Abstract
Larvae of the bruchid beetle Caryedes brasiliensis (Bruchidae) develop entirely within the seed of the neotropical legume Dioclea megacarpa. The seed contains an appreciable concentration of L-canavanine, a potent antimetabolite and structural analog of L-arginine. This bruchid beetle uses the nitrogen stored in this toxic allelochemical as an effective dietary nitrogen source for amino acid biosynthesis.