Blue Swimmer Crab Description
The males are bright blue in colour with white spots and with characteristically long chelipeds, while the females have a duller green/brown, with a more rounded carapace. The carapace can be up to 20 centimetres wide.
It may grow up to 150 millimetres long, and may weigh up to 900 grams. The carapace is wider at the front, reddish brown in color, with ten white spots. Ranina ranina is mainly nocturnal, and remains buried in the sand during the day. Ranina ranina is easily distinguished from other crab species in its habitat due to its red carapace and elongated midsection