The nominal taxon Papilio vanessa Fabricius, 1793, for long thought to be an unrecognised species of Riodinidae from the Americas, is shown to be a synonym of the West African lycaenid butterfly Liptena septistrigata (Bethune-Baker, 1903), syn. nov. Papilio vanessa is however a nomen oblitum, as it has not been applied to any recognised taxon since 1889. Thus Liptena septistrigata has priority so long as this subjective synonymy is considered valid and, within this context, L. septistrigata should be treated as a nomen protectum.