Majidae is a
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...
of
crab
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (abdomen) ( el, βραχύς , translit=brachys = short, / = tail), usually hidden entirely under the thorax. They live in all the ...
s, comprising around 200
marine species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...
inside 52 genera, with a
carapace
A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the under ...
that is longer than it is broad, and which forms a point at the front. The
legs
A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element c ...
can be very long in some species, leading to the name "
spider crab
The Majoidea are a superfamily of crabs which includes the various spider crabs.
Taxonomy
In "''A classification of living and fossil genera of decapod crustaceans''" De Grave and colleagues divided Majoidea into six families:
* Family Epial ...
". The
exoskeleton
An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton ( endoskeleton) in for example, a human. In usage, some of the ...
is covered with bristles to which the crab attaches
alga
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mi ...
e and other items to act as
camouflage
Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...
.
Genera
The roughly 200 extant and over 50 extinct species are divided among 52 genera in 5 subfamilies:
''
Eurynolambrinae''
Števčić, 1994
*''
Eurynolambrus''
H. Milne-Edwards & Lucas, 1841
''
Majinae''
Samouelle, 1819
*''
Ageitomaia''
Griffin & Tranter, 1986
*''
Anacinetops''
Miers, 1879
*''
Choniognathus''
Rathbun, 1932
*''
Cyclax''
Dana, 1851
*''
Entomonyx''
Miers, 1884
*''
Eurynome
Eurynomê (; Ancient Greek: Εὐρυνόμη, from , ''eurys'', "broad" and , ''nomos'', "pasture" or "law") is a name that refers to the following characters in Greek mythology:
* Eurynome, pre-Olympian queen and wife of Ophion
*Eurynome (Ocea ...
''
Leach, 1814
*''
Jacquinotia''
Rathbun, 1915
*''
Kasagia''
Richer de Forges & Ng, 2007
*''
Kimbla''
Griffin & Tranter, 1986
*''
Leptomithrax''
Miers, 1876
*''
Maiopsis''
Faxon, 1893
*''
Maja
Maja can refer to:
Places
* Maja, Croatia, a village
* Maja, Banten, a subdistrict in Lebak Regency, Banten, Indonesia
** Maja railway station
* Maja, West Java, a subdistrict in Majalengka Regency, West Java, Indonesia
* Maja River, a tribu ...
''
Lamarck, 1801
*''
Majella
The Maiella (or Majella) is a massif in the Central Apennines, in Abruzzo, central Italy.
Geography
The mountain is located at the boundary between the provinces of Chieti, Pescara and L'Aquila.
The highest peak is Monte Amaro at 2,793&n ...
''
Ortmann, 1893
*''
Microhalimus''
Haswell, 1880
*''
Naxia''
Latreille, 1825
*''
Notomithrax''
Griffin, 1963
*''
Paraentomonyx''
T. Sakai, 1983
*''
Paramithrax''
H. Milne-Edwards, 1837
*''
Pippacirama''
Griffin & Tranter, 1986
*''
Prismatopus''
Ward, 1933
*''
Schizophroida''
T. Sakai, 1933
*''
Schizophrys''
White, 1848
*''
Seiitaoides''
Griffin & Tranter, 1986
*''
Temnonotus''
A. Milne-Edwards, 1875
*''
Teratomaia''
Griffin & Tranter, 1986
*''
Thersandrus''
Rathbun, 1897
*''
Tumulosternum''
McCulloch, 1913
*''
Wilsonimaia'' †
Blow & Manning, 1996
''
Micromaiinae'' †
Beurlen, 1930
*''
Micromaia'' †
Bittner, 1875
*''
Mithracia'' †
Bell, 1858
*''
Pisomaja'' †
Lőrenthey, in Lőrenthey & Beurlen, 1929
''
Mithracinae''
MacLeay, 1838
*''
Ala''
Lockington, 1877
*''
Antarctomithrax'' †
Feldmann, 1994
*''
Coelocerus''
A. Milne-Edwards, 1875
*''
Cyclocoeloma''
Miers, 1880
*''
Cyphocarcinus''
A. Milne-Edwards, 1868
*''
Leptopisa''
Stimpson, 1871
*''
Macrocoeloma''
Miers, 1879
*''
Micippa''
Leach, 1817
*''
Microphrys''
Milne-Edwards, 1851
*''
Mithraculus''
White, 1847
*''
Mithrax''
A. G. Desmarest, 1823
*''
Nemausa''
A. Milne-Edwards, 1875
*''
Paranaxia''
Rathbun, 1924
*''
Picroceroides''
Miers, 1886
*''
Stenocionops''
A. G. Desmarest, 1823
*''
Teleophrys''
Stimpson, 1860
*''
Thoe''
Bell, 1836
*''
Tiarinia''
Dana, 1851
''
Planoterginae''
Števčić, 1991
*''
Hemus''
A. Milne-Edwards, 1875
*''
Planotergum''
Balss, 1935
Image:Majoidea (pe Cyclocoeloma tuberculata) Landaagiraavaru.JPG, '' Cyclocoeloma cf. tuberculata''
Image:Leptomithrax gaimardii P2023255.JPG, '' Leptomithrax gaimardii''
Image:Maja squinado.jpg, ''Maja squinado
''Maja squinado'' (the European spider crab, spiny spider crab or spinous spider crab) is a species of migratory crab found in the north-east Atlantic and the Mediterranean Sea. The appearance of the European spider crab is similar to the much l ...
''
Image:Micippa platipes, sur le dos.jpg, '' Micippa platipes'' (on its back)
Image:Female Mithraculus sculptus Crab.jpg, '' Mithraculus sculptus''
Image:Mithrax pilosus.jpg, '' Mithrax pilosus''
References
External links
*
*
Majoidea
Decapod families
Taxa named by George Samouelle
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