Tegminal amplifiers and spectrum consistencies in Conocephalus nigropleurum (Bruner), Tettigoniidae

doi:10.1016/0022-1910(67)90109-6

Journal of Insect Physiology

Volume 13, Issue 7, July 1967, Pages 1075-1085

https://doi.org/10.1016/0022-1910(67)90109-6 Get rights and content

Abstract

The sound frequency spectrum of Conocephalus nígropleurum (Bruner) was investigated with two different models of a custom-built analyser. The spectrum is continuous from 0 to 100 kc/s and contains a band of markedly more intense frequencies extending from 28 to 60 kc/s. When sufficient care was taken to eliminate variation due to microphone-insect alignment, this band or intensity aggregate was found to be highly consistent in the amplitude of its component frequencies.

The proximal portions of the tegmina contain modified cells. Tearing these cells produced a large reduction in intensity over the entire spectrum but failed to alter the location and shape of the aggregate. It is concluded that the tegminal wing cells function exclusively as amplifiers. The vein network is suggested as a structural source of the aggregate. A cantilever model is used to represent probable vein oscillation.

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Citation Excerpt :
A sharp lobe on the right wing (the scraper) is swept upon a vein lined with precisely arranged cuticular teeth on the left wing. A large specular wing cell (adjacent to the scraper) on the right wing, the so-called mirror, subsequently couples the low amplitude vibrations, produced by this initial file-scraper interaction (Bailey and Broughton, 1970; Broughton, 1964; Morris, 1999; Morris and Pipher, 1967; Robinson, 1990) to the air. A particular characteristic of the acoustic signals in the genus Typophyllum is that the calls of the males exhibit a very sharp spectrum with high Q and that most species known so far communicate at about 20 kHz (Braun, 2002, 2015a,b; Montealegre-Z and Morris, 1999; Morris et al., 1989) (Q = quality factor, which describes the properties of a damped resonator or oscillatory system (Bennet-Clark, 1999b)).
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^∗: Present address: Syracuse University Research Corporation, Syracuse, New York

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Tegminal amplifiers and spectrum consistencies in Conocephalus nigropleurum (Bruner), Tettigoniidae

Abstract

J. Insect. Physiol.

Function of the mirror in tettigonioid Orthoptera

Nature, Lond.

The physical characteristics of sound emissions in arthropoda