Functional and temporal analysis of sound production in Galleria mellonella L. (Lepidoptera: Pyralidae)

Abstract

1. Pulses of 75 kHz ultrasound are produced when male greater wax moths, Galleria mellonella L. flutter their wings. These moths use this acoustical system to coordinate their pheromone release for mate calling. The conditions under which males generate the sound pulses, and the mechanism of sound production are described for G. mellonella. 2. G. mellonella generates the ultrasound when it activates sound producing mechanisms on its tegulae. Wing motion pushes down a tegular-wing coupler attached to the tegula below a tymbal. This coupler, when pushed down by the wing, activates the tymbal, causing it to buckle in and produce a sound pulse. Upon release of pressure, the tymbal snaps back to produce a second sound pulse. 3. Male G. mellonella generated sound only when close to or contacting other insects. Insects which caused males to generate sound include either male or female G. mellonella and male or female Achroia grisella. G. mellonella males did not produce sound in the presence of their natural honeybee hosts. The evidence suggests that male G. mellonella produce more sound pulses per hour each when calling in groups. 4. Male G. mellonella could be observed producing sound only under dim light, about 2 lux or less. Males begin to call shortly after sunset, with peak repetition rate frequency occurring during the first two hours. The rate decreases throughout the night, but on warmer nights some sound production continues until sunrise. The light level under which males begin calling approximates the light level within a honeybee hive. © 1986 Springer-Verlag.