Carcinus is a genus of crabs, which includes Carcinus maenas, an important invasive species, and C. aestuarii, a species endemic to the Mediterranean Sea.
Mictyris is a genus of brightly coloured crabs, placed in its own taxonomical family, the Mictyridae. It inhabits the central Indo-West Pacific region. These crabs congregate on mud flats or beaches in groups of a few thousand, and filter sand or mud for microscopic organisms. They congregate during low tide, and bury themselves in the sand during high tide or whenever they are threatened. This is done in wet sand, and they dig in a corkscrew pattern, leaving many small round pellets of sand behind them.
Belliidae is a family of crabs of the order Decapoda.
Discoplax is a genus of terrestrial crabs. It is very closely related to the genus Cardisoma.
Discoplax rotunda is a species of land crab in the genus Discoplax found in the Pacific Ocean.
Johngarthia is a genus of crabs in the land crab family Gecarcinidae, formerly included in the genus Gecarcinus, and containing the following five species:
Ucides is a genus of mangrove crabs in the monotypic family Ucididae, containing two species:
Pseudozioidea is a superfamily of crabs, formerly treated in the Eriphioidea, Carpilioidea, Xanthoidea, Pilumnoidea and Goneplacoidea. A number of fossils from the Eocene onwards are known from the family Pseudoziidae. Eleven genera are recognised in three families:
Bellia picta is a species of crab that lives around the coasts of South America, and the only species in the genus Bellia. On the Atlantic coast, it is found in Rio Grande do Sul, Brazil, while on the Pacific coast, it is found off Peru and Chile. It probably lives in burrows and is a filter feeder.
Karstarma is a genus of karst-dwelling crabs formerly included in Sesarmoides.
Hemus is a genus of spider crab in the family Majidae. It contains four species:
Pilodius is a genus of crabs in the family Xanthidae, containing the following species:
Paraetisus globulus is a species of crab in the family Xanthidae, the only species in the genus Paraetisus. It was described in 1933 by Charles Melbourne Ward.
Heteractaea is a genus of crabs in the family Xanthidae, containing the following species:
Monodaeus is a genus of crabs in the family Xanthidae, containing the following species:
Polydectus cupulifer is a species of crab in the family Xanthidae, and the only species in the genus Polydectus. Together with the genus Lybia, it forms the subfamily Polydectinae. It is found in the Indo-Pacific, ranging from Madagascar and the Red Sea in the west to Japan, Hawaii and French Polynesia in the east. P. cupulifer is densely covered with setae (bristles), and frequently carries a sea anemone in each chela (claw).
Cycloxanthops is a genus of crabs in the family Xanthidae, containing the following species:
Demania is a genus of crabs in the family Xanthidae, containing the following species:
Johngarthia weileri is a species of land crab in the genus Johngarthia from the eastern Atlantic Ocean.
Pilumnoides inglei is a species of crab, known only from a few specimens collected on derelict boats on the south coast of England.
