Cardiac glycosides (heart poisons) in the polka-dot moth Syntomeida epilais Walk. (Ctenuchidae: Lep.) with some observations on the toxic qualities of Amata (= Syntomis ) phegea (L.)

Syntomeida epilais sequesters and stores several cardiac glycosides from its food plant Nerium oleander L. Unlike the other insects previously examined which feed on oleander, this moth stores oleandrin in its body tissues. Amata phegea, feeding on non-poisonous plants, contains a histamine-like substance which increases capillary permeability in rats. Both species are repellent to many avian predators. The predilection shown by several Ctenuchids, and the related Arctiids, for foodplants containing cardiac glycosides or pyrrolizidine alkaloids is discussed.