Retroplumidae

	Retroplumidae Retroplumidae is a family of heterotrematan crabs, placed in their own (monotypic) superfamily, Retroplumoidea. Classification Eight genera are recognised, of which all but two are only known from fossils: '' Archaeopus'' † Rathbun, 1908 '' Bathypluma'' de Saint Laurent, 1989 '' Costacopluma'' † Collins & Morris, 1975 '' Cristipluma'' † Bishop, 1983a '' Loerentheya'' † Lőrenthey, in Lőrenthey & Beurlen, 1929 '' Loerenthopluma'' † Beschin, Busulini, De Angeli & Tessier, 1996 '' Retrocypoda'' † Vía, 1959 '' Retropluma'' Gill, 1894 Ten species in two genera survive in the deep sea of the Indo-Pacific region: '' Bathypluma chuni'' (Doflein, 1904) '' Bathypluma forficula'' De Saint Laurent, 1989 '' Bathypluma spinifer'' De Saint Laurent, 1989 '' Retropluma denticulata'' Rathbun, 1932 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Craverii ''Retropluma craverii'' is an extinct species of heterotrematan crabs belonging to the family Retroplumidae. The species name ''craverii'' honors the Italian explorer and naturalist Federico Craveri. Fossil record Fossils of ''Retropluma craverii'' are found in marine strata of the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Plumosa ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Denticulata ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Quadrata ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 ''Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Notopus ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Planiforma ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Serenei ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Solomonensis ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	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]
picture info	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]

	Retroplumidae Retroplumidae is a family of heterotrematan crabs, placed in their own (monotypic) superfamily, Retroplumoidea. Classification Eight genera are recognised, of which all but two are only known from fossils: '' Archaeopus'' † Rathbun, 1908 '' Bathypluma'' de Saint Laurent, 1989 '' Costacopluma'' † Collins & Morris, 1975 '' Cristipluma'' † Bishop, 1983a '' Loerentheya'' † Lőrenthey, in Lőrenthey & Beurlen, 1929 '' Loerenthopluma'' † Beschin, Busulini, De Angeli & Tessier, 1996 '' Retrocypoda'' † Vía, 1959 '' Retropluma'' Gill, 1894 Ten species in two genera survive in the deep sea of the Indo-Pacific region: '' Bathypluma chuni'' (Doflein, 1904) '' Bathypluma forficula'' De Saint Laurent, 1989 '' Bathypluma spinifer'' De Saint Laurent, 1989 '' Retropluma denticulata'' Rathbun, 1932 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Craverii ''Retropluma craverii'' is an extinct species of heterotrematan crabs belonging to the family Retroplumidae. The species name ''craverii'' honors the Italian explorer and naturalist Federico Craveri. Fossil record Fossils of ''Retropluma craverii'' are found in marine strata of the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Plumosa ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Denticulata ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Quadrata ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 ''Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 ''Retropluma notopus'' (Alcock & Anderson, 1894) ''Retropluma planiforma'' Kensley, 1969 ''Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 ''Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Notopus ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Planiforma ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Serenei ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †''Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 ''Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Retropluma Solomonensis ''Retropluma'' is a genus of heterotrematan crabs belonging to the family Retroplumidae. The extant species survive in the deep sea of the Indo-Pacific region. Species Species within this genus include: * †'' Retropluma borealis'' Fraaife et al. 2005 * †'' Retropluma craverii'' Crema 1895 '' Retropluma denticulata'' Rathbun, 1932 †'' Retropluma eocenica'' Via Boada 1959 * †'' Retropluma gallica'' Artal et al. 2006 * †'' Retropluma laurentae'' Collins et al. 2003 '' Retropluma notopus'' (Alcock & Anderson, 1894) '' Retropluma planiforma'' Kensley, 1969 '' Retropluma plumosa'' Tesch, 1918 '' Retropluma quadrata'' De Saint Laurent, 1989 '' Retropluma serenei'' De Saint Laurent, 1989 '' Retropluma solomonensis'' McLay, 2006 Fossil record Fossils of ''Retropluma'' are found in marine strata from the Neogene to the Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	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]
picture info	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]