1606 Hymenoptera in America North of Mexico 



gracilis (Curtis). Pa. and N. J. to Tex. along coast, Ohio, Ind., Mich.; west. Europe. Ecology: 

 Nests in borings in twigs. Adventive from Europe. Parasite: Perithous divinator 

 (Rossi); Omalus auratus (L.). 



Diodontiis gracilis Curtis, 1834. Brit. Ent., v. 11, pi. 496. 6. 



Passaloecus turionum Dahlbom, 1844. Hym. Eur. 1: 246. 9,6. 



Passaloecus brevicomis Morawitz, 1864. Acad. Sci. St. Petersburg, Bui. 7: 462. 9,6. 



Taxonomy: Krombein, 1961. Ent. News 72: 258-259 (adventive in U. S. and separation from 

 N. Amer. spp.). 



Biology: Krombein, 1961. Ent. News 72: 258 (nest, parasite). 



marginatus (Say). Pa. 



Pemphredon marginatus Say, 1837. Boston Jour. Nat. Hist. 1: 379. 



melanocrus Rohwer. Tex., Colo., Ariz. Ecology: Nests in abandoned burrows of Dendroctonus 

 barberi Hopkins. 

 Passaloeais melanocrus Rohwer, 1911. U. S. Natl. Mus., Proc. 40: 561. cJ. 

 melanognathus Rohwer. Oreg., Calif. 



Passaloecus melanocpiathus Rohwer, 1910. Ent. Soc. Wash., Proc. 12: 104. 9. 

 monilicornis ithacae Krombein, n. status (D. Vincent). Mass., Conn., N. Y., Va., Ont., Mich., 

 Minn., Alta., Alaska. Ecology: Nests in borings in twigs and wood. Parasite: Omalus 

 aeneus (P.), 0. sp.; Poemenia albipes (Cr.), P. sp. Prey: Cinara hottesi (Gill, and Palm.), 

 C. abieticola (Choi.), C.fomacula Hottes, C. palmerae (Gill.), C. braggii (Gill), C. sp., 

 Neosymdobius americanus (Baker), Pterocomma smitkiae Mon. ?, Ainphorophora sp., 

 Anuraphis rosea Baker, Rhopalosiphum fitchii (Sand.), Euceraphis betnlae (Koch). 

 Typical monilicornis Dahlbom occurs in the Palaearctic Region. 

 Passaloecus ithacae Krombein, 1938. Brooklyn Ent. Soc, Bui. 33: 126. 9,6. 



Taxonomy: Evans, 1964. Amer. Ent. Soc, Trans. 90: 249-250, fig. 22 (larva). 



Biology: Fye, 1965. Canad. Ent. 97: 737-740, fig. 9 (nest, prey, parasites, life cycle). 

 —Krombein, 1967. Trap-nesting wasps and bees, pp. 234-236 (nest, prey, life cycle). 

 relativus Fox. Wyo., Colo., Utah, Nev., Ariz. Parasite: Poemenia americana nebulosa Hab. and 

 Tow. Predator: Philanthus pulcher D. T., P. pacificus Cr. 

 Passaloecus relativus Fox, 1892. Amer. Ent. Soc, Trans. 19: 319. 6. 



Taxonomy: Rohwer, 1909. Amer. Ent. Soc, Trans. 35: 100. 9. 

 singularis singularis Dahlbom. Mass., N. Y., Pa., Ohio, Mich., Utah, Colo.; Europe. Ecology: 

 Nests in abandoned burrows of Pissodes strobi (Peck). Possibly adventive in N. Amer. 

 Another subsp. occurs in Mongolia. 

 Passaloecus singularis Dahlbom, 1844. Hym. Europaea, v. 1, p. 243. 6. 

 Passaloecus tenuis Morawitz, 1864. Acad. Imp. des Sci. St. Petersburg, Bui. 7: 462. 9,6. 

 Passaloecus gertrudis Krombein, 1938. Brooklyn Ent. Soc, Bui. 33: 124. 9,6. 



Genus POLEMISTUS Saussure 



Polemistus Saussure, 1892. In Grandidier, Hist. Nat. Madagascar, v. 20, p. 565. 



Type-species: Polemistus macilentus Saussure. Desig. by Pate, 1937. 

 Polymistus Ashmead, 1899. Canad. Ent. 31: 222. Emend, or lapsus. 

 pusillus Saussure. Utah, Ariz.; Mexico. Ecology: Nests in abandoned Trypargilum mud nests 

 and makes cell partitions and nest closure from a transparent glass-like substance (resin 

 ?), and stores 6-8 aphids per cell. Parasite: Monodontomems sp.; Omalus sp., Chrysis 

 sp. Prey: Aphis gossypii Glov., A. sp., Macrosiphum sp. 

 Polemistus pusillus Saussure, 1892. In Grandidier, Hist. Nat. Madagascar, v. 20, p. 565. 9. 



Biology: Rau, 1943. Ent. Soc. Amer., Ann. 36: 647 (nest, prey, parasites). 



Tribe STIGMINI 

 Genus STIGMUS Panzer 



Taxonomy: Krombein, 1973. Biol. Soc. Wash., Proc. 86: 211-230, 16 figs, (synonymy, 

 distribution and key to N. Amer. spp.). 



