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Cockroach (German)

Common Name:          German Cockroach

Scientific Name:          Blattella germanica (Linnaeus)

Class/Order/family:      Insecta/Blattodea/Blattellidae

Metamorphosis:          Incomplete

This species is found worldwide.



Small cockroach approximately 13 – 16 mm varying in colour from light brown to tan with two dark stripes from head to base of wings. The males tend to be lighter in colour than the females who are generally broader across the abdomen. Has wings and can glide but cannot fly.


Dark brown to black thorax but pale lateral margins, pale abdomen, later nymphs (after 3rd shed)have dark abdomen.

Ootheca (Egg capsule):

Yellowish brown about 6 -9mm long with width half that of length. Shape is slightly bowed and contains approximately 30 – 40 eggs.


Fast reproduction. The ootheca is carried by the female and is only deposited in a sheltered place within 1 – 2 days of hatching. During her life an average female will produce 5 ootheca.

In ideal conditions the eggs can be adults in about 55 days but the average is approximately 103 days. This means that there is the possibility of up to 6 generations a year.


Usually between 100 – 200 days.


Very small so can survive in very small cracks and crevices.the nymphs can fit into cracks of only 1mm! But adults need about 5mm. They prefer warm humid conditions.

They are very hardy and resist a lot of types of control. An average infestation is composed of mainly nymphs (approximately 75%).

They feed on virtually anything including strange things like glue and toothpaste when food is in short supply. Their preferred diet is starchy and sugary foods together with meat and fat. The nymphs will eat the moults of the adults if necessary.

They can be very hard to spot due to the fact the males sped most of their time in their harborage as do the females when carrying eggs after the first few days. The nymphs also are not active for 3 days before each moult.

Many infestations start with the cockroaches being brought into a premises either in packaging or transported from an infested premises by other means.