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.
Portunidae is a family of crabs which contains the swimming crabs.
Majidae is a family of crabs, comprising around 200 marine species inside 52 genera, with a carapace that is longer than it is broad, and which forms a point at the front. The legs can be very long in some species, leading to the name "spider crab". The exoskeleton is covered with bristles to which the crab attaches algae and other items to act as camouflage.
Parthenopidae is a family of crabs, placed in its own superfamily, Parthenopoidea. It comprises nearly 40 genera, divided into two subfamilies, with three genera incertae sedis:
Palaemon is a genus of caridean shrimp of the family Palaemonidae. The conventional circumscription of the genus Palaemon is probably paraphyletic. Molecular data suggest that Palaemonetes, as well as the genera Exopalaemon and Couteriella, are nested within Palaemon. Phylogenetic affinities in these groups correspond better with geographical origin than conventional genus assignments.
Osachila is a genus of crabs in the family Aethridae, containing three fossil species, and the following extant species:
Leucosiidae is a family of crabs containing three subfamilies and a number of genera incertae sedis:
Microcassiope is a genus of crabs in the family Xanthidae, containing the following species:
Micropanope is a genus of crabs in the family Xanthidae, containing one exclusively fossil species and the following species:
Paraxanthias is a genus of crabs in the family Xanthidae, containing one exclusively fossil species and the following extant species:
Pandalus is a genus of shrimp in the family Pandalidae. Members of the genus are medium-sized and live on or near the seabed. Some species are the subject of commercial fisheries and are caught by trawling. One species, Pandalus montagui, lives in association with the reef-building polychaete worm, Sabellaria spinulosa.
Pilumnus is a genus of crabs, containing the following species:
Pisinae is a subfamily of crabs in the family Epialtidae, comprising the following genera:
The Panopeidae are a family containing 26 genera of morphologically similar crabs, often known as "mud crabs". Their centers of diversity are the Atlantic Ocean and eastern Pacific Ocean.
Pyromaia cuspidata, also known as the dartnose pear crab, is a species of crab in the family Inachoididae. This crab appears similar to Anasimus latus. It is a long-legged crab with a trident-shaped rostrum, and occurs in Atlantic waters from North Carolina to west Florida, and in the Gulf of Mexico through the Yucatán Peninsula down to Nicaragua. It is also found in Cuban waters. This species lives in depths of 27–549 metres (89–1,801 ft) on bottoms of mud, sand, or pebbles.
Anasimus latus is a species of crab in the family Inachoididae.
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.
Rochinia is a genus of crab in the family Epialtidae, containing the following species:
Euryplacidae is a family of crabs in the superfamily Goneplacoidea which consists of 14 existing genera and 31 existing species and 8 fossil genera and 15 fossil species.
Heptacarpus is a genus of shrimps in the family Thoridae. There are more than 30 described species in Heptacarpus.
