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.
Libinia is a genus of crabs in the family Epialtidae, containing twelve extant species:
Libystes is a genus of crabs, containing six species:
Maja is a genus of majid crabs erected by Jean-Baptiste Lamarck in 1801. It includes the following extant species:
Cancridae is a family of crabs. It comprises six extant genera, and ten exclusively fossil genera, in two subfamilies:
Belliidae is a family of crabs of the order Decapoda.
Gecarcinucoidea is a superfamily of freshwater crabs. Its members have been grouped into families in various ways, with some authors recognizing families such as "Deckeniidae", "Sundathelphusidae", and "Parathelphusidae", but now only the family Gecarcinucidae is currently recognized.
Menippe is a genus of true crabs. One of the best known species is the Florida stone crab. Most of the species of this genus are found in the Atlantic Ocean.
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.
Panopeus is a genus of crabs, containing these extant species:
Ptychophallus is a genus of crabs in the family Pseudothelphusidae.
Medaeus is a genus of crabs in the family Xanthidae, containing the following species:
Cyrtocarcinus truncatus is a species of crab in the family Xanthidae that lives in the waters around Hawaii. It was described in 1906 by Mary J. Rathbun as Harrovia truncata, based on a single immature male specimen caught near Kauai. Masatsune Takeda transferred the species to his new genus Glyptocarcinus in 1979, and Peter Ng and Diana Chia erected a new genus, Cyrtocarcinus, for this species alone, in 1994.
Pseudomedaeus is a genus of crabs in the family Xanthidae, containing the following species:
Cataleptodius is a genus of crabs in the family Xanthidae, containing the following species:
Garthiope is a genus of crabs in the family Pseudorhombilidae, containing the following species:
Gonopanope is a genus of crabs in the family Pseudorhombilidae, containing the following species:
Leptodius is a genus of crabs in the family Xanthidae, containing the following species:
Micropanope is a genus of crabs in the family Pseudorhombilidae, containing one exclusively fossil species and the following species:
Inachoididae is a family of crabs originally erected by James Dwight Dana in 1852. It was not recognised as a valid family until the early 1980s. Its members closely resemble those of the family Inachidae, and the Inachoididae could be recognised as a subfamily of that family.
