The purpose of this application, under Article 23.9.3 of the Code, is to conserve the name Papilio hesperus Westwood, 1843 (Lepidoptera, papilionidae) for a well-known species of butterfly. In 1995 it was proposed to ask the Commission to suppress Papilio hesperus Fabricius, 1793 (Lepidoptera, nymphalidae) in order to conserve Papilio hesperus Westwood, 1843 (Lepidoptera, papilionidae), but a formal application was never made. The senior name has not otherwise been used except as a junior synonym of Papilio daedalus Fabricius, 1775, or in inconclusive discussions, for 200 years or more. Accepting its seniority would be very disruptive to taxonomic stability of butterfly names in much of the African rainforest zone. The suppression of Papilio hesperus Fabricius, 1793 for the purposes of both the Principle of Homonymy and the Principle of Priority would coincidentally also serve to conserve the name Harma chalcis C. & R. Felder, 1860, which is in widespread use in much of Africa in the combination Euryphura chalcis.