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Psychropotidae
Psychropotidae is a family of deep-sea swimming sea cucumbers. The geographic range of some psychropotids is very extensive at abyssal depths, whereas other species are found within more restricted ranges.P. A. Tyler & D. S. M. Billett (1988) The Reproductive Ecology of Elasipodid Holothurians from the N. E. Atlantic, Biological Oceanography, 5:4, 273-296, DOI: 10.1080/01965581.1987.10749518 Description "Psychropotidae are elongate in shape, with the anterior part of the dorsal surface depressed. Many psychropotids have a large posterior appendage. They usually have 10-20 tentacles and ventrolateral radii, each with a single row of many small tube feet." Like all holothurians, psychropotids have calcareous deposits, vestigial elements of the usual Echinoderm skeleton. "In psychropotids, These are essentially similar to other Holothuroidea, differing in a very low degree of calcification", instead consisting mainly of connective tissue. The calcareous ring and spicules of Holothuro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benthodytes
''Benthodytes'' is a genus of sea cucumbers in the family Psychropotidae. Discovery This group of sea cucumbers was first described by scientists aboard the H.M.S. Challenger during its 1873-1876 voyage.Théel, H. (1882). Report on the Holothuroidea dredged by H.M.S. 'Challenger' during the years 1873-76. Part i. Report on the Scientific Results of the Voyage of H.M.S. Challenger during the years 1873–1876. Zoology. 4 (part 13): i-ix, 1-176, pl. 1-46., available online at http://19thcenturyscience.org/HMSC/HMSC-Reports/Zool-13/htm/doc.htm Théel described the genus: "Body more or less depressed, with the anterior part of its brim rather large. Mouth ventral, at a greater distance from the foremost extremity of the body. Anus posterior, dorsal, usually almost terminal. Tentacles (?) twelve to twenty. Pedicels arranged in a single row round the brim of the body and in a double one along the odd ambulacrum. The dorsal surface seldom naked, commonly with a greater or smaller number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psycheotrephes
''Psycheotrephes'' is a genus of sea cucumbers in the family Psychropotidae. Species The following species are recognised in the genus ''Psycheotrephes'': * '' Psycheotrephes discoveryi'' Rogacheva & Cross in Rogacheva et al., 2009 * '' Psycheotrephes exigua'' Théel, 1882 * '' Psycheotrephes magna'' Hansen, 1975 * '' Psycheotrephes recta'' (Vaney, 1908) References Holothuroidea genera Psychropotidae Taxa named by Johan Hjalmar Théel {{Holothuroidea-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychropotes
''Psychropotes'' is a genus of sea cucumbers in the family Psychropotidae. The members of this genus possess the ability to swim, although this is only facultative. Description As adults, species of ''Psychropotes'' are roughly cylindrical in shape and red to violet in colour. They have a sail-like appendage which can be used for swimming during the larval stage, but is no longer needed when it is fully grown. Larvae of ''Psychropotes'' species are benthopelagic and swim around using the aforementioned appendage, however researchers are still trying to understand its use when the holothurian is fully grown. Larvae are transparent and can grow to around 2 cm long. Species The following species are recognised in the genus ''Psychropotes'': * ''Psychropotes belyaevi'' Hansen, 1975 * '' Psychropotes depressa'' (Théel, 1882) * ''Psychropotes dubiosa'' Ludwig, 1893 * '' Psychropotes dyscrita'' (Clark, 1920) * '' Psychropotes fuscopurpurea'' Théel, 1882 * '' Psychropotes hyalin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychropotes Longicauda
''Psychropotes longicauda'' is a species of sea cucumber in the family Psychropotidae. It inhabits the deep sea where the adult is found on the seabed. The larva is pelagic and has an appendage shaped like a sail on its back which may enable it to move through the water. The animal is sometimes called the "gummy squirrel" because it looks like a squirrel-shaped gummy bear. Description As an adult, ''Psychropotes longicauda'' has eighteen short feeding tentacles, each with a leathery terminal disc with retractile processes projecting around the margin. Its body is very flexible and can grow to a length of between . It is approximately cylindrical but broadest and somewhat flattened near the anterior end. At the posterior end there is a dorsal, tail-like appendage up to long, either pointed or with a pair of unequal-length tips. There is a double row of small tube feet along the ventral surface and a single row of larger tube feet on each side of the body. The skin is soft and p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasipodida
Elasipodida is an order of sea cucumbers. They have numerous appendages, including conical papillae and leaf-like tentacles. Although many species are benthic, a number are pelagic, and may have their appendages modified to form sails or fins. Most members of the order inhabit deep-sea environments, such as the species of the genus '' Enypniastes''. Classification The following families are recognised in the order Elasipodida: * family Elpidiidae Théel, 1882 * family Laetmogonidae Ekman, 1926 * family † Palaeolaetmogonidae Reich, 2012 * family Pelagothuriidae Ludwig, 1893 * family Psychropotidae Théel, 1882 Image:Pelagothuria natatrix.jpg, The only true pelagic echinoderm known to date : ''Pelagothuria natatrix'' (here close to the Galapagos). Image:Expl0790 - Flickr - NOAA Photo Library.jpg, '' Benthodytes sp.'' Image:Scotoplanes globosa and crab.jpg, ''Scotoplanes globosa'' (a.k.a. "sea pig", family Elpidiidae) Image:Expl5475.jpg, A Pelagothuriidae Image:Expl5494.jpg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holothuroidea
Sea cucumbers are echinoderms from the class Holothuroidea (). They are marine animals with a leathery skin and an elongated body containing a single, branched gonad. Sea cucumbers are found on the sea floor worldwide. The number of holothurian () species worldwide is about 1,717, with the greatest number being in the Asia-Pacific region. Many of these are gathered for human consumption and some species are cultivated in aquaculture systems. The harvested product is variously referred to as '' trepang'', ''namako'', ''bêche-de-mer'', or ''balate''. Sea cucumbers serve a useful role in the marine ecosystem as they help recycle nutrients, breaking down detritus and other organic matter, after which bacteria can continue the decomposition process. Like all echinoderms, sea cucumbers have an endoskeleton just below the skin, calcified structures that are usually reduced to isolated microscopic ossicles (or sclerietes) joined by connective tissue. In some species these can sometimes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johan Hjalmar Théel
Johan Hjalmar Théel (14 June 1848 – 20 July 1937) was a Swedish zoologist and university professor. Early life Théel was born on 14 June 1848 in Säter, Sweden. He used to go on hunting trips along the coast of Norway in his youth and became fascinated by the plants and animals he encountered, especially the marine life. He met the zoologist Sven Ludvig Lovén who sparked his interest in sipunculid or peanut worms, especially the genus '' Phascolion''. He studied at Uppsala University and ''Phascolion'' was the subject for his thesis, written in 1875. He was also an artist and included his own illustrations in his published articles. In 1875, he accompanied the explorer Adolf Erik Nordenskiöld to the mouth of the Yenisei River in an attempt to find the Northeast Passage. He joined him on a similar voyage the following year and discovered a sea cucumber new to science, which he named ''Elpidia glacialis''. He was inducted into the Royal Swedish Academy of Sciences in 1884. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tube Foot
Tube feet (technically podia) are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on brittle stars, and have only a feeding function in feather stars. They are part of the water vascular system. Structure and function Tube feet function in locomotion, feeding, and respiration. The tube feet in a starfish are arranged in grooves along the arms. They operate through hydraulic pressure. They are used to pass food to the oral mouth at the center, and can attach to surfaces. A starfish that is inverted turns one arm over and attaches it to a solid surface, and levers itself the right way up. Tube feet allow these different types of animals to stick to the ocean floor and move slowly. Each tube foot consists of two parts: the ampulla and the podium. The ampulla is a water-filled sac contained in the body of the animal that contai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinoderm
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or "stone lilies". Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7,000 living species, making it the second-largest grouping of deuterostomes, after the chordates. Echinoderms are the largest entirely marine phylum. The first definitive echinoderms appeared near the start of the Cambrian. The echinoderms are important both ecologically and geologically. Ecologically, there are few other groupings so abundant in the biotic desert of the deep sea, as well as shallower oceans. Most echinoderms are able to reproduce asexually and regenerate tissue, organs, and limbs; in some cases, they can undergo complete regeneration from a single limb. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
