Host plant suitability and chemistry of virgin tiger moth, Grammia virgo L. (Erebidae: Arctiinae)

Larvae of the Arctiinae use an impressive arsenal of defenses to protect themselves against natural enemies. Several species within this subfamily have been studied for their defensive capabilities, specifically the use of plant secondary metabolites. Life history and sequestration patterns of secondary metabolites have been well documented for one species, Grammia incorrupta; however, little information exists for other species of Grammia. Furthermore, information on sequestration patterns during the life cycle from egg to pupa is largely unknown. To address these gaps, I am conducting a comparative study of life history traits for the virgin tiger moth (Grammia virgo), the little virgin tiger moth (Grammia virguncula) and the figured tiger moth (Grammia figurata) throughout larval development, along with investigating sequestration patterns of secondary metabolites from different species of host plants. Larvae were divided into three host plant treatment groups: clover (Trifolium repens), broadleaf plantain (Plantago major), and narrowleaf plantain (Plantago lanceolata); an artificial diet served as a control for these treatments. I collected data on development time for each instar, larval weight at each instar and overall survivorship. A subset of larvae was also harvested at each instar; these samples were prepared for chemical analysis. Here I present results of the feeding trials along with observations of feeding behavior. I will also discuss plans for future work including further comparisons of secondary metabolite sequestration patterns observed with analytical chemistry.