SOUND PRODUCTION IN PHRYDIUCHUS-TAU (COLEOPTERA, CURCULIONIDAE)

Phrydiuchus tau Warner produces sound by the elytroabdominal method of stridulation, using a scraper (plectrum) located on the anterodorsal surface of the seventh abdominal tergite that rasps against a file (pa rs stridens) on the ventral surface of the elytra. Sound is produced w hen the posterior of the abdomen is elevated, extended, and then retra cted to strike the rigidly held elytron. Examination of the stridulato ry structures using scanning electron microscopy indicated that they a re similar in both sexes. Both sexes stridulate when disturbed, but on ly males stridulate during courtship. Spectral analysis of several tem poral and spectral features of both courtship and disturbance song typ es indicates differences in both the frequency and intensity of the so unds produced.