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Heterotremata
Heterotremata is a clade of crabs, comprising those crabs in which the genital openings are on the sternum in females, but on the legs in males. It comprises 68 families in 28 superfamilies. Evolution Heterotremata is the sister group to Thoracotremata within the clade Eubrachyura, having diverged during the Cretaceous period. Eubrachyura itself is a subset of the larger clade Brachyura, which consists of all "true crabs". A summary of the high-level internal relationships within Brachyura can be shown in the cladogram below: The internal relationships within Heterotremata are less certain, with many of the superfamilies found to be invalid. The proposed cladogram below is from analysis by Tsang ''et al'', 2014: Superfamilies * Aethroidea * Bellioidea * Bythograeoidea *Calappoidea *Cancroidea * Carpilioidea * Cheiragonoidea * Corystoidea * Dairoidea * Dorippoidea * Eriphioidea * Gecarcinucoidea * Goneplacoidea * Hexapodoidea * Leucosioidea *Majoidea * Orithyioidea * Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers. They first appeared during the Jurassic Period. Description Crabs are generally covered with a thick exoskeleton, composed primarily of highly mineralized chitin, and armed with a pair of chelae (claws). Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span up to . Several other groups of crustaceans with similar appearances – such as king crabs and porcelain crabs – are not true crabs, but have evolved features similar to true crabs through a process known as carcinisation. Environment Crabs are found in all of the world's oceans, as well as in fresh w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eubrachyura
Eubrachyura is a group of decapod crustaceans (ranked as a "section") comprising the more derived crabs. It is divided into two subsections, based on the position of the genital openings in the two sexes. In the Heterotremata, the openings are on the legs in the males, but on the sternum in females, while in the Thoracotremata, the openings are on the sternum in both sexes. This contrasts with the situation in other decapods, in which the genital openings are always on the legs. Heterotremata is the larger of the two groups, containing the species-rich superfamilies Xanthoidea and Pilumnoidea and all the freshwater crabs ( Gecarcinucoidea, Potamoidea). The eubrachyura is well known for actively and constantly building its own burrows. The fossil record of the Eubrachyura extends back to the Cretaceous; the supposed Bathonian (Middle Jurassic) representative of the group, '' Hebertides jurassica'', ultimately turned out to be Cenozoic in age. Here is a cladogram showing Eubra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoracotremata
Thoracotremata is a clade of crabs, comprising those crabs in which the genital openings in both sexes are on the sternum, rather than on the legs. It comprises 17 families in four superfamilies . Evolution Thoracotremata is the sister group to Heterotremata within the clade Eubrachyura, having diverged during the Cretaceous period. Eubrachyura itself is a subset of the larger clade Brachyura, which consists of all "true crabs". A summary of the high-level internal relationships within Brachyura can be shown in the cladogram below: The internal relationships within Thoracotremata are less certain, with many of the superfamilies found to be invalid. The proposed cladogram below is from analysis by Tsang ''et al'', 2014: Superfamilies and families *Ocypodoidea ** Camptandriidae **Dotillidae ** Heloeciidae ** Macrophthalmidae **Mictyridae **Ocypodidae ** Ucididae ** Xenophthalmidae * Pinnotheroidea **Pinnotheridae * Cryptochiroidea ** Cryptochiridae *Grapsoidea **G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromiacea
Dromiacea is a group of crabs, ranked as a section. It contains 240 extant and nearly 300 extinct species. Dromiacea is the most basal grouping of Brachyura crabs, diverging the earliest in the evolutionary history, around the Late Triassic or Early Jurassic. Below is a cladogram showing Dromiacea's placement within Brachyura: The larvae of Dromiacea resemble those of the Anomura more closely than those of other crabs. This may simply reflect their basal position in the crab phylogeny. The superfamily Eocarcinoidea, containing '' Eocarcinus'' and '' Platykotta'', was previously considered to be a member of the Dromiacea, but has since been transferred to the Anomura. The fossil record of Dromiacea reaches back at least as far as the Jurassic, and, if '' Imocaris'' is indeed a member, into the Carboniferous. Dromiacea primarily consists of two groups of superfamilies - Dromioidea and Homoloidea. See the below cladogram: Recent studies have found that some of the fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclodorippoida
Cyclodorippoida is a group of crabs, ranked as a section. It contains the single superfamily Cyclodorippoidea, which holds three families, Cyclodorippidae, Cymonomidae and Phyllotymolinidae. Below is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... showing Cyclodorippoida's placement within Brachyura: References Crabs {{Crab-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orithyiidae
''Orithyia sinica'', sometimes called tiger crab or the tiger face crab, is a "singularly unusual" species of crab, whose characteristics warrant its separation into a separate genus, family and even superfamily, having previously been included in the Dorippoidea or Leucosioidea. Its larvae, for instance, are unlike those of any other crab. Description ''O. sinica'' is a distinctive species, with stripes on the legs, and prominent eyespots on the carapace; the females' abdomen is unusually narrow, leaving the vulvae exposed. The legs are flattened at the end, and this is an adaptation to digging, not swimming. Distribution and fishery ''O. sinica'' is found along the coast of mainland Asia from South Korea to Hong Kong, but is missing from the nearby islands, such as Taiwan, the Ryukyu Islands and Japan, even though the intervening waters are shallow and the crab's larvae are planktonic. Throughout its range, ''O. sinica'' is fished on a small scale and commands high prices. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raninoida
Raninoida is a taxonomic section of the crabs, containing a single superfamily, Raninoidea. This group of crabs is unlike most, with the abdomen not being folded under the thorax. It comprises 46 extant species, and nearly 200 species known only from fossils. Below is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... showing Raninoidea's placement within Brachyura: References Crabs Taxa named by Wilhem de Haan {{Crab-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superfamily (taxonomy)
Superfamily may refer to: *Protein superfamily ** Superfamily database * Superfamily (taxonomy), a taxonomic rank * Superfamily (linguistics), also known as macrofamily * Font superfamily, a large typographic family * Superfamily (band) Superfamily was a Norwegian pop rock band from Moss, Norway. The band is composed of Steven Ray Wilson (lead vocals), Kim Granholt (keytar, synthesizer), Martin Steffensen (guitar), and Richard Lorentz (drums). Anders Nielsen, Terje Krumins and H ..., a Norwegian pop band * "Super Family", a group of comic characters {{Disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamoidea
Potamoidea is a superfamily of freshwater crabs, comprising the two families Potamidae Potamidae is a family (biology), family of freshwater crabs. It includes more than 650 species and nearly 100 genera, which are placed into two subfamilies: Potaminae and Potamiscinae. Subfamily Potaminae The Potaminae Ortmann, 1896 are distrib ... and Potamonautidae. Two previously recognised families, Deckeniidae and Platythelphusidae, are now treated as parts of the family Potamonautidae. References Crabs Arthropod superfamilies {{crab-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamonautidae
Potamonautidae is a family of freshwater crabs endemic to Africa, including the islands of Madagascar, the Seychelles, Zanzibar, Mafia, Pemba, Bioko, São Tomé, Príncipe and Sherbro Island. It comprises 18 extant genera and 138 extant species. Fossil remains dating from the Late Miocene period have been attributed to the family Potamonautidae. It comprises the following subfamilies and genera: ; Deckeniinae Ortmann, 1897 *'' Deckenia'' Hilgendorf, 1869 *'' Seychellum'' Ng, Števčić & Pretzmann, 1995 ; Hydrothelphusinae Bott, 1955 *'' Afrithelphusa'' Bott, 1969 *'' Boreas'' Cumberlidge & von Sternberg, 2002 *'' Globonautes'' Bott, 1959 *'' Hydrothelphusa'' A. Milne-Edwards, 1872 *'' Louisea'' Cumberlidge, 1994 *'' Madagapotamon'' Bott, 1965 *'' Malagasya'' Cumberlidge & von Sternberg, 2002 *''Marojejy'' Cumberlidge, Boyko & Harvey, 2002 *'' Skelosophusa'' Ng & Takeda, 1994 ; Potamonautinae Bott, 1970 *'' Erimetopus'' Rathbun, 1894 *''Foza'' Dai & Bo, 1994 *'' Liberonautes'' Bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potamidae
Potamidae is a family (biology), family of freshwater crabs. It includes more than 650 species and nearly 100 genera, which are placed into two subfamilies: Potaminae and Potamiscinae. Subfamily Potaminae The Potaminae Ortmann, 1896 are distributed around the Mediterranean Sea, on Socotra and eastwards to Northern India. *''Acanthopotamon'' Kemp, 1918 *''Alcomon'' Yeo & Ng, 2007 *''Himalayapotamon'' Pretzmann, 1966 *''Lobothelphusa'' Bouvier, 1917 *''Paratelphusula'' Alcock, 1909 *''Potamon'' Savigny, 1816 *''Socotra pseudocardisoma, Socotra'' Cumberlidge & Wranik, 2002 *''Socotrapotamon'' Apel & Brandis, 2000 Subfamily Potamiscinae The Potamiscinae Bott, 1970 are found in East Asia and Southeast Asia. *''Acartiapotamon'' Dai, 1999 *''Allopotamon'' Ng, 1988 *''Amamiku'' Naruse, Segawa & Shokita, 2004 *''Aparapotamon'' Dai & G. X. Chen, 1985 *''Apotamonautes'' Dai & Xing, 1993 *''Artopotamon'' Dai & G. X. Chen, 1985 *''Arquatopotamon'' Chu, Zhou & Sun, 2017 *''Aspermon'' Yeo & N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xantho Poressa
''Xantho poressa'', the jaguar round crab, is a species of crab from the eastern Atlantic Ocean. It is one of four species in the genus ''Xantho''. Description The juveniles of ''X. poressa'' are cryptically coloured as camouflage among the epibionts on the leaves of ''Posidonia'' with a variable carapace colour, which can be yellowish, reddish, brown, or dark grey with patches of another colour, usually white. The pereiopods are usually banded with dark brown or black bands alternating with white or translucent stripes or spots, although the fifth pereiopod is brighter and often unmarked. The adults are uniformly dark grey in colour and they leave the seagrass beds for more open, rocky substrates. Distribution ''X. poressa'' is distributed throughout the Black Sea and the Mediterranean Sea and into the warmer parts of the north eastern Atlantic to the Canary Islands. Biology The larvae of ''X. poressa'' go through four zoeal and one megalopal stages, which are typical of most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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