A New Genus of Andean Katydid with Unusual Pronotal Structure for Enhancing Resonances

Katydids sing with their exoskeleton, making sound waves in air by moving a scraper on their wings to and fro upon a row of teeth (file). Scraper-tooth events excite thin cuticular diaphragms of the wing called specula, causing these to vibrate and generate sound waves. In a newly identified genus of katydids from western South America, Tectucantus n. gen., this strigin (see text) as the basic organ of ensiferan sound generation, extends to adaptive acoustic loading of adjacent body parts such as the pronotum, by creating acoustic semichambers. Different pronotal shapes load specula in Tectucantus to three different degrees and may be supposed to come about through resonance -- the tuning of a body part to improve signal power.