Jerusalem crickets are large, wingless, soil-dwelling insects found across western North America and Mexico that look far more menacing than they actually are. Despite their hefty build, oversized head, and powerful jaws, they pose no real danger to people. They are not venomous, they do not carry diseases that affect humans, and they have zero interest in biting you unless you grab one. Even then, while a bite can be painful because of their strong mandibles, it is medically insignificant. The alarm they cause is almost entirely a product of their unsettling appearance, which tends to catch people off guard when one turns up in a garden or basement.
Not Actually Crickets
The name “Jerusalem cricket” is misleading on both counts. These insects have no connection to Jerusalem, and they are not true crickets. They belong to the family Stenopelmatidae and the genus Stenopelmatus, which places them in the same broad order as crickets and grasshoppers (Orthoptera) but on a very different branch. True crickets chirp by rubbing their wings together. Jerusalem crickets are wingless and communicate by drumming their abdomens against the ground, a completely different mechanism. The common name likely arose from an exclamation of surprise (“Jerusalem!”) when settlers in the American West first encountered them, though the exact origin has been debated by entomologists for over a century.
They go by other names depending on where you live. In Spanish-speaking communities, they are often called “niño de la tierra,” which translates to “child of the earth,” a reference to their rounded, somewhat humanoid head and their subterranean lifestyle. In parts of the western United States, people call them “potato bugs,” though they have no special association with potatoes beyond occasionally turning up in garden soil. The variety of folk names reflects how widespread and memorable encounters with these insects tend to be.
What They Look Like
If you have never seen one before, a Jerusalem cricket can be genuinely startling. Adults are typically five to seven centimeters long, which makes them among the largest insects most people in western North America will encounter outside of a museum. Their bodies are amber to brown, with distinctive dark bands across the abdomen. The head is disproportionately large and round, with a smooth, almost skull-like appearance, which is the feature that most unnerves people. Two small, bead-like eyes sit on either side of the head, and below them are a pair of robust mandibles that look like they mean business.
Their legs are thick and adapted for digging through soil rather than jumping. Unlike grasshoppers, which have elongated hind legs built for leaping, Jerusalem crickets have stout, spiny legs that work more like shovels. They are built for life underground, and they spend the majority of their time burrowing through dirt, feeding on roots, tubers, decaying plant material, and the occasional dead insect. When they do appear on the surface, it is usually at night, which adds to the surprise factor.
Can They Bite, and Does It Hurt?
Yes, Jerusalem crickets can bite, and yes, it hurts. Their mandibles are designed to chew through tough plant roots and hard-packed soil, so they have real mechanical force behind them. If you pick one up and it feels threatened, it may clamp down, and the bite can draw blood or leave a welt. People who have been bitten often compare it to a sharp pinch or a small cut.
That said, there are a few things worth putting in perspective. First, they are not aggressive. Jerusalem crickets do not seek out humans, chase people, or bite unprovoked. You essentially have to corner one or handle it for a bite to happen. Second, there is no venom involved. Unlike spiders or scorpions that inject toxins, a Jerusalem cricket bite is purely mechanical. The only medical concern would be secondary infection from a wound that is not cleaned properly, which applies equally to any small cut or scrape. Third, the bite is a defensive last resort. A Jerusalem cricket’s first instinct when threatened is to play dead or try to burrow away, not to fight.
So while you should not casually grab one barehanded, there is no reason to panic if you find one in your house or yard. Scoop it into a container and relocate it outdoors, or simply leave it alone and it will move on.
How They Communicate by Drumming
One of the more fascinating aspects of Jerusalem cricket biology is how they communicate. Because they lack wings, they cannot produce the chirping sounds associated with true crickets and katydids. Instead, they communicate through substrate-borne vibrations: they press their abdomen against the ground and drum it rhythmically, producing vibrations that travel through the soil. These drumming patterns are species-specific, meaning different species produce distinct rhythmic signatures, and females and males use these signals to find each other for mating.
Research on their sensory biology has revealed that Jerusalem crickets have specialized vibration-detecting structures in their legs. A study examining the scolopidial organs in their tibiae found clusters of sensory cells (between 10 and 17 per organ) positioned just beneath the cuticle, ideally placed to pick up vibrations traveling through the ground surface.1PubMed Central. The scolopidial accessory organ in the Jerusalem cricket (Orthoptera: Stenopelmatidae) This means the insects are essentially using their legs as ears, detecting the drumming signals of potential mates or rivals transmitted through the earth. It is an elegant system for an animal that spends most of its life underground, where airborne sound would be useless.
The drumming patterns also play a role in species identification. Because many Jerusalem cricket species look nearly identical to the naked eye, their drumming signatures have become one of the primary tools entomologists use to tell species apart. Two populations that appear physically indistinguishable may produce completely different drumming patterns and refuse to mate with each other, making them distinct species despite their visual similarity.
Mating and the Small-Male Advantage
Jerusalem cricket reproduction has some quirks that run counter to the general pattern in the insect world. In many species, larger males tend to have a reproductive edge because they can outcompete rivals or are preferred by females. In at least one species of Jerusalem cricket, the opposite is true: smaller males are actually more successful at copulating.
Research on mating behavior in Stenopelmatus found that as the size difference between male and female increased, with the male being larger, the likelihood of successful copulation dropped sharply. A male that was about two millimeters shorter than the female had roughly a 95 percent chance of mating successfully. But when the male was about six millimeters longer than the female, the odds fell to a coin flip. And a male 14 millimeters longer than the female had only about a 5 percent chance of completing copulation. Larger males also took significantly longer to copulate when they did manage it.2BioOne Complete. Small-male mating advantage in a species of Jerusalem cricket (Orthoptera: Stenopelmatinae: Stenopelmatus)
The likely explanation is mechanical: the mating position requires the male to align with the female in a specific way, and if he is much larger, the geometry simply does not work well. This is unusual in the insect world and highlights how physical constraints, rather than behavioral preference, can shape who reproduces successfully. It also means that in Jerusalem cricket populations, there may be selective pressure keeping males relatively small compared to females, which is the reverse of what many people would expect.
A Hidden Diversity of Species
One reason Jerusalem crickets are scientifically interesting, beyond their unusual looks, is that their diversity is drastically underappreciated. Most people who encounter one assume they are all the same species, but the genus Stenopelmatus likely contains dozens of species across western North America and Mexico, many of which have never been formally described or named. Because they are nocturnal, subterranean, and look so similar externally, traditional collection methods have barely scratched the surface.
The difficulty of telling species apart visually is compounded by the fact that they are rarely encountered in large numbers. You might dig one up in your garden every few years and never realize that the one you found in Riverside, California is a completely different species from the one your cousin found in Tucson, Arizona. The drumming patterns mentioned earlier have been one of the most productive tools for resolving this puzzle, but acoustic surveys are labor-intensive, requiring researchers to capture live animals, record their vibrations, and analyze the patterns. Genetic work has also begun to reveal just how many distinct lineages are hiding under the single common name “Jerusalem cricket.” Some estimates suggest the real species count could be well over 100, though only a fraction have been formally described in the scientific literature.
This matters for conservation in a quiet way. If what looks like one widespread, common insect is actually dozens of narrowly distributed species, each occupying a small geographic range, then any individual species could be vulnerable to habitat loss without anyone realizing it is disappearing.
Hairworm Parasites and “Mind Control”
Jerusalem crickets, like many ground-dwelling insects, can be hosts to parasitic hairworms (nematomorphs), and what these parasites do to their hosts is one of the more disturbing stories in insect biology. Hairworms are aquatic as adults but need a terrestrial insect host to complete their development. The worm grows inside the cricket’s body cavity, sometimes reaching lengths greater than the insect itself. When the worm is ready to emerge and reproduce, it needs to reach water. The problem is that its host is a land-dwelling animal that avoids water.
The worm’s solution is manipulation. Infected crickets begin exhibiting a dramatic behavioral change: they actively seek out water, moving toward light sources and bodies of water in what amounts to a suicidal march. Research on this phenomenon has shown that hairworm infection fundamentally alters the cricket’s response to light, making it approach illuminated areas rather than avoid them as healthy nocturnal crickets normally would.3Oxford Academic (Behavioral Ecology). Water-seeking behavior in worm-infected crickets and reversibility of parasitic manipulation Once the cricket reaches water, the worm emerges, and the cricket may drown. But here is the twist: the behavioral manipulation is reversible. If the worm is removed before the cricket drowns, or if the cricket survives the worm’s emergence, it can recover its normal behavior and live for several months afterward. The parasite rewires its host’s decision-making temporarily, not permanently.
This kind of host manipulation is studied across many insect-parasite systems, but Jerusalem crickets and their relatives are among the most dramatic examples. If you ever see a Jerusalem cricket walking toward a swimming pool or sprinkler at night, seemingly against its own survival instincts, a hairworm may be the reason. The cricket is not making a mistake; it is being driven.
Where You Are Likely to Find Them
Jerusalem crickets are native to the western half of North America, from British Columbia down through Mexico and into Central America. They are most commonly encountered in California, the desert Southwest, and the Pacific Northwest, though their range extends into the Great Plains in some areas. They prefer loose, sandy, or loamy soil where they can dig easily, so gardens, agricultural fields, hillsides, and areas near riverbanks are common habitats.
Encounters with humans tend to happen in a few predictable scenarios. Turning over rocks or logs in your yard, digging in a garden bed, or finding one in a basement or garage during the warmer months are the typical ways people come across them. They are attracted to irrigated areas because the moisture makes the soil easier to burrow through and supports the roots and organic matter they eat. If you live in a drier climate and suddenly start watering a patch of garden regularly, you may draw them in. They are also occasionally attracted to lights at night, which can bring them onto porches or into open doorways.
There is no reason to try to exterminate them. Jerusalem crickets are beneficial soil organisms. Their burrowing aerates the ground, and their feeding on decaying organic material helps cycle nutrients. They are also prey for owls, coyotes, skunks, and other predators, so they play a role in the local food web. If you find one inside your home, the simplest approach is to slide a piece of cardboard under it, place a jar or cup over it, and carry it back to the yard.
Why They End Up in Houses
Finding a Jerusalem cricket indoors does not mean you have an infestation. These are solitary animals that do not form colonies, swarms, or nests in the way that ants or termites do. When one turns up inside, it has almost certainly wandered in by accident, usually through a gap under a door, a crack in a foundation, or an open window at ground level. They may be drawn inside by moisture or simply by the fact that the interior of a building is dark and cool, which mimics their preferred underground environment.
If you are finding them repeatedly, check for gaps around doors and windows at ground level, especially on the sides of your home closest to irrigated landscaping or garden beds. Sealing those entry points will solve the problem more effectively than any pesticide, and since Jerusalem crickets are not pests in any meaningful sense, using chemical treatments on them is both unnecessary and wasteful. They do not eat fabric, wood, stored food, or anything else in your home. They are just lost.
Commonly Confused With Other Insects
People sometimes mistake Jerusalem crickets for other large, ground-dwelling insects, particularly mole crickets and potato beetles. Mole crickets are also burrowing insects with enlarged forelegs, but they are true crickets with wings (at least in the adult stage), and they are generally smaller and more elongated. Colorado potato beetles, despite being called “potato bugs” in some regions, are small, round, striped beetles that actually damage potato crops. Jerusalem crickets share the “potato bug” nickname in some areas but are unrelated and do not damage crops in any significant way.
The most important distinction for someone worried about danger is between Jerusalem crickets and venomous arthropods. A Jerusalem cricket’s large, rounded body might briefly remind someone of a brown recluse spider or a scorpion, but even a moment’s closer inspection makes the differences obvious. Jerusalem crickets have six legs, clear segmentation with dark abdominal bands, and a distinctly insect-like body plan. They have no stinger, no fangs, and no venom glands. If you are unsure what you are looking at, the absence of a stinger or web and the presence of those characteristic banded abdominal segments are the quickest way to identify a Jerusalem cricket and stop worrying.