Males prefer virgin females, even if parasitized, in the terrestrial isopod .

In many species, males increase their reproductive success by choosing high-quality females. In natural populations, they interact with both virgin and mated females, which can store sperm in their spermatheca. Therefore, males elaborate strategies to avoid sperm competition. In the terrestrial isopod , females can store sperm and produce several clutches. Moreover, this species can be parasitized by , which feminizes genetic males, transforming them into functional females. Our study compared attractiveness and mate choice when a male is exposed to both virgin and experienced females (i.e., females who have produced offspring and rested for 6 months), with or without . Our results revealed that males are more attracted to virgin females than experienced females, even if these virgin females are parasitized. Moreover, the chemical analysis highlighted different odors in females according to their reproductive and infection (free or vertically -infected) status. Males attempted copulation more frequently and for longer with virgin females, even if -infected, while experienced females refused further copulation. The evolutionary consequences of both male choice and female resistance on their fitness are discussed in this study.