Capitonius rubriceps Provancher, 1886:135 - 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 1. Symphyta and Apocrita (Parasitica). Smithsonian Institution Press, Washington D.C. 1-1198.:184 ( listed as synonym of Cenocoelius ashmeadii Dalla Torre, 1898).
Promachus rubriceps Ashmead, 1888:653, ♂. 2 ♂♂, Washington, D. C., February 14, 1884 (U. S. National Museum, No. 2566). - 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 1. Symphyta and Apocrita (Parasitica). Smithsonian Institution Press, Washington D.C. 1-1198.:184 ( listed as synonym of Cenocoelius ashmeadii Dalla Torre, 1898).
Cenocoelius Ashmeadii Dalla Torre, 1898:72, no descr. Replacement name for Promachus rubriceps Ashmead, 1888 by Dalla Torre, 1898Dalla Torre, C.G. 1898. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus. - IV: Braconidae. Sumptibus Guilelmi Engelmann, VIII + 323.:72. - Dalla Torre, 1898Dalla Torre, C.G. 1898. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus. - IV: Braconidae. Sumptibus Guilelmi Engelmann, VIII + 323. (distribution); 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 1. Symphyta and Apocrita (Parasitica). Smithsonian Institution Press, Washington D.C. 1-1198. (distribution).
Capitonius provancheri Rohwer, 1914:321 - 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 1. Symphyta and Apocrita (Parasitica). Smithsonian Institution Press, Washington D.C. 1-1198.:184 ( listed as synonym of Cenocoelius ashmeadii Dalla Torre, 1898).