The original mechanism of vari-toned song production in Mingming cicada (Oncotympana maculaticollis Motsch)

On the basis of a study on the fundamental property of vari-toned song in the Ming-ming cicada, the original mechanism of the sound production is further analysed in this paper.
In the Mingming cicada, each single call consists of the prelude, loud song containing some vari-toned syllables ‘Wéiying’ and coda. Each vari-toned syllable is composed of ‘Wéi’ with the basic sound (BS) as the dominant tone and ‘ying’ with the upper partials (UP₂) as the dominant tone, and the upper partials (UP₁) is a sound accompaniment of low intensity. The BS, UP₁ and UP₂ are produced by vibrations of the long ribs LR₂, LR₃ and LR₁ in the sounding membrane driven by twiches with different properties in the sounding muscle, respectively.
The LR₁ and LR_2,3 may be analogous to a string tensioned on two ends and a beam hinged on two ends with a load in the middle, respectively. In analogical models, the acoustic properties of sounding vibration are not only suited to the structural characteristics of LR_1,2,3 but also consist basically with the acoustic properties of the song.