AUDITORY RECEPTOR ORGANS IN THE FORELEGS OF GAMPSOCLEIS-GRATIOSA (TETTIGONIIDAE) - MORPHOLOGY AND FUNCTION OF THE ORGANS IN COMPARISON TO THE FREQUENCY PARAMETERS OF THE CONSPECIFIC SONG

The morphology and the physiology of the auditory receptor organs in the forelegs of the tettigoniid species Gampsocleis gratiosa were investigated in detail. According to the tonotopic organization of the receptor cells of the crista acoustica in bushcrickets the threshold curves of all receptors found in the organs were correlated with the morphology of the auditory receptor cells. This was done by arranging them in relation to their frequency tuning with the receptors along the chain of cells in both organs starting proximally with the extreme low frequency cell up to the highest ultrasonic cells at the distal end of the crista acoustica. This investigation reveals that the auditory receptor organs of Gampsocleis gratiosa possess a broad banded hearing threshold curve including very low frequency parts. Also the conspecific stridulatory song is very broad banded with extraordinarily low frequency components. Therefore the sender and the receiver of this species-specific communication system seem to be well adapted to each other. (C) 1993 Wiley-Liss, Inc.