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Ophiuridae
Ophiuridae are a large family of brittle stars of the suborder Ophiurina. Description The arms are simple and unbranched, projecting from and well-fused to the edge of the disc. These arms move horizontally. The arm spines short and movable. They lie flat against the arms when stimulated, but held erect when the brittle star is at rest. Disc and arms are covered in naked, distinct scales. The scales are situated at both sides of the disc. The jaw is surrounded by a continuous series of mouth papillae. The base of the arm contains a single arm comb or an inner and outer arm comb. Systematics and phylogeny The fossils of Ophiuridae date back to Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferou ... ('' Aganaster''†). The family includes the following living genera: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brittle Star
Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomotion. The ophiuroids generally have five long, slender, whip-like arms which may reach up to in length on the largest specimens. The Ophiuroidea contain two large clades, Ophiurida (brittle stars) and Euryalida (basket stars). Over 2,000 species of brittle stars live today. More than 1,200 of these species are found in deep waters, greater than 200 m deep. Range The ophiuroids diverged in the Early Ordovician, about 500 million years ago. Ophiuroids can be found today in all of the major marine provinces, from the poles to the tropics. Basket stars are usually confined to the deeper parts of this range; Ophiuroids are known even from abyssal (>6,000 m) depths. However, brittle stars are also common members of reef communities, where t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiuroidea
Brittle stars, serpent stars, or ophiuroids (; ; referring to the serpent-like arms of the brittle star) are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their flexible arms for locomotion. The ophiuroids generally have five long, slender, whip-like arms which may reach up to in length on the largest specimens. The Ophiuroidea contain two large clades, Ophiurida (brittle stars) and Euryalida (basket stars). Over 2,000 species of brittle stars live today. More than 1,200 of these species are found in deep waters, greater than 200 m deep. Range The ophiuroids diverged in the Early Ordovician, about 500 million years ago. Ophiuroids can be found today in all of the major marine provinces, from the poles to the tropics. Basket stars are usually confined to the deeper parts of this range; Ophiuroids are known even from abyssal (>6,000 m) depths. However, brittle stars are also common members of reef communities, where th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiurina
Ophiurina are a suborder of brittle stars containing the majority of living brittle star species. Systematics There is currently no consensus as to the subdivision of the Ophiurina (traditionally, the infraorders have been treated as suborders). It contains the genera Amphiura, Amphipholis, and Ophiacantha. The suborder has been divided into the following recent infraorders and families :Smith, A.B.; Paterson, G.L.J., Ophiuroid phylogeny and higher taxonomy: morphological, molecular and palaeontological perspectives. Zool. J. Linn. Soc. 114 (1995) * Ophiacanthidae Hemieuryalina * Hemieuryalidae Chilophiurina * Ophiuridae Gnathophiurina * Amphilepididae * Amphiuridae * Ophiothricidae * Ophiactidae *Ophionereididae *Ophiocomidae Ophiocomidae are a family of brittle stars of the suborder Ophiurina. Systematics and phylogeny Ophiocomidae has been placed (along with Ophionereididae) to the superfamily Ophiocomidea and infraorder Order ( la, ordo) is one of the eigh ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiura Ophiura
''Ophiura ophiura'' or the serpent star is a species of brittle star in the order Ophiurida. It is typically found on coastal seabeds around northwestern Europe. Description ''Ophiura ophiura'' has a circular central disc up to 35 mm (1.5 in) wide and five radially arranged, narrow arms each up to long. The general colour is mottled reddish-brown with a paler underside. Both the top and the underside of the disc are covered with calcareous plates. The arms are joined to the top rather than the edge of the disc and further small, articulating plates allow the arms to bend from side to side. Small spines on the arms lie flat against the surface. Four larger plates occur across the root of each arm with the outer pair having a comb-like edge, with 20 to 30 fine papillae in each.''Ophiura ophiura'' (Linnae ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
