymenopterous or dipterous primary 

 hosts are usually parasites or predators of larval Lepidoptera. It is thought that at least some 

 species can be primary larval parasites of sawflies, and Cooper (1954) hypothesized that sawflies 

 were the hosts of ancestral Trigonalidae. That seems quite possible in view of the isolated and 

 undeterminable phyletic position of the family, but I know of no rearings of Nearctic trigonalids 

 as primary or secondary parasites of sawflies. 



Trigonalid eggs are deposited singly on the leaves of angiosperms, apparently always near the 

 edges of leaves. They are tiny and tough-shelled, enabling them to be ingested without destruc- 

 tion by leaf feeding caterpillars. It appears that if the tough shell is not cracked when an egg is 

 ingested hatching does not occur. Eclosion from the egg occurs in the intestine of the caterpillar, 

 and the first instar trigonalid bores through the intestinal wall and apparently remains in the 

 body cavity of the caterpillar without developing further pending parasitization of the caterpil- 

 lar by an ichneumonid or tachinid or predation upon it by a social or solitary vespid. When the 

 primary host is a social vespid, a first instar trigonalid would apparently be fed to a larval 

 vespid by a foraging worker. 



Revision: Townes, 1956. U. S. Natl. Mus., Proc. 106: 295-304. 



Ta.xonomy: Schulz, 1907. hi Wytsman, Gen. Ins., fasc. 61, 24 p. (Genera of world). — Bischoff, 

 1938. //( Hedicke, Hym. Cat., pt. 5, 18 p. (world catalog). 



Biology: Clausen, 1929; 1931. Ent. Soc. Wash., Proc. 31: 67-79; 33: 70-81. -Clausen, 1940. 

 Entomophagous Insects, p. 56-61. —Cooper, 1954. Ent. Soc. Wash., Proc. 56: 280-288. 

 —Malyshev, 1968. Genesis of Hym. and ... their Evolution, p. 88-95. 



Genus ORTHOGONALYS Schulz 



Orfhogoiioh/s Schulz, 1905. Hym. Stud., p. 76. 



Type-species: Orthogonal t/s boliriana Schulz. Monotypic. 

 Orthogonalos Schulz, 1907. In Wytsman, Gen. Ins., fasc. 61, p. 8. Emend. 

 TapinogoHalos Schulz, 1907. In Wytsman, Gen. Ins., fasc. 61, p. 14. 



Type-species: Trigonalys pukliellus Cresson. Desig. by Viereck, 1914. 

 pulchella (Cresson). Southern Maine s. to n. Va., w. to w. N. Y. and W. Va. Host: Avchijtas 

 aterriwus (R.-D.), NHea lobeliae (Coq.). 

 Trigonalijn pMlchelliis Cresson, 1867. Ent. Soc. Phila., Proc. 6: 351. 6. 



Biology: Townes, 1956. U. S. Natl. Mus., Proc. 106: 298 (oviposition behavior). 



