Pompilus subopacus Cresson, 1867:114, ♂♀. 1 ♀, 1 ♂, Pennsylvania (Am. Ent. Soc.). - Dalla Torre, 1897Dalla Torre, C.G. 1897. Catalogus hymenopterorum hucusque descriptorum systematicus et synonymicus. Volumen VIII: Fossores (Sphegidae). Breitkopf & Härtel, Leipzig. 1-749.:241 (listed); Townes, 1957Townes, H. 1957. Nearctic wasps of the subfamilies Pepsinae and Ceropalinae. Bulletin of the United States National Museum 209:1-286.:72 (listed). - As Chilochares subopacus: - Banks, 1941Banks, N. 1941. A partition of our Cryptochilus, with some new Psammocharidae (Hymenoptera). The Canadian Entomologist 73:119-122.:120 (comb. nov.). - As Cryptocheilus subopacus: - As Cryptocheilus subopacus: - As Cryptocheilus terminatum subopacum: - Townes, 1957Townes, H. 1957. Nearctic wasps of the subfamilies Pepsinae and Ceropalinae. Bulletin of the United States National Museum 209:1-286.:72 (listed); Krombein et al., 1979Krombein, K.V., P.D. Hurd, D.R. Smith & B.D. Burks 1979. Catalog of Hymenoptera in America North of Mexico. Volume 2. Apocrita (Aculeata). Smithsonian Institution Press, Washington D.C. 1199-2209. (distribution). - As Priocnemis subopacus: - Cresson, 1887Cresson, E.T. 1887. Synopsis of the families and genera of the Hymenoptera of America, North of Mexico. Transactions of the American Entomological Society Supplementary Volume:1-350.:272 (listed). - As Salius subopacus: - Dalla Torre, 1897Dalla Torre, C.G. 1897. Catalogus hymenopterorum hucusque descriptorum systematicus et synonymicus. Volumen VIII: Fossores (Sphegidae). Breitkopf & Härtel, Leipzig. 1-749.:241 (listed).