How do katydids make sounds with their wings?

Katydids produce their characteristic rasping songs through a process called stridulation, which involves rubbing their forewings together.12

The mechanism relies on specialized structures located on the wings:
* The File: One forewing features an enlarged vein with a row of serrated teeth.32
* The Scraper: The opposite forewing has a sharp edge that acts as a scraper.32

During sound production, the insect lifts its wings at an angle—typically between 15° and 40°—and rapidly opens and closes them, shuffling the file across the scraper. This action causes the wing membranes to vibrate, creating sound specifically during the closing motion. The rhythm, repetition rate, and natural resonances of these vibrations determine the unique song of each species. While males are the primary sound producers, some species in the subfamily Phaneropterinae engage in duets where females respond to male calls with ticking sounds.321