Household bug guides

Structured field notes, not listicles. Check lookalikes before you treat — or start from a photo.

Identify 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.