female to mate appears to be rather short, limited to only about three days. The females of this species are not guaranteed to mate, and it has been estimated that around 14% of females never mate. Female mating success is correlated with population size, where reduced female mating success was observed at low population densities, and greater success at higher population densities. However, other studies have suggested that female mating success decreases as density increases, possibly due to male-male competition for mating. Mating behavior The species has no courtship. Rather, males simply dive on a female upon finding her and force her down to the ground if she is not already there, and forcibly attempt to mate. This is successful if she has not already mated, but usually unsuccessful if she has already mated, due to a mating plug, a small waxy plug deposited onto a female's abdomen by a male to prevent future copulation. Unsuccessful matings may last an hour or more before the female escapes. If a female is unreceptive to mating, she may close up her wings tightly when a male approaches in an attempt to avoid being seen. Nuptial gifts After copulation, the male deposits a waxy genital plug on the tip of the female's abdomen, a mating plug, to prevent the female from mating again. It contains sperm and nutrients for the female. This ensures that the male is the only one to fertilize the female's eggs. Occasionally, the mating plug is not properly deposited, which means a mated female may sometimes present with no plug, or a mated male may present with a plug retained in his claspers. However, no difference has been shown in the number of eggs laid by females with and females without a mating plug, indicating that male-donated nutrients play a negligible role in female fecundity. This suggests that in this species, the plug's primary role is to prevent the female butterfly from mating multiple times. Oviposition Oviposition, or the laying of eggs occurs around the host plant Sedum lanceolatum, but not on the host plant itself. Females tend to search for good-quality meadows that have S. lanceolatum, though high host plant density is not required. They will retain their eggs and travel greater distances to find suitable meadows before oviposition. It is likely that there is some chemical or physical cue from the larval host plant that stimulates the