The oviposition of unfertilized eggs depends on the presence of potential mates in a kissing bug

Abstract In most species, females face the risk of losing their oocytes if they remain unmated for a prolonged period. However, it remains unclear whether they have developed mechanisms to prevent the loss of fertilizable eggs according to the chances of finding a mate. We predict that virgin females will lay a lower proportion of their produced eggs when they perceive the presence of a male conspecific. We tested this prediction in the kissing bug Rhodnius prolixus, comparing the oviposition of virgin females randomly exposed to the presence of a potential mate or isolation over 10 d. We found that isolated females laid 3 times as many eggs as females exposed to the presence of a male. The dissection of females showed that both groups produced similar numbers of developed eggs, suggesting that differences in oviposition are due to changes in egg retention, rather than on egg production. We discuss the possible benefits of egg retention in virgin females, and how this process may contribute to their reproductive decision-making.