Reproductive behavior of Thyanta pallidovirens (Heteroptera: Pentatomidae)

Abstract

Reproductive behavior of the stink bug Thyanta pallidovirens (Stål) was studied in the laboratory, including the determination of the sexual maturation period for both sexes, the effects of the number of copulations on fecundity, and the function of prolonged copulation. Mean premating periods for males and females were 3.6 ± 0.5 and 4.1 ± 0.6 d, respectively. Preoviposition period averaged 6.6 ± 0.9 d. Females preferred sheltered, rough-textured oviposition sites. Paired adults mated ≈ 13 times on average during their lifespan under laboratory conditions. The mean duration of copulations involving virgin females was >17 h, significantly longer than that of subsequent copulations, which lasted between 6.9 and 8.3 h. Multiple matings significantly increased female fecundity. Virgin males donated ≈ 17% of their body mass to a virgin female during mating. Duration of mating may be regulated by space available in the spermatheca for ejaculatory material. There was strong evidence of male mate choice, with males terminating copulation with small females before sperm was transferred. There was no indication of male mate-guarding behavior after copulation. Females almost always approached males from distances of >30 cm, suggesting that males attract females from a distance. Within 15 cm, males discern and approach females. Courtship behaviors of males included antennation of female antennae and abdomens, stroking the abdomens with the hind legs, and periodic male abdominal vibrations. Possible functions of these behaviors are discussed.