Xanthidae is a family of crabs known as gorilla crabs, mud crabs, pebble crabs or rubble crabs. Xanthid crabs are often brightly coloured and are highly poisonous, containing toxins which are not destroyed by cooking and for which no antidote is known. The toxins are similar to the tetrodotoxin and saxitoxin produced by puffer fish, and may be produced by bacteria in the genus Vibrio living in symbiosis with the crabs, mostly V. alginolyticus and V. parahaemolyticus.
Potamidae is a family of freshwater crabs. It includes more than 650 species and nearly 100 genera, which are placed into two subfamilies: Potaminae and Potamiscinae.
Somanniathelphusa is a genus of freshwater crabs found in southeast China, Taiwan, and southeast Asia. It includes the following species:
Geosesarma is genus of small freshwater or terrestrial crabs, typically less than 10 mm (0.4 in) across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon Islands and Hawaii.
The Varunidae are a family of thoracotrematan crabs. The delimitation of this family, part of the taxonomically confusing Grapsoidea, is undergoing revision. For a long time, they were placed at the rank of subfamily in the Grapsidae, but they appear to be closest to Macropthalmus and the Mictyridae, which are usually placed in the Ocypodoidea. It may thus be better to merge the latter superfamily with the Grapsoidea, retaining the latter name as it is older.
Pilumnoidea is a superfamily of crabs, whose members were previously included in the Xanthoidea. The three families are unified by the free articulation of all the segments of the male crab's abdomen and by the form of the gonopods. The earliest fossils assigned to this group are of Eocene age.
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:
Palicoidea is a superfamily of crabs, comprising the two families Crossotonotidae and Palicidae. Together, they contain 13 genera, including two genera in the Palicidae known only from fossils. The two families were previously treated as two subfamilies in a Palicidae of wider circumscription.
Leucosiidae is a family of crabs containing three subfamilies and a number of genera incertae sedis:
Chlorodiella is a genus of crabs in the family Xanthidae, containing the following species:
Pilodius is a genus of crabs in the family Xanthidae, containing the following species:
Paramedaeus is a genus of crabs in the family Xanthidae, containing the following species:
Tweedieia is a genus of crabs in the family Xanthidae, containing the following species:
Crosnierius 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:
Platypodia is a genus of crabs in the family Xanthidae, containing the following species:
Pilumnus is a genus of crabs, containing the following species:
Paracleistostoma is a genus of crabs in the family Camptandriidae. It used to be a member of Ocypodidae, but now the genus is reclassified. They are distributed in Singapore, west coast of Malay peninsula and Hainan, Fujian provinces in Mainland China. They are found in seawater or mud area in brink water.
Eucrate is a genus of crabs of the family Euryplacidae.
Nanhaipotamon is a genus of freshwater crabs, in the subfamily Potamiscinae, found in southern China and Taiwan. As of 2018, 18 species have been described. The genus is named after the South China Sea, for it occurs mostly in coastal areas.
