Zethus sichelianus Saussure, 1875:254 - Zavattari, 1912Zavattari, E. 1912. Materialien für eine Monographie der Neotropischen Eumeniden. Archiv für Naturgeschichte 78:1-272. (distribution); Bodkin, 1918Bodkin, G.E. 1918. Notes on some British Guiana Hymenoptera (exclusive of the Formicidae). The Transactions of the Entomological Society of London 1917:297-321, pls. XXI-XXIII. (distribution).
Zethus cylindricus Fox, 1899:414, ♂♀. 3 ♀♀, 4 ♂♂, Chapada; Corumbá; Stange, 1997Stange, L.A. 1997. The Zethus of Venezuela (Hymenoptera: Eumenidae). Insecta Mundi 11 (3-4):311-324.:318, Lectotype ♂ (ICCM). Synonymized with Zethus sichelianus Saussure, 1875 by Zavattari, 1912Zavattari, E. 1912. Materialien für eine Monographie der Neotropischen Eumeniden. Archiv für Naturgeschichte 78:1-272.:65. - Stange, 1997Stange, L.A. 1997. The Zethus of Venezuela (Hymenoptera: Eumenidae). Insecta Mundi 11 (3-4):311-324. (distribution); Rasmussen & Asenjo, 2009Rasmussen, C. & A. Asenjo 2009. A checklist to the wasps of Peru (Hymenoptera, Aculeata). ZooKeys 15:1-78. (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).