Conocephalus Anisoptera dorsalis

The males stridulate for most of the day, with a song that superficially resembles that of the long-winged conehead. The sound is produced in prolonged, continuous bursts, but the more high-pitched 'chugging' (described as a 'hiss' by those who can hear it without the aid of a bat detector) alternates at irregular intervals with a lower-pitched 'clicking' sound (see DVD). This may be produced by alternately speeding up and slowing down the rate of vibration of the tegmina. [1]

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