BugWise

What do cockroaches look like?

An example of a cockroach. Photo: © B Hulbert.

Cockroach. Illustration: A Howells © Australian Museum.

Size:

3 mm - 70 mm in length.

Body:

Oval, flattened as if pressed from above.

Segment behind head shield-like, overhanging body and often covering base of head.

Appears hard.

Antennae:

Thread-like, length variable.

Eyes:

Large and well separated.

Cave-dwelling cockroaches may have reduced or no eyes.

Mouthparts:

For chewing or munching.

Held downwards at rest.

Wings:

Two pairs if present.

Forewings are hardened and cloudy.

Hindwing membranous and clear.

Both wings lack cross veins and are of similar size.

At rest, wings are held flat to body, with forewings overlapping, and hindwing hidden.

Limbs:

Six legs with many spines.

Slender designed for running.

Abdomen tip:

Two cerci (tails) never longer than the body and have one or more segments.

Where are cockroaches found?

• They are adaptable to most environments.
• The majority of Australian natives are found amongst leaf litter, under bark and rocks, and within rotting logs and crevices.
• Others live in trees or underground in burrows or caves.
• Introduced species are often found in the house.

What do cockroaches do?

• They often group together sometimes in large numbers, but are usually solitary.
• When disturbed they runaway, usually undercover and fast; rarely fly.
• They are weak fliers, usually flying in short bursts.
• Introduced species feed on plant or animal debris; native species primarily feed on plant debris.
• Most are active at night, however some do openly bask in sunlight.

What looks similar?

• Beetles can be distinguished from cockroaches by their hardened forewings. These forewings, or rather elytra, never overlap but meet in the middle. Beetles also never possess cerci.