PROCESSING OF IRIDOID GLYCOSIDE ANTIRRINOSIDE FROM MAURANDYA-ANTIRRHINIFLORA (SCROPHULARIACEAE) BY MERIS-PARADOXA (GEOMETRIDAE) AND LEPIPOLYS SPECIES (NOCTUIDAE)

The iridoid glycoside antirrinoside was found to be sequestered by highly aposematic larvae of the geometrid moth Meris paradoxa and two noctuid moth Lepipolys species feeding on Maurandya antirrhiniflora (Scrophulariaceae), a natural food plant from southern Arizona. The antirrinoside content of leaves and petioles being consumed, early-instar larvae, late-instar larvae, larval frass, regurgitant, reflex-bleeding emission (Meris paradoxa), cocoons, pupae, meconium emitted upon eclosion, and adult moths was determined. Larvae, other than the earliest instars, did not excrete antirrinoside in the frass, but sequestered it in amounts of 3-11% of the dry weight. Small amounts of antirrinoside remained in various pupal or cocoon parts and some was emitted in the meconium upon eclosion. The total antirrinoside accounted for was, however, considerably below that expected based upon the remarkably high 20% content of the leaves and petioles being consumed. The adult cryptic moths of both species contained little or no antirrinoside. This is the first report of a natural food plant and larval stages for M. paradoxa and a previously undescribed Lepipolys species. It is also the first report of antirrinoside sequestration and utilization by insects.