Ceccolini, F. 2023. Pelopaeus aterrimus Marquet, 1875, a new synonym of Sceliphron spirifex (Linnaeus, 1758) (Hymenoptera: Sphecidae). Zootaxa. 5271, 3 (Apr. 2023), 599–599. DOI:https://doi.org/10.11646/zootaxa.5271.3.13.