Sequestration of aristolochic acids by the pipevine swallowtail, Battus philenor (L.): evidence and ecological implications

Abstract

It has long been assumed that the North American pipevine swallowtail, Battus philenor (L.) (Papilionidae, Troidini), is protected from natural enemies by aristolochic acids sequestered from its Aristolochia food plants. This study confirmed that populations of B. philenor from Virginia and east Texas sequester these compounds. A comparison of the aristolochic acid profiles of the Virginia butterflies and their A. macrophylla food plants revealed several differences. The aristolochic acid fraction of the foliage was dominated by aristolochic acids I and II, whereas the insects had a much lower proportion of aristolochic acid II and contained, in addition, substantial amounts of aristolochic acids Ia and IVa, which were not detected in the plants. The eggs, larval integument, osmeterial glands, pupal cuticle, and adults (wings and bodies) all contained aristolochic acids. These findings help explain the abundant ecological data indicating that both immature and adult B. philenor are unpalatable and protected from natural enemies.

A within-species warning function for an aposematic signal

“…Aristolochic acids are highly toxic to vertebrates and insects (Brower & Brower 1964;Chen & Zhu 1987;reviewed in Sime et al 2000;Sime 2002). B. philenor larvae sequester aristolochic acids, and all life stages of the species contain them (Sime et al 2000). Larvae offered to wolf spiders and paper wasps are refused (Bernays 1988;D.…”

Aristolochic acids affect the feeding behaviour and development of Battus polydamas archidamas larvae (Lepidoptera: Papilionidae: Troidini)

“…Larvae of the genus Battus (Papilionidae, Troidini) are able to sequester aristolochic acids from their host-plants. The compounds remain in the body of the larvae and are transferred to the adults and their progeny (Sime et al, 2000;Nishida, 2002;Fordyce et al, 2005). Aristolochic acids are used in defence and in selecting oviposition sites by this genus of butterflies (Fordyce, 2000;Nishida, 2005).…”

Use of volatiles of Aristolochia chilensis (Aristolochiaceae) in host searching by fourth-instar larvae and adults of Battus polydamas archidamas (Lepidoptera: Papilionidae: Troidini)

“…Dispersing larvae need to find other host-plants and continue feeding. The fourth instar larvae seem to have developed the sensory system necessary for them to be able to recognise a host-plant, and at that point, they may have also sequestered sufficient AAs in their tissues (Sime et al, 2000) to deter predators.…”