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King crabs
Temporal range: Miocene–Recent
Spiny king crab md.jpg
Paralithodes californiensis
Scientific classification e
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Suborder: Pleocyemata
Infraorder: Anomura
Superfamily: Lithodoidea
Samouelle, 1819
Family: Lithodidae
Samouelle, 1819
Genera
  • Cryptolithodes
  • Glyptolithodes
  • Lithodes
  • Lopholithodes
  • Neolithodes
  • Paralithodes
  • Paralomis
  • Phyllolithodes
  • Rhinolithodes
  • Sculptolithodes
King crab in Kirkenes
King crab meat is considered a delicacy.

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

King crabs are generally thought to be derived from hermit crab-like 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 theory, king crabs are the most widely quoted example of carcinisation among the Decapoda. 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.

Controversial taxon

Although formerly classified among the hermit crabs in the superfamily Paguroidea, king crabs are now placed in a separate superfamily, Lithodoidea. This is not without controversy, as there is widespread consensus in the scientific community that king crabs are derived from hermit crabs and closely related to pagurid hermit crabs, and therefore a separate superfamily in the classification poorly reflects the phylogenetic relationship of this taxon.

Species

CSIRO ScienceImage 2839 Spiny Stone King Crab
Lithodes longispina

Around 121 species are known, in 10 genera:

  • Cryptolithodes Brandt, 1848
    • Cryptolithodes expansus Miers, 1879
    • Cryptolithodes sitchensis Brandt, 1853 – umbrella crab
    • Cryptolithodes typicus Brandt, 1848 – butterfly crab
  • Glyptolithodes Faxon, 1895
    • Glyptolithodes cristatipes (Faxon, 1893)
  • Lithodes Latreille, 1806
    • Lithodes aequispinus J. E. Benedict, 1895 – golden king crab
    • Lithodes aotearoa Ahyong, 2010
    • Lithodes australiensis Ahyong, 2010
    • Lithodes ceramensis Takeda & Nagai, 2004
    • Lithodes chaddertoni Ahyong, 2010
    • Lithodes confundens Macpherson, 1988
    • Lithodes couesi J. E. Benedict, 1895 – scarlet king crab
    • Lithodes ferox Filhol, 1885
    • Lithodes formosae Ahyong & Chan, 2010
    • Lithodes galapagensis Hall & Thatje, 2009
    • Lithodes jessica Ahyong, 2010
    • Lithodes longispina Sakai, 1971
    • Lithodes macquariae Ahyong, 2010
    • Lithodes maja (Linnaeus, 1758) – Norway king crab
    • Lithodes mamillifer Macpherson, 1988d
    • Lithodes mandtii
    • Lithodes manningi Macpherson, 1988
    • Lithodes megacantha Macpherson, 1991
    • Lithodes murrayi Henderson, 1888
    • Lithodes nintokuae Sakai, 1976
    • Lithodes panamensis Faxon, 1893
    • Lithodes paulayi Macpherson & Chan, 2008
    • Lithodes rachelae Ahyong, 2010
    • Lithodes richeri Macpherson, 1990
    • Lithodes robertsoni Ahyong, 2010
    • Lithodes santolla (Molina, 1782) – Chilean centolla or Chilean king crab
    • Lithodes turkayi Macpherson, 1988
    • Lithodes turritus Ortmann, 1892
    • Lithodes unicornis Macpherson, 1984
    • Lithodes wiracocha Haig, 1974
  • 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 asperrimus Barnard, 1947
    • Neolithodes brodiei Dawson & Yaldwyn, 1970
    • Neolithodes bronwynae Ahyong, 2010
    • Neolithodes capensis Stebbing, 1905
    • Neolithodes diomedeae (J. E. Benedict, 1895)
    • Neolithodes duhameli Macpherson, 2004
    • Neolithodes flindersi Ahyong, 2010
    • Neolithodes grimaldii (A. Milne-Edwards & Bouvier, 1894)
    • Neolithodes nipponensis Sakai, 1971
    • Neolithodes vinogradovi Macpherson, 1988
    • Neolithodes yaldwyni Ahyong & Dawson, 2006
  • 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 aculeata Henderson, 1888
    • Paralomis africana Macpherson, 1982
    • Paralomis alcockiana Hall & Thatje, 2009
    • Paralomis anamerae Macpherson, 1988
    • Paralomis arae Macpherson, 2001
    • Paralomis arethusa Macpherson, 1994
    • Paralomis aspera Faxon, 1893
    • Paralomis birsteini Macpherson, 1988
    • Paralomis bouvieri Hansen, 1908
    • Paralomis ceres Macpherson, 1989
    • Paralomis chilensis Andrade, 1980
    • Paralomis cristata Takeda & Ohta, 1979
    • Paralomis cristulata Macpherson, 1988
    • Paralomis cubensis Chace, 1939
    • Paralomis danida Takeda & Bussarawit, 2007
    • Paralomis dawsoni Macpherson, 2001
    • Paralomis debodeorum Feldmann, 1998
    • Paralomis diomedeae (Faxon, 1893)
    • Paralomis dofleini Balss, 1911
    • Paralomis echidna Ahyong, 2010
    • Paralomis elongata Spiridonov, Türkay, Arntz & Thatje, 2006
    • Paralomis erinacea Macpherson, 1988
    • Paralomis formosa Henderson, 1888
    • Paralomis gowlettholmes Ahyong, 2010
    • Paralomis granulosa (Hombron & Jacquinot, 1846)
    • Paralomis grossmani Macpherson, 1988
    • Paralomis haigae Eldredge, 1976
    • Paralomis hirtella de Saint Laurent & Macpherson, 1997
    • Paralomis histrix (De Haan, 1849)
    • Paralomis hystrixoides Sakai, 1980
    • Paralomis inca Haig, 1974
    • Paralomis indica Alcock & Anderson, 1899
    • Paralomis investigatoris Alcock & Anderson, 1899
    • Paralomis jamsteci Takeda & Hashimoto, 1990
    • Paralomis japonicus Balss, 1911
    • Paralomis kyushupalauensis Takeda, 1985
    • Paralomis longidactylus Birstein & Vinogradov, 1972
    • Paralomis longipes Faxon, 1893
    • Paralomis makarovi Hall & Thatje, 2009
    • Paralomis manningi Williams, Smith & Baco, 2000
    • Paralomis medipacifica Takeda, 1974
    • Paralomis mendagnai Macpherson, 2003
    • Paralomis microps Filhol, 1884
    • Paralomis multispina (Benedict, 1895)
    • Paralomis nivosa Hall & Thatje, 2009
    • Paralomis ochthodes Macpherson, 1988
    • Paralomis odawarai (Sakai, 1980)
    • Paralomis otsuae Wilson, 1990
    • Paralomis pacifica Sakai, 1978
    • Paralomis papillata (Benedict, 1895)
    • Paralomis pectinata Macpherson, 1988
    • Paralomis phrixa Macpherson, 1992
    • Paralomis poorei Ahyong, 2010
    • Paralomis roeleveldae Kensley, 1981
    • Paralomis seagranti Eldredge, 1976
    • Paralomis serrata Macpherson, 1988
    • Paralomis spectabilis Hansen, 1908
    • Paralomis spinosissima Birstein & Vinogradov, 1972
    • Paralomis staplesi Ahyong, 2010
    • Paralomis stella Macpherson, 1988
    • Paralomis stevensi Ahyong & Dawson, 2006
    • Paralomis taylorae Ahyong, 2010
    • Paralomis truncatispinosa Takeda & Miyake, 1980
    • Paralomis tuberipes Macpherson, 1988
    • Paralomis verrilli (Benedict, 1895)
    • Paralomis webberi Ahyong, 2010
    • Paralomis zealandica Dawson & Yaldwyn, 1971
  • Phyllolithodes Brandt, 1848
    • Phyllolithodes papillosus Brandt, 1848 – flatspine triangle crab, heart crab
  • Rhinolithodes Brandt, 1848
    • Rhinolithodes wosnessenskii Brandt, 1848 – rhinoceros crab
  • Sculptolithodes Makarov, 1934
    • Sculptolithodes derjugini Makarov, 1934

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.

Paralithodes

Red (P. camtschaticus) and blue (P. platypus) king crabs 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 made up of cobble, gravel and rock that occur around the Pribilof, St. Matthew, St. Lawrence, and 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 intermediate glaucothoe stage which seeks appropriate habitat on the sea floor.

The Childrens Museum of Indianapolis - Alaskan red king crab
Red king crabs make up over 90% of the annual king crab harvest. This crab is in the collection of the Children's Museum of Indianapolis.

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 (1.8 m). Its natural range is the Bering Sea around the Kamchatka Peninsula area, 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.

Paralithodes platypus

The blue king crab, Paralithodes platypus, lives near St. Matthew Island, the Pribilof Islands, and the Diomede Islands, Alaska, and there are populations along the coasts of Japan and Russia. Blue king crabs from the Pribilof Islands are the largest of all the king crabs, sometimes exceeding 18 lb (8 kg) in weight.

Symbiosis

Species of the king crab, including Neolithodes diomedeae, use a species (Scotoplanes Sp. A) of sea cucumber (often called as “sea pigs”) as hosts and can be found on top of and under Scotoplanes. The Scotoplanes reduce the risk of predation for the N. diomedeae, while the Scotoplanes are not harmed from being hosts, which supports the consensus that the two organisms have a commensal relationship.

See also

Kids robot.svg In Spanish: Lithodidae para niños

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