Reproductive Behavior of Paraglenea fortunei (Coleoptera: Cerambycidae)

Abstract

The daily reproductive activity patterns, reproductive behavior, and stridulation of the beetle Paraglenea fortunei Saunders were studied. There are two activity peaks in walking/flying (0600-1400 hours and 1500-2100 hours) during the day. The peaks for feeding, mating, and ovipositing are 1400-2100 hours, 0800-1500 hours, and 1400-2000 hours, respectively. Feeding and mating usually occur on the upper sections of the plants. The female oviposits in the stem up to 3 cm above ground level and never deposits her eggs where eggs have been deposited by another. Within 10 cm two individuals can communicate through substrate-borne vibrations produced by feeding or walking. A male can discern the sex of another individual from just within 5 cm. Before mating the male always approaches the female, who therefore seems to possess a sex pheromone. Mating may be terminated if the female performs a rejection display on her own initiative, or if another male disturbs the mating pair. Our interpretation of the male's stridulation is defensive behavior, aggressive behavior, a complicated form of courtship display with some slight threat, and a calming of the female to make continuous copulation possible. The female's stridulation may be significant as defensive behavior, rejecting the male's courtship, and a signal for termination of copulation.