Cardisoma armatum is a species of terrestrial crab.
It is sometimes referred to as the (African) rainbow crab, (Nigerian) moon crab or patriot crab. Adults are sometimes labelled as soapdish crabs in the pet industry.
Cardisoma armatum originates from coastal regions of western Africa, but it also occurs inland along some deltas (e.g. the Volta river delta), and on islands such as Cape Verde.