King crab

King crabs, also called stone crabs, are a family of crab-like decapod crustaceans chiefly found in cold seas. Because of their large size and the taste of their flesh, many species are widely caught and sold as food, the most common being the red king crab (Paralithodes camtschaticus).

King crabs are generally believed to be derived from hermit crab ancestors, which may explain the asymmetry still found in the adult forms. Although some doubt still exists about this theory, king crabs are the most widely quoted example of carcinisation (shellification/crustification) among the Decapoda (familiar crustaceans). The evidence for this explanation comes from the asymmetry of the king crab's abdomen, which is thought to reflect the asymmetry of hermit crabs, which must fit into a spiral shell.

Species

Around 40 species are known , in 14 genera: Acantholithodes Holmes, 1895
Acantholithodes hispidus (Stimpson, 1860)
Cryptolithodes Brandt, 1848
Cryptolithodes brevifrons
Cryptolithodes sitchensis Brandt, 1853 — umbrella crab
Cryptolithodes typicus Brandt, 1848 — butterfly crab
Dermaturus Brandt, 1850
Dermaturus mandtii Brandt, 1850 — wrinkled crab
Glyptolithodes Faxon, 1895
Glyptolithodes cristatipes (Faxon, 1893)
Hapalogaster Brandt, 1850
Hapalogaster cavicauda Stimpson, 1859
Hapalogaster grebnitzkii Schalfeew, 1892
Hapalogaster mertensii Brandt, 1850
Lithodes Latreille, 1806
Lithodes aequispinus J. E. Benedict, 1895 — golden king crab
Lithodes agassizii
Lithodes antarcticus - Chilean centolla or Chilean king crab
Lithodes couesi J. E. Benedict, 1895 — scarlet king crab
Lithodes longispina Sakai, 1971
Lithodes maja (Linnaeus, 1758) — Norway king crab
Lithodes nintokuae Sakai, 1976
Lopholithodes Brandt, 1848
Lopholithodes foraminatus (Stimpson, 1859) — brown box crab
Lopholithodes mandtii Brandt, 1848 — Puget Sound king crab
Neolithodes A. Milne-Edwards & Bouvier, 1894
Neolithodes agassizii (S. I. Smith, 1882)
Neolithodes diomedeae (J. E. Benedict, 1895)
Neolithodes grimaldii (A. Milne-Edwards & Bouvier, 1894)
Oedignathus Benedict, 1895
Oedignathus inermis (Stimpson, 1860) — granular claw crab
Paralithodes Brandt, 1848
Paralithodes brevipes (H. Milne Edwards & Lucas, 1841)
Paralithodes californiensis (J. E. Benedict, 1895) — California king crab
Paralithodes camtschaticus (Tilesius, 1815) — red king crab
Paralithodes platypus Brandt, 1850 — blue king crab
Paralithodes rathbuni (J. E. Benedict, 1895)
Paralomis White, 1856
Paralomis bouvieri Hansen, 1908
Paralomis cubensis Chace, 1939
Paralomis haigae Eldredge, 1976
Paralomis longipes Faxon, 1893
Paralomis manningi A. B. Williams, C. R. Smith & Baco, 2000
Paralomis multispina (J. E. Benedict, 1895)
Paralomis pacifica Sakai, 1978
Paralomis seagranti Eldredge, 1976
Paralomis verrilli (J. E. Benedict, 1895)
Phyllolithodes Brandt, 1848
Phyllolithodes papillosus Brandt, 1848 — flatspine triangle crab, heart crab
Placetron Schalfeew, 1892
Placetron wosnessenskii Schalfeew, 1892 — scaled crab
Rhinolithodes Brandt, 1848
Rhinolithodes wosnessenskii Brandt, 1848 — rhinoceros crab

Glyptolithodes

Glyptolithodes is found chiefly in the Southern Hemisphere, but extending as far north as California, although all its closest relatives live in the Northern Hemisphere. Its single species, G. cristatipes was originally placed in the genus Rhinolithodes.

Lithodes

Lithodes aequispinus

The golden king crab, Lithodes aequispinus, is caught in the Aleutian Chain off the coast of Alaska. The golden king crab is significantly smaller than the red and blue king crabs, averaging 5–8 lb (2–4 kg). It tastes similar to the red and blue king crabs, though perhaps somewhat sweeter. They are considerably cheaper due to their appearance and size.

Significant populations occur in pockets in the waters off the Pribilof and Shumagin Islands, Shelikof Strait, Prince William Sound and at least as far south as lower Chatham Strait in the south-east, where a regular commercial fishery occurs annually.It should be noted they occur in deeper water than the red king crab, often in depths exceeding 300 fathoms (1800 feet). Juvenile golden king crabs are cryptic and rely on structure-forming sessile invertebrates growing on the sea floor, such as corals, sponges and sea-whips, to provide habitat. These sessile invertebrates are slow-growing and they are at risk in certain areas where commercial fishing by bottom trawling has been common practice. For this reason, large tracts of the sea floor along the Aleutian Island chain has been protected from bottom trawling under the Magnuson-Stevens Fishery Conservation and Management Act.

Lithodes couesi

The scarlet king crab, Lithodes couesi, is not often fished due to its small size and insufficient population to support commercial harvesting.

Lithodes maja

Lithodes maja occurs in the North Atlantic, including Northern Europe and Canada's east coast. It is not abundant enough to support commercial fishery, and is becoming rare in some areas.

Oedignathus

Oedignathus inermis, the only species in the genus Oedignathus, is found on the west coast of North America and separately around the coasts of Japan. Its claws and walking legs are covered in numerous tubercles rather than setae or spines, which distinguishes it from other genera.

Paralithodes

Paralithodes camtschaticus

The red king crab, Paralithodes camtschaticus, is a very large species, sometimes reaching a carapace width of 11 in (28 cm) and a leg span of 6 ft (1.83 m). Its natural range is the Bering Sea, between the Aleutian Islands and St. Lawrence Island. It can now also be found in the Barents Sea and the European Arctic, where it was intentionally introduced and is now becoming a pest.

Red Paralithodes camtschaticus and blue king crab Paralithodes platypus are some of the most important fisheries in Alaska, however populations have fluctuated in the past 25 years and some areas are currently closed due to overfishing. The two species are similar in size, shape and life history. Habitat is the main factor separating the range of blue and red king crabs in the Bering Sea. Red king crabs prefer shallow, muddy or sandy habitats in Bristol Bay and Norton Sound, while blue king crabs prefer the deeper areas comprised of cobble, gravel and rock that occur around the Pribilof, St. Matthew, St. Lawrence and the Diomede Islands.

Red king crabs have an 11 month brood cycle in their first reproductive year and a 12 month cycle thereafter. Both red and blue king crabs have planktotrophic larvae that undergo 4 zoeal stages in the water column and a non-feeding, glaucothoe stage which is an intermediate stage which seeks appropriate habitat on the sea floor.

Paralithodes platypus

The blue king crab, Paralithodes platypus, lives near St. Matthew Island and the Pribilof Islands, Alaska, and is the largest of all the king crabs, sometimes exceeding 18 lb (8 kg) in weight. The blue king crab is often sold as the coveted red king crab because it resembles and tastes similar to red king crab when cooked. Both the St. Matthew and Pribilof blue king crab stocks are classified as overfished and no longer support commercial fisheries.

Translation of "King crab"

Malay: Ketam raja, Danish: Troldkrabbe, German: Stein- und Königskrabben, Spanish: Lithodidae, French: Lithodidae, Norwegian (Nynorsk): Trollkrabbar.