Cockroaches

All species

• American CockroachPeriplaneta americanaTake care
• Brown-banded CockroachSupella longipalpaTake care
• German CockroachBlattella germanicaTake care
• Madagascar Hissing CockroachGromphadorhina portentosaHarmless
• Oriental CockroachBlatta orientalisTake care

Start with a photograph

Identify an insect from a photo. The result includes confidence, common lookalikes and a plain safety assessment; read its accuracy and limits before treating a low-evidence photo as definitive.

Which one you have, in about ten seconds

Size and the plate behind the head do almost all of it, and where you found it confirms the answer. This is worth getting right before spending any money, because treatment aimed at the wrong species reliably fails.

• Small, tan, two dark stripes running back from the head — German. Lives in kitchens; the one that infests.
• Small, with pale bands ACROSS the body — brown-banded. Lives in dry warm rooms and furniture.
• Large, glossy reddish-brown, pale figure-of-eight behind the head — American. Comes up from drains.
• Large, very dark, slow, almost wingless — Oriental. Cool damp basements, and it cannot climb well.
• Very large and completely wingless with horns — Madagascar hissing cockroach, a pet that cannot live here.

One large roach is a different problem from three small ones

The instinct on seeing a big cockroach is that things are bad, and it is usually backwards. A single large American cockroach at night near a bathroom has almost certainly come up a drain — it is a route problem, fixed with water in the trap and a sealed pipe collar. Small tan roaches with stripes, especially wingless striped nymphs, mean German cockroaches breeding on site, and that is the serious finding whatever the size. Nymphs are the signal worth acting on, not the dimensions of the adult.

Common questions