This little black native cockroach is often mistaken as a juvenile of the larger Maoriblatta novaeseelandiae. It is distinguished by its reddish tip to the antennae and stronger reddish tinge to the legs. It is much more uncommon than its relative and is found mainly under kanuka or very young kauri (pole kauri), or within the dried fronds and leaf bases of treeferns. It has not been found in urban or horticultural habitats, unlike the very similar introduced Australian black roach Tryonicus parvus. Both males and females have very short remanants of tegmina (the upper, non-functional stiff wings) and the distal halves of the antennae are distinctly reddish-brown.