What has stridulatory organs?

Stridulation is the act of producing sound by rubbing together certain body parts. This behavior is mostly associated with insects, but other animals are known to do this as well, such as a number of species of fish, snakes and spiders.

Insects and other arthropods stridulate by rubbing together two parts of the body. These are referred to generically as the stridulatory organs. The mechanism is best known in crickets, mole crickets, and grasshoppers.

The mechanism is typically that of one structure with a well-defined lip, ridge, or nodules (the "scraper" or plectrum) being moved across a finely-ridged surface (the "file" or stridulitrum—sometimes called the pars stridens) or vice versa, and vibrating as it does so, like the dragging of a phonograph needle across a vinyl record.