Mantis shrimp hurl their legs with incredible speed during these blows, which is nontrivial considering they are underwater. Sheila Patek and Roy Caldwell, studying the mechanics of the predatory strike of the peacock mantis shrimp, found that they accomplish this feat using a "click" mechanism in which a rigid latch locks the limb into a spring-loaded and cocked position. When this lock is released, the weapon snaps forward using elastic recoil from energy stored in the bending of the skeleton, exactly like releasing the recoil stored in a fully drawn archer's bow. Once released, their legs blaze through the water at strike speeds of up to sixty miles per hour which, when scaled down to the size of these "shrimp," means that the entire strike takes just two one-thousandths of a second.

Emlen, Douglas J, Animal Weapons_ The Evoluti…, loc. 119