If you’ve spotted a bug in your house with noticeably long antennae, you’re likely looking at one of five common household pests: a house centipede, a cockroach, a silverfish, a camel cricket, or a longhorned beetle. Each one is easy to tell apart once you know what to look for, and most are more of a nuisance than a genuine threat.
House Centipedes
The house centipede is often the bug that sends people straight to a search engine. Its body is only one to one and a half inches long, but with its 15 pairs of banded legs and long antennae, the whole creature looks three to four inches from end to end. The body is a dirty yellow color with three dark stripes running lengthwise, and the legs fan out to the sides in a way that makes it look much larger and more alarming than it actually is. The last pair of legs on adult females stretches to nearly twice the body length, which many people mistake for additional antennae.
House centipedes are fast. They dart across walls, ceilings, and floors at night, hunting smaller insects like spiders, bed bugs, and cockroaches. During the day, they hide in dark, damp spots: basements, bathrooms, closets, and crawl spaces. Despite their unsettling appearance, they are harmless to people. They can technically bite if handled roughly, but the common house centipede species found indoors is rarely strong enough to break human skin. Across all centipede species globally, only one to seven fatalities have ever been substantiated, dating back to 1932, and none involved the small house centipede.
Cockroaches
All cockroaches share a set of recognizable features: an oval body, a shield-like plate behind the head, spiny legs, and long thread-like antennae that can be as long as or longer than the body itself. The species you find indoors varies by region and by what part of the house the roach prefers.
The German cockroach is the most common indoor species. Adults are half to five-eighths of an inch long, golden-brown to dark brown, with two dark parallel stripes on the plate behind the head. They have wings but cannot fly. The American cockroach is much bigger, one and a half to two inches long, reddish-brown, with a yellowish margin behind the head. Both sexes have wings, and this species can fly short distances. The brown-banded cockroach is smaller and lighter brown, with two pale bands across the wings. Pennsylvania wood roaches occasionally wander inside but prefer outdoor habitats.
Cockroaches are drawn to food residue, grease, moisture, and warmth. They are nocturnal and tend to scatter when lights come on. If you’re seeing them during the day, that often signals a larger population competing for hiding spaces.
Silverfish and Firebrats
Silverfish and firebrats are small, wingless insects with a distinctive carrot-shaped body, two long antennae at the front, and three long tail-like filaments at the back. Adults are roughly half to three-quarters of an inch long. Silverfish are light gray to silver, while firebrats tend toward brown with a mottled pattern. Their flat bodies let them squeeze into remarkably thin cracks and crevices, which is why they seem to appear from nowhere.
Both are nocturnal and hide during the day. Silverfish prefer cool, damp areas like bathrooms, basements, and seldom-disturbed bookshelves. Firebrats favor warmth, gravitating toward stoves, furnaces, water heaters, and attics where temperatures reach 90°F or higher.
The real concern with silverfish isn’t a bite (they don’t bite). It’s property damage. They feed on anything containing starch or cellulose: paper, cardboard, books, wallpaper paste, cotton and linen fabrics, stored dry goods like flour and oats, and even the paper facing on drywall. The damage looks like irregular surface scraping, rough patches on fabric, and yellowing on materials they’ve revisited. A small number of silverfish may go unnoticed for years, but a larger infestation causes cumulative, real damage to belongings and building materials.
Camel Crickets
Camel crickets are the humpbacked, wingless insects that startle people by leaping unpredictably in basements and garages. They have small bodies, camouflage-brown coloring, long spindly legs built for jumping, and antennae that are dramatically longer than the body. Those antennae serve as their primary way of navigating the world. They are extremely sensitive to touch, air currents, temperature, and the presence of other crickets, compensating for the fact that camel crickets have no ability to chirp like their field cricket relatives.
Camel crickets are not just nocturnal; they actively avoid light. Outdoors, they live under rocks, logs, and leaf litter. They come indoors when conditions outside get too hot and dry, settling into basements, crawl spaces, sheds, and areas near firewood. They eat fungus, decaying plant material, and the occasional small insect. Inside, they sometimes nibble on stored papers and fabrics, but they don’t bite or sting, rarely reproduce indoors, and cause only minor damage.
Longhorned Beetles
If the bug you found has a hard shell and antennae that sweep back past its body, it’s likely a longhorned beetle. These wood-boring beetles are half an inch or larger, narrow-bodied, and sometimes metallic in color. Their antennae can be as long as or longer than the entire body, which is the feature that gives the family its name.
Longhorned beetles are almost always associated with firewood brought inside. The larvae develop inside wood, and the warmth of your home can trigger adults to emerge, leaving small oval or D-shaped exit holes in the bark. They don’t infest finished lumber or furniture (with rare exceptions like the Asian longhorned beetle). The simplest fix is to store only a day or two of firewood indoors at a time.
Why These Bugs End Up in Your Home
Nearly all long-antennaed household pests share one preference: moisture. Damp basements, leaky pipes, humid crawl spaces, and condensation around windows create the conditions these insects need to survive. Moisture supports the growth of mold and fungus, which directly feeds silverfish, camel crickets, and many small beetles. Cockroaches and centipedes are drawn to the same humid, secluded spaces.
Entry points are predictable. Gaps around utility pipes, electrical conduits, imperfections in construction, spaces under doors, and sliding glass doors on slab foundations all give ground-level pests easy access. Attic pests enter through vents, gaps under shingles, and cracks in eaves. Once inside, wall voids that stay damp for extended periods become highways connecting rooms, basements, and attics.
How to Reduce and Prevent Them
Controlling moisture is the single most effective step. A dehumidifier in your basement or crawl space makes the environment far less hospitable. Fix leaking pipes, improve ventilation in bathrooms and attics, and avoid letting water pool near your foundation. Many of these pests simply cannot survive in dry conditions.
Beyond moisture control, seal the entry points: caulk gaps around pipes and conduits, install door sweeps, repair torn screens, and close cracks along the foundation. Reduce clutter in basements, garages, and storage areas. Cardboard boxes, old newspapers, and piles of fabric are both food and shelter for silverfish and camel crickets. Switching to plastic storage bins eliminates two attractants at once.
For cockroaches specifically, sanitation matters as much as moisture. Clean grease from behind stoves, store food in sealed containers, and take garbage out regularly. Sticky traps placed along walls and in corners can help you gauge how many you’re dealing with and where they’re traveling. If you’re seeing cockroaches during daylight or finding them in multiple rooms, the population is likely large enough to warrant professional treatment.
House centipedes, on the other hand, are often a sign that other pests are present, since centipedes are predators that follow their prey indoors. Solving the underlying moisture and pest problem typically solves the centipede problem too.