The American cockroach (Periplaneta americana), also known as the palmetto bug or waterbug, particularly in the southernUnited States, is the largest species of common cockroach, and often considered a pest. It is native to the Southern United States, and common in tropical climates. Human activity has extended the insect’s range of habitation, and global shipping has transported the insects to world ports including Tenerife, southern Spain, Greece,Taiwan, and Cape Town and Durban, South Africa.

American cockroach adults grow to an average length of around 4 centimetres (1.6 in) and about 7 millimetres (0.28 in) tall. They are reddish brown and have a yellowish margin on the body region behind the head. Immature cockroaches resemble adults except that they are wingless.

The insect can travel quickly, often darting out of sight when someone enters a room, and can fit into small cracks and under doors despite its fairly large size. It is considered one of the fastest running insects.

In an experiment carried out at the University of California, Berkeley in 1991, a Periplaneta american registered a record speed of 5.4 kilometres per hour (3.4 mph), about 50 body lengths per second, which would be comparable to a human running at 330 kilometres per hour (210 mph). It has a pair of large compound eyes each having over 2000 individual lenses thus making it a very active night animal that shuns light.