King crabs are decapod crustaceans in the family Lithodidae that are chiefly found in deep waters and are adapted to cold environments. They are composed of two subfamilies: Lithodinae, which tend to inhabit deep waters, are globally distributed, and comprise the majority of the family's species diversity; and Hapalogastrinae, which are endemic to the North Pacific and inhabit exclusively shallow waters. King crabs are not true crabs and are generally thought to be derived from hermit crab ancestors within the Paguridae, which may explain the asymmetry still found in the adult forms. This ancestry is supported by several anatomical peculiarities which are present only in king crabs and hermit crabs. Although some doubt still exists about this hypothesis, king crabs are the most widely quoted example of carcinisation among the Decapoda. Several species of king crabs, especially in Alaskan and southern South American waters, are targeted by commercial fisheries and have been subject to overfishing.
Anomura is a group of decapod crustaceans, including hermit crabs and others. Although the names of many anomurans include the word crab, all true crabs are in the sister group to the Anomura, the Brachyura.
Carcinisation is a form of convergent evolution in which non-crab crustaceans evolve a crab-like body plan. The term was introduced into evolutionary biology by L. A. Borradaile, who described it as "the many attempts of Nature to evolve a crab".
The Jonah crab is a marine brachyuran crab that inhabits waters along the east coast of North America from Newfoundland to Florida. Jonah crabs possess a rounded, rough-edged carapace with small light spots, and robust claws with dark brown-black tips. The maximum reported carapace width for males is 8.7 in (222 mm), while females rarely exceed 5.9 in (150 mm). It is the closest relative to the European brown crab in the Western Atlantic.
Paralomis histrix is a species of king crab, family Lithodidae. It lives at a depth of 180–400 m (590–1,310 ft) in Tokyo Bay, Enshunada and through to Kyūshū. It has few predators because of its size and spiky carapace. It is sometimes kept in public aquariums and is occasionally referred to as the porcupine crab, a name otherwise used for Neolithodes grimaldii.
Lithodes is a genus of king crabs. Today there are about 30 recognized species, but others formerly included in this genus have been moved to Neolithodes and Paralomis. They are found in oceans around the world, ranging from shallow to deep waters, but mostly at depths of 100–1,000 m (300–3,300 ft). They are restricted to relatively cold waters, meaning that they only occur at high depths at low latitudes, but some species also shallower at high latitudes. They are medium to large crabs, and some species are or were targeted by fisheries.
Calcinus tubularis is a species of hermit crab. It is found in the Mediterranean Sea and around islands in the Atlantic Ocean, where it lives below the intertidal zone. Its carapace, eyestalks and claws are marked with numerous red spots. C. tubularis and its sister species, C. verrilli, are the only hermit crabs known to show sexual dimorphism in shell choice, with males using normal marine gastropod shells, while females use shells of gastropods in the family Vermetidae, which are attached to rocks or other hard substrates.
Neolithodes is a genus of king crabs, in the family Lithodidae. They are found in all major oceans, both in high and low latitudes. Although there are records from water as shallow as 124 m (407 ft) in cold regions, most records are much deeper, typically 700–2,000 m (2,300–6,600 ft), with the deepest confirmed at 5,238 m (17,185 ft). They are fairly large to large crabs that typically are reddish in color and spiny, although the size of these spines varies depending on species.
Paralomis zealandica, also known as the prickly king crab, is a species of king crab which lives at a depth between 254–1,212 m (833–3,976 ft) in New Zealand. It has spiky carapace. The scientific name of the species was first validly published in 1971 by Dawson & Yaldwyn. P. zealandica can be distinguished from other species in New Zealand waters by its thick covering of strong upright spines all over, including on its abdomen and along its legs and claws. The rostrum has three short, strong and sharp spines. It is the most widespread species of Paralomis in New Zealand.
Neolithodes flindersi is a species of king crab found in southeastern Australia. They have been found at depths of 887–1,333 metres (2,910–4,373 ft) but typically appear from 950–1,050 metres (3,120–3,440 ft). They most closely resemble Neolithodes brodiei and Neolithodes nipponensis.
Neolithodes agassizii is a species of king crab native to the Western Atlantic. They live at depths of 200–1,900 metres (660–6,230 ft), and have been found as far south as Rio de Janeiro, as far north as latitude 36°, and near the Equator. It has been found in the southwestern Caribbean Sea as well as the Gulf of Mexico.
Neolithodes yaldwyni is a species of king crab which is found in the Ross Sea from depths of 124–1,950 metres (407–6,398 ft). It had previously been misidentified as Neolithodes brodiei, and it closely resembles Neolithodes capensis.
Neolithodes bronwynae, commonly known as the rock crab, is a species of king crab which is found at the Whakatane Seamount in the Bay of Plenty, the Lord Howe Rise near Lord Howe Island, eastern Australia, and possibly New Caledonia. It has been found at depths of 1,515–2,643 metres (4,970–8,671 ft).
Neolithodes brodiei, also known as Brodie's king crab, is a species of king crab which is native to New Zealand and its adjacent waters. It lives at a depth of 500–1,240 metres (1,640–4,070 ft) but is typically found within a depth of 950–1,150 metres (3,120–3,770 ft). It is the most widespread and common lithodid in New Zealand waters, and the New Zealand Department of Conservation classifies it as "Not Threatened".
Neolithodes vinogradovi is a species of king crab whose native habitat ranges from the Arabian Sea to the Coral Sea.
Neolithodes asperrimus is a species of king crab native to the coast of Africa. It has been found in South Africa and Mauritania at depths of 997–1,862 metres (3,271–6,109 ft), and Neolithodes aff. asperrimus has been found in Madagascar, Réunion, and the South Region of Brazil.
Neolithodes capensis is a species of king crab which is found in the Southern Ocean and the western Indian Ocean. It has been found to a depth of 660–3,200 metres (2,170–10,500 ft).
Neolithodes diomedeae is a species of king crab which is found in the eastern Pacific Ocean, the southwestern Atlantic Ocean, and the Bellingshausen and Scotia Seas in the Southern Ocean. They occur from 200 to 2,454 m.
Hepatus pudibundus, the flecked box crab, is a crab from the class Malacostraca. They are found in the Atlantic Ocean with Brazil having a dense population of H. pudibundus, as they are one of the most commonly seen crabs in the country. Many of the studies done on H. pudibubus have occurred in the Ubatuba region of Brazil, where there is a rapid expansion of tourism that is affecting marine ecosystems.
Lithodes turkayi is a species of king crab. It has been found at depths of 70–1,696 m (230–5,564 ft) and lives in the Pacific Ocean off the coast of Chile, the southern Atlantic Ocean near the Falkland Islands, and the Southern Ocean in the Bellingshausen Sea.
