Household bug guides
Structured field notes, not listicles. Check lookalikes before you treat — or start from a photo.
- German cockroach
Blattella germanica
A small indoor cockroach, typically 13–16 mm long, light brown to tan, with two dark parallel stripes on the pronotum (the shield behind the head). It is one of the most common household cockroach species in heated buildings.
- Bed bug
Cimex lectularius
A small, oval, flattened insect that feeds on blood. Adults are about 4–7 mm, reddish-brown, and are usually found in and around beds, sofas, and other sleeping or resting furniture — not in kitchen grease films like German cockroaches.
- Carpet beetle
Anthrenus and Attagenus species
Small oval beetles whose larvae feed on natural fibers, shed pet hair, lint, and sometimes pantry goods. Adults are often seen on windowsills in spring. They are frequently mistaken for bed bugs or “tiny black bugs in the carpet.”
- Stink bug
Pentatomidae (often Halyomorpha halys indoors)
Shield-shaped true bugs with a triangle on the back. The scutellum is a triangle between the wings — it does not cover the whole abdomen the way a jewel bug’s scutellum does. In North American homes, the usual indoor nuisance is the brown marmorated stink bug, which seeks winter shelter in wall voids and rooms.
- House centipede
Scutigera coleoptrata
A fast, flattened arthropod up to about 1.5 inches long with 15 pairs of long, banded legs and long antennae. Despite its alarming look, it hunts other household pests — cockroaches, silverfish, termites, and bed bugs among them.
- Silverfish
Lepisma saccharina
A wingless, teardrop-shaped insect up to about 3/4 inch long, covered in silvery-grey scales, with three long bristles at the rear. It feeds on starches — paper, glue, wallpaper paste, and stored goods — and moves with a distinctive wiggling “swim.”
- Flea
Ctenocephalides felis (cat flea — the usual indoor species in North America)
A tiny (1.5–3 mm), wingless, laterally flattened insect that jumps and feeds on the blood of pets and people. Flea bites cluster on the lower legs and ankles in humans and around the base of the tail in pets.
- Indian meal moth
Plodia interpunctella
The most common pantry moth in North America. Adults have a two-toned wing pattern — pale near the body, coppery-brown on the outer half — and a wingspan of about 3/4 inch. Larvae infest cereals, flour, nuts, dried fruit, pet food, and birdseed.