Information-based or resource-based systems may mediate Cycas-herbivore interactions.

Invasive arthropod herbivores comprise one of the greatest threats to cycad conservation both in situ and ex situ. We discuss two mechanisms, not necessarily mutually exclusive, that may underlie the disparity in Chilades pandava damage among Cycas species. In an information-based system, plant infochemicals may differentially influence oviposition behavior of Ch. pandava adults or host finding behavior of this butterfly's natural enemies. Alternatively, heterogeneity in damage may be mediated by a resource-based system whereby plant substrate is more palatable to larvae for susceptible species or more defended by less damaged species.