Question-mark cockroach

Therea olegrandjeani

Size: Up to 3 cm.
Lifespan: Up to 3 years. 
Food: Dead plant parts, fruit. 

Markings resembling question marks

With a little imagination, you might be able to see how the question-mark cockroach got its name? On the wings, it has a black and white pattern, which could resemble question marks. The species has a close relative, which is black with white dots – it is called the domino cockroach. Both species are believed to use their appearance to resemble other, more dangerous, species of insects. It is a strategy called mimicry, and it is used as a kind of protection or defence.

It is believed that the pattern on the question mark cockroach serves as a deterrent for animals that may want to eat the insect.
Photo: Nandini-Rajamani-CC-BY

Living a short life as an adult

The question-mark cockroach is an Indian species of cockroach. It is quite small, flat and round when fully grown. However, it spends most of its life as a small nymph, buried in the soil and feeding on dead plant parts. After a couple of years as a nymph, it has grown and become an adult. Then it is time for a short life above ground, about a year, where it likes to eat fallen fruit from the ground. During the mating season, the females lay lots of egg capsules, containing 20-30 eggs each. She lays the eggs protected under leaves on the ground, and they hatch after a few months. Shortly after reproduction, both the male and female die.

The cockroach lives its short adult life on the ground, primarily feeding on fallen fruits.
Photo: B-a-y-L-e-e-s-8-Legged-Art-CC-BY-SA

Distribution worldwide

South India

Threat based on the Red List

Trade regulations

CITES: Not listed.