The effects of male harassment on mating duration in the seed bug,Togo hemipterus

Harassment on mating pairs by solitary males is usually considered an attempt by the male to (1) take over the female, (2) guard the female against further insemination (when the solitary male has previously copulated with this female), or (3) influence mating duration. Paired males of a seed bug repel harassment on mating pairs by solitary males by firmly grasping females using their legs and/or genital claspers; in this way, mating duration is prolonged. Male fertilization success increases as mating duration increases. Males of the seed bug, Togo hemipterus (Scott) (Heteroptera: Lygaeidae), use seminal substances to inhibit female remating. These substances induce protracted female refractory periods and are transferred to the females in a time‐dependent manner. Consequently, mating duration has important effects on fitness in this species. We observed harassment on T. hemipterus mating pairs by solitary males, and examined conflicts between paired and solitary males over mating duration. None of the solitary males were able to take over a mating female, and this may be due to the unique male genital structure in this species. All conflicts over mating duration resulted in wins by the paired males over the solitary males. Paired males prolonged mating durations, whereas severe harassment on mating pairs by solitary males shortened durations. We show that even though there is no immediate reward for the solitary male (i.e., it is unable to take over the mating female), this harassment behavior may be adaptive.