Acoustics; Vibration; Chorusing; Behaviour; Defense; Larvae; Icosium; Cerambycidae; Coleoptera

Substrate-borne vibrations produced by the larvae of non-lamiinae longicorn Icosium tomentosum Lucas, 1854 (Cerambycidae: Cerambycinae) are also emitted as loud sounds audible to humans. The vibrations consists of a long sequence of regularly repeated pulses at a rate of 8 pulses per second. The duration of the pulses are 0.061 +/- 0.009 s and the interpulse intervals are 0.065 +/- 0.015 s. The mechanism of vibration generation is the scraping by strongly sclerotised mandibles against the bark. Chorusing behaviour previously unknown in Cerambycidae larvae have been observed when the larvae feeding in the same or nearby branches starting to produce the audible vibrations in reaction to the vibrations of another larva.