The adult dung beetle Aphodius ater(De Geer) stridulates at a very low
intensity. The morphology of the stridulatory apparatus was analysed
with the scanning electron microscope. This apparatus is abdomino-alar
y with the plectrum on the abdomen scraping against the pars stridens
on the hind wings. The stridulation was recorded as vibrations on the
elytra of the beetles by laser vibrometry. The single syllables, 40-85
ms each, are repeated with a frequency of 7-11 Hz. The vibrations are
transmitted over a distance of a few millimeters in sheep dung, the n
atural habitat of the beetle. The stridulation can be elicited either
by disturbance or by the presence of a conspecific within the dung.