PYRROLIZIDINE ALKALOIDS IN ARTIFICIAL NECTAR PROTECT ADULT ITHOMIINE BUTTERFLIES FROM A SPIDER PREDATOR

Larvae of most neotropical ithomiine butterflies feed on plants containing solanaceous alkaloids. Adults visit flowers or rotting parts of palnts containing pyrrolizidine alkaloids. Extracts made from wild caught adult ithomiines inhibit feeding by Nephila clavipes, a large orb-weaving spider, while extracts from larval food plants do not. In feeding experiments with the ithomiine Episcada salvinia, most wild caught adults are rejected by N. clavipes, but laboratory reared larvae, pupae and freshly emerged adults fed sucrose solution are not. Moreover, some adult male and female E. salvinia were chemically protected and unpalatable to N. clavipes when fed a sucrose solution containing heliotrine, a pyrrolizidine alkaloid. Freshly emerged adults exposed to flowers of plants repotted to produce pyrrolizidine alkaloids may also gain unpalatability to N. clavipes. -from Author