REPRODUCTIVE-BEHAVIOR OF THYANTA PALLIDOVIRENS (HETEROPTERA, PENTATOMIDAE)

Reproductive behavior of the stink bug Thyanta pallidovirens (Stal) wa s studied in the laboratory, including the determination of the sexual maturation period for both sexes, the effects of the number of copula tions on fecundity, and the function of prolonged copulation. Mean pre mating periods for mates 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 m ated approximate to 13 times on average during their lifespan under la boratory conditions. The mean duration of copulations involving virgin females was >17 h, significantly longer than that of subsequent copul ations, which lasted between 6.9 and 8.3 h. Multiple matings significa ntly increased female fecundity. Virgin males donated approximate to 1 7% of their body mass to a virgin female during mating. Duration of ma ting may be regulated by space available in the spermatheca for ejacul atory material. There was strong evidence of male mate choice, with ma les terminating copulation with small females before sperm was transfe rred. There was no indication of male mate-guarding behavior after cop ulation. Females almost always approached males from distances of >30 cm, suggesting that males attract females from a distance. Within 15 c m, males discern and approach females. Courtship behaviors of males in cluded antennation of female antennae and abdomens, stroking the abdom ens with the hind legs, and periodic male abdominal vibrations. Possib le functions of these behaviors are discussed.