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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 ... [...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] |
Species
In biology, a species is the basic unit of 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 the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Cucumber
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 sometim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Holothur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squirrel
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and to the dormice. Etymology The word ''squirrel'', first attested in 1327, comes from the Anglo-Norman which is from the Old French , the reflex of a Latin word , which was taken from the Ancient Greek word (; from ) 'shadow-tailed', referring to the long bushy tail which many of its members have. The native Old English word for the squirrel, , survived only into Middle English (as ) before being replaced. The Old English word is of Common Germanic origin, cognat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gummy Bear
Gummy bears (German: ''Gummibär'') are small, fruit gum candies, similar to a jelly baby in some English-speaking countries. The candy is roughly long and shaped in the form of a bear. The gummy bear is one of many gummies, popular gelatin-based candies sold in a variety of shapes and colors. History The gummy bear originated in Germany, where it is popular under the name (gum or gummy bear), or in the endearing form ( ittlegum or gummy bear). Gum arabic was the original base ingredient used to produce the gummy bears, hence the name ''gum'' or ''gummy''. Hans Riegel Sr., a confectioner from Bonn, started the Haribo company in 1920. In 1922, inspired by the trained bears seen at street festivities and markets in Europe through to the 19th century, he invented the Dancing Bear (''Tanzbär''), a small, affordable, fruit-flavored gum candy treat for children and adults alike, which was much larger in form than its later successor, the Gold-Bear (''Goldbär''). Even during ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tube Feet
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 contain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmopolitan Distribution
In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The extreme opposite of a cosmopolitan species is an endemic one, being found only in a single geographical location. Qualification The caveat “in appropriate habitat” is used to qualify the term "cosmopolitan distribution", excluding in most instances polar regions, extreme altitudes, oceans, deserts, or small, isolated islands. For example, the housefly is highly cosmopolitan, yet is neither oceanic nor polar in its distribution. Related terms and concepts The term pandemism also is in use, but not all authors are consistent in the sense in which they use the term; some speak of pandemism mainly in referring to diseases and pandemics, and some as a term intermediate between endemism and cosmopolitanism, in effect regarding pandemism as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
