Zethus aztecus Saussure, 1857:270,Le Mexique (Tampico); Bequaert, 1928Bequaert, J.C. 1928. A study of certain types of diplopterous wasps in the collection of the British Museum. The Annals and Magazine of Natural History ser. 10: v. 2 (7):138-176.:156, the holotype, however, is not in the British Museum. - Dalla Torre, 1894Dalla Torre, C.G. 1894. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus, IX. Vespidae (Diploptera). Guilelmi Engelmann, 181. (distribution); Ashmead, 1896Ashmead, W.H. 1896. Notes on the Hymenoptera. Collected by the Bahama expedition fromt the State University of Iowa. Bull. Lab. Nat. Sci. :28-32. (distribution); Ashmead, 1900Ashmead, W.H. 1900. Report upon the aculeate Hymenoptera of the islands of St. Vincent and Grenada, with additions to the parasitic Hymenoptera and a list of the described Hymenoptera of the West Indies. Transactions of the Entomological Society of London pt. II:207-367. (distribution); Porter, 1975Porter, C.C. 1975. New records for Zethus from Texas (Hymenoptera: Eumenidae). The Florida Entomologist 58 (4):303-306. (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 2. Apocrita (Aculeata). Smithsonian Institution Press, Washington D.C. 1199-2209. (distribution); West-Eberhard et al., 1995West-Eberhard, M.J., J.M. Carpenter & P.E. Hanson 1995. The vespid wasps (Vespidae). In: Hanson, P.E. & I.D. Gauld (Ed.). The Hymenoptera of Costa Rica. 561-587. (distribution); Ruíz-Cancino & Coronado-Blanco, 2002Ruíz-Cancino, E. & J.M. Coronado-Blanco 2002. Artrópodos terrestres de los estados de Tamaulipas y Nuevo León, México. Serie Publicaciones Cientificas No. 4:1-376. (distribution); Ruíz-Cancino et al., 2005Ruíz-Cancino, E., J.M. Coronado-Blanco & J.V. Horta Vega 2005. Conocimiento actual de las avispas depredadoras (Hymenoptera) en Tamaulipas, México. In: Lozano, L. B., A.C. Sandoval, J.V.H. Vega & J.G. Jiménez (Ed.). Biodiversidad tamaulipeca: vol. 1. 164-170. (distribution); Ruíz-Cancino et al., 2010Ruíz-Cancino, E., D.R. Kasparyan, J.M. Coronado-Blanco, S.N. Myartseva, V.A. Trjapitzin, S.G. Hernández Aguilar & J. García Jiménez 2010. Himenópteros de la Reserva “El Cielo”, Tamaulipas, México. Dugesiana 17 (1):53-71. (distribution); Carpenter et al., 2012Carpenter, J.M., B.R. Garcete-Barrett & Y.J.A.F. López 2012. Las Vespidae (Hymenoptera: Vespoidea) de Guatemala. In: Cano, E.B. & J.C. Schuster (Ed.). Biodiversidad de Guatemala. Volumen 2. 269-279. (distribution).
Zethus campestris Zavattari, 1913:108, Bequaert, 1928Bequaert, J.C. 1928. A study of certain types of diplopterous wasps in the collection of the British Museum. The Annals and Magazine of Natural History ser. 10: v. 2 (7):138-176.:155, Holotype ♀ (British Museum). Synonymized with Zethus aztecus Saussure, 1857 by Bequaert, 1928Bequaert, J.C. 1928. A study of certain types of diplopterous wasps in the collection of the British Museum. The Annals and Magazine of Natural History ser. 10: v. 2 (7):138-176.:155. - 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.:1509 ( listed as synonym of Zethus aztecus Saussure, 1857).