Pyrrolizidine alkaloids sequestered by Solomon Island Danaine butterflies. The feeding preferences of the Danainae and Ithomiinae

The plant sources and identity of pyrrolizidine alkaloids sequestered by six species of Solomon Island Danainae have been investigated. The secretions of the pheromone‐disseminating hairpencils of the males have also been analysed and the componenets, including pyrrolizidine metabolites, have been identified. The first confirmed example of Danaine larvae, rather than adults, acquiring pyrrolizidine alkaloids is reported and its relevance to hypotheses concerning the origin of the requirement of Danaine and Ithomiine butterflies for pyrrolizidine alkaloids is discussed.