Chemical Identity of Cuticular Lipid Components in the Mimetic Swallowtail Butterfly Papilio polytes

Abstract

The swallowtail Papilio polytes shows Batesian and female-limited polymorphic mimicry. In Japan, P. polytes females have two different forms: the cyrus form is non-mimetic and resembles males, whereas the polytes form mimics Pachliopta aristolochiae and Byasa (Atrophaneura) alcinous as unpalatable models. During mating, P. polytes males use cuticular lipids to distinguish non-mimetic females from conspecific males and sympatric sister species. In this study, we investigated whether compositional differences in cuticular lipids exist between mimetic and non-mimetic females of P. polytes and between mimetic females and their model species. The mimetic and non-mimetic females had nearly identical cuticular lipid profiles, which differed from those of males. The two model species exhibited sexually dimorphic and species-specific cuticular lipid compositions, which were distinctly different from those of mimetic P. polytes females. These results strongly suggest that P. polytes females maintain the identity of cuticular lipid profiles regardless of the mimicry type, and this feature helps males recognize mimetic females as the correct mating partners.

The scent chemistry of butterflies

“…194,196 Males of P. polytes use cuticular hydrocarbons for mate discrimination to distinguish non-mimetic females from conspecific males and sympatric sister species, certain alkenes serving as behavioural inhibitors of male copulation. 198…”