Electronic techniques for measuring insect behavior in the laboratory.

ARS-4

The ultrasonic mating signal of the male lesser wax moth

Abstract. Male lesser wax moths, Achroia grisella (Fabricius) (Lepidoptera: Pyralidae: Galleriinae), produce both a pheromone and an ultrasonic acoustic signal that function in mate attraction. We describe the structure of the acoustic signal, in particular the interpulse intervals and the spectral properties of the pulses. The song consists of a train of ultrasonic pulses. The interpulse interval is usually bimodally distributed, but can sometimes be unimodal. This reflects variation in the duration of the up and down wing strokes. The pulses are also usually paired which can produce multimodality of the interpulse intervals. These paired pulses probably reflect wingbeat asynchrony because they are not found in males in which the signalling capability of one wing's sound producing structure is abolished. The song's frequency spectrum has peaks at around 80 and 100 kHz. The first peak varies significantly with male size, with larger males producing a lower frequency peak. The second peak is associated with male age, with 1‐day‐old males producing songs with a lower frequency second peak. Thus the ultrasonic song of lesser wax moths is more complex in structure than previously reported and could provide potentially important cues to females. However, the ability of females to discriminate such detail is not known.</p