Mating strategy of spider mite, Tetranychus urticae(Acari: Tetranychidae) males: Postcopulatory guarding to assure paternity.

Abstract

Precopulatory guarding behavior in males of Tetranychus urticae occurs because only the first mating is effective for females. Sufficient copulation duration to fertilize females in the laboratory is shorter than it is in nature. This finding leads to the hypothesis that the copulation duration of T. urticae is prolonged by postcopulatory guarding which prevents the female from remating with other males. To test this hypothesis, we manipulated the interval between the first and second copulations of a female. A significant positive correlation was detected between the mating interval and the proportion of daughters fathered by the first male of each brood. Males using postcopulatory guarding are successful when other males disturb the mating pair to take over from the mating male. These results demonstrate that males gain from prolonged copulation that prevents a female from remating until their sperm precedence is assured. Thus, males of T. urticae increase their paternity not only by precopulatory guarding but also by the postcopulatory guarding.