A cyanoglucoside stored by aSedum-feeding Apollo butterfly,Parnassius phoebus

Abstract

Abstract.A bitter tasting cyanoglucoside, sarmentosin, was isolated from an aposematic Apollo butterfly, Parnassius phoebus, and from its plant-host, Sedum stenopetalum. The content of sarmentosin in the body tissues was as high as 500 ~tg/insect, suggesting a defensive role for this substance; a high concentration was detected in the wings. Sarmentosin was also present in the eggs.Key words. Parnassius phoebus; Apollo butterfly; Papilionidae; Sedum; defense substance; cyanoglucoside; sarmenrosin; sequestration.A clue to the nature of a long sought-after deterrent, assumed to be present in the aposematic (warningly coloured) Apollo butterflies, was provided by the Mag- The genus Parnassius (Papilionidae) has been described as a relic of the glacial epoch. P. phoebus inhabits sub-Alpine situations at around 1500 m and above. The specimens one of us (R. Nishida) collected in Washington State, in the U.S., were flying in high mountain meadows where one of its host-plants, Sedum stenopetalum (Crassulaceae), was exceedingly common. In Europe, Sempervirum montanum (Crassulaceae) and Saxifraga aizioides (Saxifragaceae) are recorded as its food plants 3. The butterfly exhibits classical warning colouration, both the dorsal surface and underside being strikingly aposematic.We originally examined P. apollo, since in Europe it feeds exclusively on stonecrop (Sedum spp.), but only preserved specimens were available, which proved unsuitable for the detection of sarmentosin. Fresh material was unobtainable, since the insect is declining in numbers and strictly protected. It is of historical interest that P. apollo was the first butterfly to be officially protected; this was achieved by the efforts of the Emperor of Germany, William I, and it was thereafter included under the Convention of International Trade in Endangered Species of Wild Fauna and Flora (CITES) 4. Materials and methodsAdults of P. phoebus were captured at a field site in Washington State (Kittitas County) in mid-June 1994.* To whom correspondence should be addressed.Ten males were immediately extracted with ethanol (20 ml) and kept below 0 ~ After removing the first extract, the body tissues were finely ground and re-extracted with a mixture of benzene and ethanol (1:2, 10 ml x 2). The combined extracts (159 rag) were subjected to solvent extraction with chloroform and water. The water layer (28 rag) was chromatographed on a reverse-phase column (Sep-pak cartridge C18, Waters Associates), by eluting successively with water (2 ml + 2 ml), 20% methanol (3 ml) and 50% methanol (4 ml). The bitter component was found mainly in the second 2 ml water-eluate (4 mg) after elution of the initial 2 ml of water. Portions of the second eluate were purified by high performance liquid chromatography (HPLC) with YMC-Pack ODS-AM (150 x 6ram i.d.) eluting with 3% methanol (1.5 ml/min), monitored by a photodiode array detector (2200 400 nm). The compound was isolated at a retention time of 6.5 min. A similar analytical procedure was employed for the detection of the compound in ...

Chemical ecology of insect–plant interactions: ecological significance of plant secondary metabolites

“…As predicted, sarmentosin was detected in a substantial quantity in adults of Parnassius apollo in Europe and in P. phoebus in the Rocky Mountains in the USA. 42,48) Thus, the secret of their aposematic life style both as larvae and adults can be explained by sermentosin, although any potential predators and the actual defensive roles of the compound remain to be clarified. Ericaceae-feeding moth-grayanoid diterpenes.…”

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

“…Other butterflies (e.g., Danaus plexippus L. (Nymphalidae) (Brower & Glazier 1975), Parnassius phoebus (Fabricius) (Papilionidae) (Nishida & Rothschild 1995), Eumaeus atala (Poey) (Rothschild et al (1986)) contain at least as high a concentration of sequestrants in the wings as in the body. Beak-mark patterns on the wings of unpalatable butterflies indicate that they can survive attack by birds without vital injury (Carpenter 1941).…”

“…Toxic Lepidoptera appear quite commonly to place sequestrants on their eggs. These include cardenolides in Danaus plexippus ), cyanoglucosides in Parnassius phoebus (Nishida & Rothschild 1995), and pyrrolizidine alkaloids in various Arctiidae and danaine and ithomiine Nymphalidae (Brown 1987;Dussourd et al 1989;Nishida et al 1991). The latter deter coccinellid and chrysopid larvae (Bogner & Eisner 1991), which are typical predators of papilionid eggs as well.…”

Using Coalescent Simulations to Test the Impact of Quaternary Climate Cycles on Divergence in an Alpine Plant‐insect Association

“…Both species exhibit low dispersal (Clausen 1975;Keyghobadi et al 1999Keyghobadi et al , 2005, isolation among populations, and geographic structure associated with known biogeographic provinces in the Rocky Mountains (Keyghobadi et al 1999;DeChaine andMartin 2004, 2005a). Sedum lanceolatum produces a cyanogenic glycoside, sarmentosin, as a secondary defensive compound that deters herbivores, but the caterpillar of P. smintheus feeds exclusively on S. lanceolatum and sequesters the toxin for its own protection (Sperling and Kondla 1991;Nishida and Rothschild 1995). Furthermore, the adult butterfly of P. smintheus pollinates the flowers of S. lanceolatum (Scott 1973;Clausen 1975).…”