Chemical communication in mate location and recognition in the white-spotted longicorn beetle, Anoplophora malasiaca (Coleoptera: Cerambycidae)

Abstract

The mating sequence has been studied in the white-spotted longicorn beetle, Anoplophora malasiaca (Thomson) (Coleoptera: Cerambycidae). Both females and males are attracted to wounded host plant Citrus unshiu, and adults of both sexes, and both female and male elytra contained the sesquiterpenes that were identical with those in C. unshiu. Moreover, at close range orientation by males, some visual cues derived from females acted synergistically with olfactory factors. And, female contact sex pheromone was isolated from female elytra and revealed to consist of eight hydrocarbons, four ketones, and three lactones. The mating sequence of A. malasiaca was roughly considered to occur as follows. Emerged adults from trunks of the host plants must search for their mates over large areas. Highly mobile males may be attracted from long distances by the signal of sesquiterpenes released from wounded host plants which indicate the presence of other individuals and serve for intraspecific communication in A. malasiaca. At close range orientation, the sesquiterpenes also act as attractant for both females and males, and then visual cue guided them to their mates or rivals. After a male orients to another individual, he identifies it as a mate or a rival. Once a male recognizes a female, mating occurs.