Effects of male body size on mating behavior and female mate refusal in the white-spotted longicorn beetle, Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae)

Abstract

In the white-spotted longicorn beetle, Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae), body size shows a large diversity both in males and females. We compared behavioral responses of different sizes of males to intact females and glass-rod models treated with female extract. Holding, mounting and abdominal bending responses to females were more frequently observed in small males than in large ones. Furthermore, small males showed these behaviors in response to lower doses of female extract than did large ones. However, females refused small males more frequently than large males, and approached the latter more frequently. This suggested that small males have high sensitivity to female sex pheromone that may offset the disadvantage of lower preference by females.