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Sternoptyx Diaphana
''Sternoptyx diaphana'', the diaphanous hatchetfish, is a species of deep sea ray-finned fish in the family Sternoptychidae. It is the type species of the genus ''Sternoptyx'', and was first described by the French naturalist Johann Hermann in ''Der Naturforscher'' 1781. Description ''Sternoptyx diaphana'' is a short, deep-bodied fish with a laterally compressed body and a maximum length of about . The mouth is nearly vertical, the snout is short and the eyes are large. The body slopes steeply up from the head and levels off at the caudal peduncle. In front of the dorsal fin is a toothed, pear-shaped translucent plate supported by a single spine. The dorsal fin has 9 to 12 soft rays and the anal fin 13 to 14. There is a translucent fold of skin just below the short tail, and another below the ventral region of the body. There are photophores behind and below the eye, on the gill cover, and rows of photophores on the underside of the fish. The dorsal region is dark, the flanks a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Hermann
Johann, or Jean-Frederic, Hermann, or Herrmann, (31 December 1738 in Barr, Alsace – 4 October 1800 in Strasbourg) was a French physician and naturalist. In 1769 he was appointed professor of medicine at the School of Public Health of Strasbourg, then, in 1778, professor of philosophy, before going on, in 1784, to succeed Jacob Reinbold Spielmann as chair of chemistry, natural history and materia medica. In 1794 he became professor of botany and materia medica in the new School of Medicine. He was the author of ''Tabula affinitatum animalium '' (1783) and ''Observationes zoologicae quibus novae complures'', published posthumously in 1804. His collections and library of 18,000 volumes formed the basis of the Natural History Museum of Strasbourg, where a reconstruction of his natural history cabinet was opened in 1988 . Hermann was also in charge of Strasbourg's botanical garden, where he was responsible for a large increase in the number of living plant species. The garden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diel Vertical Migration
Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The word ''diel'' comes from the Latin ''dies'' day, and means a 24-hour period. The migration occurs when organisms move up to the uppermost layer of the sea at night and return to the bottom of the daylight zone of the oceans or to the dense, bottom layer of lakes during the day. It is important to the functioning of deep-sea food webs and the biologically driven sequestration of carbon. In terms of biomass, it is the largest synchronous migration in the world. It is not restricted to any one taxon as examples are known from crustaceans (copepods), molluscs (squid), and ray-finned fishes (trout). The phenomenon may be advantageous for a number of reasons, most typically to access food and avoid predators. It is triggered by various stimuli, the most prominent being response to changes in light i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least-concern Species
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphipoda
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes the terrestrial sandhoppers such as ''Talitrus saltator''. Etymology and names The name ''Amphipoda'' comes, via New Latin ', from the Greek roots 'on both/all sides' and 'foot'. This contrasts with the related Isopoda, which have a single kind of thoracic leg. Particularly among anglers, amphipods are known as ''freshwater shrimp'', ''scuds'', or ''sideswimmers''. Description Anatomy The body of an amphipod is divided into 13 segments, which can be grouped into a head, a thorax and an abdomen. The head is fused to the thorax, and bears two pairs of antennae and one pair of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copepod
Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor), a number of species have parasitic phases, and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, and puddles, damp moss, or water-filled recesses (phytotelmata) of plants such as bromeliads and pitcher plants. Many live underground in marine and freshwater caves, sinkholes, or stream beds. Copepods are sometimes used as Ecological indicator, biodiversity indicators. As with other crustaceans, copepods have a larval form. For copepods, the egg hatches into a Crustacean larvae#Nauplius, nauplius form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decapoda
The Decapoda or decapods (literally "ten-footed") are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crabs, lobsters, crayfish, shrimp and prawns. Most decapods are scavengers. The order is estimated to contain nearly 15,000 species in around 2,700 genera, with around 3,300 fossil species. Nearly half of these species are crabs, with the shrimp (about 3,000 species) and Anomura including hermit crabs, porcelain crabs, squat lobsters (about 2500 species) making up the bulk of the remainder. The earliest fossil decapod is the Devonian ''Palaeopalaemon''. Anatomy Decapods can have as many as 38 appendages, arranged in one pair per body segment. As the name Decapoda (from the Greek , ', "ten", and , '' -pod'', "foot") implies, ten of these appendages are considered legs. They are the pereiopods, found on the last five thoracic segments. In many decapods, one pair of these "legs" has enlarged pincers, called chelae, with the legs be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krill
Krill are small crustaceans of the order Euphausiacea, and are found in all the world's oceans. The name "krill" comes from the Norwegian Norwegian, Norwayan, or Norsk may refer to: *Something of, from, or related to Norway, a country in northwestern Europe * Norwegians, both a nation and an ethnic group native to Norway * Demographics of Norway *The Norwegian language, including ... word ', meaning "small fry of fish", which is also often attributed to species of fish. Krill are considered an important trophic level connection – near the bottom of the food chain. They feed on phytoplankton and (to a lesser extent) zooplankton, yet also are the main source of food for many larger animals. In the Southern Ocean, one species, the Antarctic krill, ''Euphausia superba'', makes up an estimated biomass (ecology), biomass of around 379,000,000 tonnes, making it among the species with the largest total biomass. Over half of this biomass is eaten by whales, Pinniped, seals, pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photophore
A photophore is a glandular organ that appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors, however unlike an eye it is optimized to produce light, not absorb it. The bioluminescence can variously be produced from compounds during the digestion of prey, from specialized mitochondrial cells in the organism called photocytes ("light producing" cells), or, similarly, associated with symbiotic bacteria in the organism that are cultured. The character of photophores is important in the identification of deep sea fishes. Photophores on fish are used for attracting food or for camouflage from predators by counter-illumination. Photophores are found on some cephalopods including the firefly squid, which can create impressive light displays, as well as numerous other deep sea organisms such as the pocket shark Mollisquama mississippien ... [...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] |
Der Naturforscher
''Der Naturforscher'' ( "The Naturalist") was a German scientific publication of the Enlightenment devoted to natural history. It was published yearly from 1774 to 1804, by J. J. Gebauers Witwe and Joh. Jac. Gebauer at Halle and edited first by Johann Ernst Immanuel Walch (from 1774 to 1778) and later by Johann Christian Daniel von Schreber (from 1779 to 1802). Both editors were also contributors. Most of the articles concern aspects of invertebrate zoology, mostly entomology and conchology. A few concern ornithology and other subjects, including mineralogy. It is usually bound in fifteen volumes octavo. Indices and registers are given at ten year intervals enumerating 640 memoirs. Just over 150 plates accompany the text. Many of the illustrations are by Johann Stephan Capieux and are of a very high standard. Armin Geus provides comprehensive indices. Contributors Most authors contributing to ''Der Naturforscher'' were German, but the journal also included some French autho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sternoptyx
''Sternoptyx'' is an oceanic ray-finned fish genus which belongs in the family Sternoptychidae. This is the type genus of the Sternoptychidae, as well as the marine hatchetfish subfamily Sternoptychinae. ''Sternoptyx'' have silvery, high, and laterally compressed bodies and large, non-telescopic eyes. They are all relatively small, with even the largest species (''S. pseudobscura'' and ''S. pseudodiaphana'') not exceeding standard length. Species There are currently four recognized species in this genus: * '' Sternoptyx diaphana'' Hermann, 1781 (Diaphanous hatchetfish) * '' Sternoptyx obscura'' Garman, 1899 * '' Sternoptyx pseudobscura'' R. C. Baird, 1971 (Highlight hatchetfish) * '' Sternoptyx pseudodiaphana'' Borodulina, 1977 (False oblique hatchetfish) Fossils of this genus show that they have existed at least since the Early Oligocene, about 30 million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 terasec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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