The German cockroach is the most important species found in the US. It is about 12-17 mm long as an adult. Nymphs and adults of both sexes have two dark stripes behind the head.

It prefers to live in kitchens and bathrooms of homes and apartments, restaurants, etc.

The Asian cockroach, Blattella asahinai, appears identical to this roach but is found outdoors living in lawns and leaf litters.