Jerusalem Cricket (Potato Bug)

Stenopelmatus fuscus — the common Jerusalem cricket — is one of about 30 species in family Stenopelmatidae and one of the strangest and most-encountered nocturnal arthropods in the western US. The species is widespread across the western US (especially California, Oregon, Washington, Nevada, Arizona) and northern Mexico. Adults are 5-7 cm body length, flightless, with the species' diagnostic appearance: a HUGE BULGING HEAD that is disproportionately large compared to the body and looks unsettlingly HUMAN-LIKE in its smooth dome shape and large dark forward-facing eyes; a barrel-shaped striped abdomen with alternating black-and-tan bands; six powerful walking legs (no specialized jumping legs despite being a 'cricket'); and a heavy beige-to-brown body coloration that resembles a smooth potato. The species is widely known as the 'POTATO BUG' (because the bulging head and segmented body look like a small potato with legs) or 'CHILD OF THE EARTH' ('NIÑO DE LA TIERRA' in Mexican Spanish — the species figures prominently in Mexican folk tradition, which holds that the species cries like a baby and is a sign of bad luck). The Jerusalem cricket is NOT a true cricket (family Gryllidae) and not from Jerusalem — the common name origin is unclear and possibly a corruption of an indigenous word or a misunderstanding of an early European naturalist's labels. The species lives UNDERGROUND in burrows during the day and emerges at night to hunt small arthropods, decaying organic matter, and roots. Jerusalem crickets produce two distinctive sounds: a CREEPY-SOUNDING SCRATCHING/CHIRPING produced by rubbing the abdomen against the hind legs (the species is one of the few non-true-cricket Orthoptera that stridulates), and a low DRUMMING that males produce by tapping the abdomen against the substrate to call females (similar to the percussive mating calls of click beetles and some moths). Mating involves a remarkable behavior: females sometimes EAT THE MALE after copulation (sexual cannibalism similar to some mantis and spider species), though the post-mating cannibalism is not consistent across populations. Despite the intimidating appearance and folklore, Jerusalem crickets are COMPLETELY HARMLESS to humans — no venom, no sting — but the species can deliver a STRONG NIP with the powerful mandibles if forcibly handled. The species is one of the most-photographed and most-Googled bugs in California natural history, with seasonal social-media attention every autumn when adult Jerusalem crickets become active and start showing up in basements, garages, and around pool decks across the west.