Identification
The four species of
Periplaneta cockroaches found in the US are easily confused. See the distinguishing characteristics of these species on the
Periplaneta page.
Adults have wings and will occasionally fly. However, they are awkward fliers and prefer to run when disturbed. Males and females are about the same size and look very similar. Both have a pair of cerci, finger-like appendages, at the tips of their abdomens. The cerci are used to detect air currents in the cockroach's surroundings. In American cockroaches, the cerci are long and tapered which helps to distinguish it from other Periplaneta species.
Male cockroaches have an additional set of appendages called styli on their abdomens. The styli are located between the cerci but are smaller and more delicate. The presence of styli is the easiest way to distinguish male from female cockroaches.
Immature American cockroaches resemble adults, except they are wingless.
The American cockroach egg capsules are mahogany brown and about 1/3 inch long.
Remarks
They are significant pests throughout the world. They are not native to the Americas at all. They come from tropical Africa. They were probably transported to the Americas on slave ships.
Coprophagy is essential for establishment of gut microbes in first-star nymphs and distributing these gut microbes among group members.
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