Jerusalem crickets (genus Stenopelmatus) are a group of large (body length up to 69mm), flightless insects native to the western United States, along the Pacific Coast, and south into Mexico. Because of their large, human-like head, they are commonly called niņo de la tierra (Spanish for "child of the earth"), Earth baby, cara de niņo (Spanish for "child's face"), wó see ts'inii (Navajo for "skull insect"), or old bald-headed man. They are also often called potato bugs.
Despite their name, Jerusalem crickets are neither true crickets nor true bugs and they do not prefer potatoes for food. Active only at night, the insects use their strong mandibles to feed primarily on dead organic material but can also eat other insects. Their highly adapted feet are used for burrowing beneath moist soil to feed on decaying root plants and tubers.
There are a number of other genera in same family, Stenopelmatidae, and these genera occur in Australia and New Zealand. These are the "weta" and "king crickets", and they are similar to Stenopelmatus in many respects.
The Jerusalem cricket's song features a characteristic drumming sound.
Similar to true crickets, each species of Jerusalem cricket produces a different song during mating, but this "song" takes the form of a characteristic drumming in which the insect beats its abdomen against the ground.
Most species have no sound-producing structures, and evidently none have structures they could use to hear audible sound (true crickets use their wings to produce sounds, but Stenopelmatus lack wings, and crickets and katydids have membranous "ears" they use to hear) - they do not even seem to be able to hiss by forcing air through their spiracles, as some beetles and cockroaches do. Instead, the few Jerusalem crickets which do make audible sound rub their hind legs against the sides of the abdomen, which produces a rasping, "hissing" noise; this rasping noise appears to be designed to frighten predators, rather than being used in communication between the crickets themselves. For such purposes, Jerusalem crickets apparently rely exclusively on substrate vibrations, which are felt rather than heard.
As is true for other large, "ugly" arthropods (e.g. solfugids), there are a number of folk tales regarding Jerusalem crickets which are simply untrue; first and foremost, they are not venomous. However, they can emit a foul smell and are capable of inflicting a painful bite - but neither is lethal, as some of the tales would suggest. They also do not cry like children, nor rub their legs together to make sounds.
Mahogany Jerusalem cricket (Stenopelmatus n. sp. "mahogany")