The main sound producing apparatus in singing cicadas is a pair of tymbals, positioned in the lateral parts of the first abdominal segments. In addition to this, some cicadas produce sounds also by other means, often associated with wing movements. To get a better insight into the wing clicking mechanism in Cicadatra persica and Pagiphora anullata we used a commercial high-speed digital video camera JVC GR-DVL 9800E. With this camera one can fill each frame on the tape with 2 or 4 smaller subframes and after deinterlacing extract two half-frames from each. This corresponds to an 8x final recording speed and is adequate for a recording frequency of 200 frames per second. For such analyses we used a Digital Origin EditDV computer program and Adobe Photoshop 5 software. To compare sound tracks with corresponding image sequences we exported sound clips from EditDV to Canary 1.2. Oscillograms were subsequently transferred to Photoshop 5 for comparison. Selected video clips were exported from EditDV to Photoshop as image sequences, which were subsequently deinterlaced, sorted and inserted into the same picture for comparison of sound and video tracks. Since there exists a systematic delay between both tracks we had to shift the video track backwards for 21-23 ms. After this correction we analysed our video recordings of Cicadatra and Pagiphora specimens to associate sounds with specific wing movements. From this information we made conclusions about the sound producing mechanism. Nevertheless, some additional experiments with other methods are needed to prove the conclusions.
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