Why Does a Cockroach Moult?

A cockroach moults in order to shed its old skin. The process takes days to weeks. After the nymphs have grown and developed their first exoskeleton, they begin to molt. New skin must be grown so the cockroach can break out of its shell. This new skin is called the cuticle and helps the cockroach retain moisture.

Cockroaches undergo seven to eight molts before reaching adulthood. Each time they molt, they shed their old skins to grow into their adult bodies. This process is known as ecdysis. After each molt, cockroaches develop a new shell and become more similar to their adult counterparts. Their nymphs start out with a white cuticle and grow a new, dark brown cuticle shortly afterward.

The adult cockroach develops wings during the final molt. Once it becomes an adult, it cannot get these wings back. However, it’s easy to mistake a cockroach’s wings with those of another insect. Unlike other insects, cockroaches do not tear off their own wings. Rather, they lose them when they are attacked.

A cockroach nymph is born from an old shell and undergoes several molts. Each molt allows the pest to grow a little more than before. The nymph stage lasts between 55 and 68 days and includes about six or seven molts. It also has reproductive organs.