The Australian cockroach (Periplaneta australasiae) is a common species of tropical cockroach, with a length of 23–35 mm (0.91–1.38 in).It is brown overall, with the tegmina having a conspicuous lateral pale stripe or margin, and the pronotum (head shield) with a sharply contrasting pale or yellow margin. It is very similar in appearance to the American cockroach and may be easily mistaken for it. It is, however, slightly smaller than the American cockroach, and has a yellow margin on the thorax and yellow streaks at its sides near the wing base.