It has been shown experimentally that in endowing the eggs, the female resorts not only to her own PA but also to a portion of the PA received from the male ( 4).įor laboratory testing, spiders were taken in vials and transferred singly into cylindrical plastic containers (17-cm diameter 11-cm height with a shallow bottom layer of sand), to which the spiders adapted quickly. In addition to sperm and a quantity of nutrient that the female invests in egg production ( 7), the spermatophore contains PA. Mating in Utetheisa involves transfer from male to female of a sperm package (spermatophore) of considerable size, amounting on average to over 10% of male body mass ( 6). Notably, the PA in the eggs do not stem entirely from the mother moth. All developmental stages of the moth are protected as a result: the larvae and adults against spiders ( 2, 3) and the eggs against ants and ladybird beetles ( 4, 5). Females also transmit PA to their eggs ( 1). It sequesters the PA as a larva from its food plants (Fabaceae Crotalaria spp.) and retains the chemicals through pupation into adulthood. The moth Utetheisa ornatrix (Lepidoptera: Arctiidae henceforth referred to as Utetheisa) depends on pyrrolizidine alkaloids (PA) for defense.

Utetheisa ornatrix rle