N.B.: the syllable -pagopus was formed from ancient Greek, means "frost foot" or "ice foot" and is masculine in gender (Tobias Joho, Institute of Classical Philology, University of Bern, Switzerland); considered a senior synonym of Melognathus Chamberlin, 1917 by Raven, 1985a: 156 and of Haplopelma Simon, 1892a: 151 [urn:lsid:nmbe.ch:spidergen:00229] (type Selenocosmia doriae Thorell, 1890) by Smith & Jacobi, 2015: 28; Melognathus revalidated by Gabriel & Sherwood, 2019c: 145; Haplopelma considered a senior synonym of Melopoeus Pocock, 1895a: 180 [urn:lsid:nmbe.ch:spidergen:05120] (type Selenocosmia albostriata Simon, 1886) by Raven, 1985a: 116 (but see also Schmidt, 2010b, who considered the type species a member of Ornithoctonus Pocock, 1892 and therefore considered Melopoeus the earliest available name for the remaining species, and Schmidt, 2015b, who removed Melopoeus from the synonymy with Haplopelma; Haplopelma, Cyriopagopus, Melopoeus and other "ornithoctonine" genera are in urgent need of revision (e.g. Hauke, 2017: 48); genus transfers and synonymies without thorough analysis and without including the type species will not be taken over.