Watson, Fletcher & Nye (1980) stated:-
Included in a work rejected for nomenclatural purposes by the International Commission on Zoological Nomenclature, 1966, Bull. zool. Nom. 23 (Opinion 789): 213. Placed on Official Index of Rejected and Invalid Generic Names in Zoology: Name No.1884. Two included species * Sphecomorpha polistes Hübner, 1808, ibidem: 4, later published and made available as Pseudosphex polistes Hübner, 1818, Zuträge Samml. exot. Schmett.1: 12 and * Sphecomorpha zethus Hübner, 1808, ibidem: 4, later published and made available as Pseudosphex zethus Hübner, 1818, ibidem 1: 13 (the type-species of Pseudosphex Hübner, 1818).
Sphecomorpha Hübner, 1806 was treated as a nomen-nudum by Hodges et al, 1983, Check list of the Lepidoptera of America north of Mexico including Greenland, p. 119.
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