Contact Chemoreception Guides Oviposition of Two Lauraceae-Specialized Swallowtail Butterflies (Lepidoptera: Papilionidae).

摘要

Females of Papilio iroilus Linnaeus and Papilio palamedes Drury (Lepidoptera: Papilionidae), two closely related swallowtail butterflies, oviposit almost exclusively on a few woody plant species in the family Lauraceae. While geographic patterns of preference differ among Lauraceae species, the butterflies rarely oviposit on any plant species outside the Lauraceae. The role of host plant chemistry in stimulating oviposition was assessed by extracting the preferred host foliage of the respective butterfly species, spraying the extracts and fractions on various substrates, and assessing oviposition relative to controls. P. troilus and P. palamedes were stimulated to oviposit on filter paper or non-host leaves sprayed with polar extracts of their primary host plants, indicating clearly that leaf chemistry, detectable as contact chemosensory cues, plays a significant role in their oviposition choices. Dependence on chemical oviposition elicitors found only in the foliage of the host plants may explain the behavioral fidelity to Lauraceae shown by these two oligophagous butterflies.