Female choice for male gregariousness in a Stink bug,Megacopta punctissimum (Montandon) (Heteroptera,Plataspidae)

Adults of a stink bug,Megacopta punctissimum, form mating aggregations on their host plants, based on the gregarious habit of males. A female was released on a stem on which there was an aggregation of 2 mating pairs and 1 bachelor male. Next, the bachelor male was released on a stem on which no bugs were present, and the same female was released there. Sequences of courtship behavior were compared between them. This experiement was repeated for 41 pairs of males and females, and about half (20 cases) of these experiments were made in the reverse order. Males were the active sex in courtship, whilst females either accepted the courtship, or escaped from courting males. Females accepted courtship with a higher probability when males courted in aggregations (73%) compared to solitary conditions (22%). This was because the escape behavior of females from the males was reduced if females detected the presence of other bugs near the males. It was concluded that female choice is a selective force for gregariousness in males.