The ecology of female receptivity in the territorial butterfly Hypolimnas bolina (L.) (Nymphalidae): implications for mate location by males

Many male insects aggressively defend specific perching sites containing la rval resources. There are three main explanations for how this behaviour co uld contribute to increased matings: perching males may aim to encounter (1 ) eclosing or freshly eclosed virgin females, (2) previously mated, oviposi ting females, or (3) receptive females that visit these sites either specif ically to mate or for other reasons. I evaluated these hypotheses by invest igating the timing of post-eclosion female receptivity and the extent of po lyandry within an Australian population of the butterfly Hypolimnas bolina (L.) (Lepidoptera: Nymphalidae). This species represents the group of butte rflies in which males defend specific, geographically prominent, sites that overlap with the distribution of larval resources. Freshly emerged female H. bolina refrained from mating until their ovaries were close to maturatio n, resulting in a pre-mating period of 4-8 days. The presence of this subst antial refractory period rules out the hypothesis that males defend pupatio n sites with the aim of mating with eclosing or freshly eclosed females. Se condly, almost 90% of females within the studied population carried only on e spermatophore, a finding that mediates against the possibility that most perching males target (already mated) ovipositing females. The 'rendezvous- site' hypothesis is the most likely general explanation for territoriality in H. bolina; however, it remains unclear whether the distribution of larva l hostplants per se has a primary influence on territory selection by males in this species.