left: dorsal view, right: ventral view

iPhoto by Hori, April 18, 2004: leg. Hori, 23 March, 2004 at Kabira, Ishigakij

Aristolochic acids (AAs) are nitrophenanthrene carboxylic acids derived from benzylisoquinoline alkaloids and found exclusively in the pipevine family, Aristolochiaceae. AAs exhibit various pharmacological activities in vertebrates. Many Aristolochiaceae feeding swallowtail butterflies in the tribes Troidini and Zerynthiini sequester AAs in their bodies. In particular, troidines that are models in a variety of mimicry complexes are highly unacceptable to various insectivorous birds. AA I acts as a feeding deterrent for a bird predator. However, predator responses to troidines may not be due entirely to AAs. Larvae of pipevine swallowtails secrete an odoriferous fluid containing high concentrations of AAs from the defensive osmeterial glands. Females of some troidines coat their eggshells thickly with an AA containing mass during oviposition. Such diverse manipulation of AAs in every life stage suggests defensive potencies against a variety of enemies other than vertebrate predators. AAs function as excellent kairomonal cues for ovipositing pipevine swallowtails and for larvae seeking out host plants. The presence of these compounds insures the quality of the hosts and consequently insures protection from predators but not poisonous for the Common Rose. (after Ritsuo NISHIDA, "SEQUESTRATION OF DEFENSIVE SUBSTANCES FROM PLANTS BY LEPIDOPTERA", Annu. Rev. Entomol. 2002. 47:57”V92.)