Fletcher & Nye (1982) stated:-
G. erotoides is a junior subjective synonym of Deilephila eras Boisduval, 1832, in d'Urville, Voyage de Découvertes de l'Astrolabe (Faune ent.) 1: 185, which is a subspecies of Sphinx erotus Cramer, 1777, Uitlandsche Kapellen (Papillons exot.) 2: 12, pl.104, fig.B.
Gnathothlibus erotoides was again proposed as a new species by Wallengren, 1860, Wien. ent. Monatschr. 4: 43; and as a new genus and a new species in 1861, K. Svenska Fregatten Eugenies Resa ... C.A. Virgin 1851-53 2 (Zool.) (1, Insecta): 362, pl.7, fig 4.
Kitching & Cadiou (2000) list CHROMIS Hübner, 1819 as a junior name of GNATHOTHLIBUS Wallengren, 1858.
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