Journal of insect behavior vol:10 issue:2 pages:289-298
We studied the mating system of the emerald damselfly Lestes sponsa. All 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 mate guarding: (1) a high female receptivity after copulation, (2) a high male capacity to resist takeovers, (3) sperm precedence, (4) a high operational sex ratio, (5) a high male density, (6) high access by rivals to mated females, (7) low energy expenditure, (8) a low risk of guarding, and (9) a short interval between copula and oviposition. This indicates a positive cost-benefit balance for this behavior, at least in males. A comparison within the genus Lestes suggests that the male-biased sex ratios and the ease with which mated females are detected have been strong selection pressures in the evolution of intense contact mate guarding.