THE ADAPTIVENESS OF INTENSE CONTACT MATE GUARDING BY MALES OF THE EMERALD DAMSELFLY, LESTES SPONSA (ODONATA, LESTIDAE) - THE MALES PERSPECTIVE

We studied the mating system of the emerald damselfly Lestes sponsa. A ll males showed intense contact mate guarding by holding the female in tandem during the entire oviposition period. Our findings support the predictions made by Alcock (1994) about the occurrence of intense mat e guarding: (1) a high female receptivity after copulation, (2) a high male capacity to resist takeovers, (3) sperm precedence, (4) a high o perational sex ratio, (5) a high male density, (6) high access by riva ls to mated females, (7) low energy expenditure, (8) a low risk of gua rding, and (9) a short interval between copula and oviposition. This i ndicates a positive cost-benefit balance for this behavior, at least i n males. A comparison within the genus Lestes suggests that the male-b iased sex ratios and the ease with which mated females are detected ha ve been strong selection pressures in the evolution of intense contact mate guarding.