Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting tail-like abdomen, usually hidden entirely under the thorax. They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers on each arm. They first appeared during the Jurassic period, around 200 million years ago.
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.
Latreilliidae is a small family of crabs. They are relatively small, long-legged crabs found on soft bottoms at depths of up 700 metres (2,300 ft) in mostly tropical and subtemperate waters around the world. Their carapace is very small and doesn’t cover the bases of their legs, which protrude from the cephalothorax in a spider-like manner. The family and its type genus are named after Pierre André Latreille. The oldest known fossils from the Latreillidae have been dated to the middle of the Cretaceous period. It comprises seven extant species.
Pilumnus hirtellus, the bristly crab or hairy crab, is a species of European crab. It is less than 1 inch (25 mm) long and covered in hair. It lives in shallow water and feeds on carrion.
Xantho hydrophilus, the furrowed crab or Montagu's crab, is a species of crab from the family Xanthidae. It is yellowish-brown and grows to a carapace width of 70 mm (2.8 in). It is a nocturnal omnivore that lives in shallow marine waters from western Scotland to the Cape Verde Islands.
Xantho is a genus of crabs in the family Xanthidae, containing five extant species, all restricted to the north-east Atlantic Ocean and Mediterranean Sea, although Xantho granulicarpis is not universally recognised as a separate species from Xantho hydrophilus:
Zosimus aeneus, also known as the devil crab, toxic reef crab, and devil reef crab is a species of crab that lives on coral reefs in the Indo-Pacific from East Africa to Hawaii. It grows to a size of 60 mm × 90 mm and has distinctive patterns of brownish blotches on a paler background. It is potentially lethal due to the presence of the neurotoxins tetrodotoxin and saxitoxin in its flesh and shell.
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.
Guinotellus melvillensis is a species of crabs in the family Xanthidae, the only species in the genus Guinotellus. It is a benthic crab with an ovate carapace within the subfamily Euxanthinae.
Atergatis is a genus of crabs in the family Xanthidae, containing the following species:
Dyspanopeus sayi is a species of mud crab that is native to the Atlantic coast of North America. It has also become established outside its native range, living in Swansea Docks since 1960, the Mediterranean Sea since the 1970s, the North Sea since 2007 and the Black Sea since 2010. It can reach a carapace width of 20 mm (0.8 in), and has black tips to its unequal claws. It feeds on bivalves and barnacles, and is in turn eaten by predators including the Atlantic blue crab, Callinectes sapidus. Eggs are produced from spring to autumn, the offspring reach sexual maturity the following summer, and individuals can live for up to two years. The closest relative of D. sayi is D. texanus, which lives in the Gulf of Mexico; the two species differ in subtle features of the genitalia and the last pair of walking legs.
Carpilius maculatus, common names seven-eleven crab, spotted reef crab, dark-finger coral crab, and large spotted crab, is a species of crab in the family Carpiliidae, which also includes C. convexus and C. corallinus. While there have reports of the C. maculatus as being poisonous, biochemical testing has revealed that they lack any paralytic shellfish toxins.
Lissocarcinus orbicularis, common names sea cucumber crab, red-spotted white crab, and harlequin crab is a species of crab in the family Portunidae. This species gains one of its names from its close-knit relationship with holothuroids, the sea cucumbers. L. orbicularis should not be confused with L. laevis, a similar species of swimming crab, or Camposcia retusa, both of which are also commonly referred to as the harlequin crab. L. orbicularis displays numerous morphological and social adaptations for feeding and has a large distribution throughout the Indo-West Pacific.
Atergatis subdentatus, also known as the red reef crab, dark-finger coral crab or eyed coral crab, is a species of crab in the family Xanthidae.
Plotosus lineatus, commonly known as the striped eel catfish, is a species of eeltail catfishes belonging to the family Plotosidae. Like most other members of the genus Plotosus, they possesses highly venomous spines that they can use to sting when threatened. The venom can cause mild to severe symptoms in humans. P. lineatus is native to the Indo-Pacific but has become introduced to the Mediterranean via the Suez Canal as a Lessepsian migrant.
Cymo melanodactylus, the furry coral crab, is a species of small decapod crustacean in the family Xanthidae. It is found in the Indo-Pacific Ocean and lives in crevices and on the surface of corals in the genus Acropora.
Dyspanopeus texanus is a species of crab known as the Texas mud crab.
Atergatis floridus, the floral egg crab, green egg crab, pancake crab, or shawl crab, is a species of tropical Indo-Pacific crab from the family Xanthidae. The meat of this crab is toxic, even if cooked, and consumption often results in death.
Actea savignii is a species of Indo-Pacific crab from the family Xanthidae which is one of the spiny-legged rock crabs. It has colonised the Levantine Sea by Lessepsian migration through the Suez Canal from the Red Sea since the mid 2000s.
Gothus is a genus of crab in the family Xanthidae, known from the Indo-West Pacific. The genus comprises two species, Gothus consobrinus and the type Gothus teemo.
