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Cottoperca Trigloides
''Cottoperca'' is a genus of marine ray-finned fishes belonging to the family Bovichtidae, the temperate icefishes or thornfishes. They are found in the southeastern Pacific, southwestern Atlantic and northern Southern Oceans off southern South America. Taxonomy ''Cottoperca'' was first formally described as a genus in 1875 by the Austrian ichthyologist Franz Steindachner with ''Cottoperca rosenbergii'' which Steindachner described as its only species. ''C. rosenbergii w''as later found to be a synonym of ''Batrachus trigloides'' which had been described by the German naturalist Johann Reinhold Forster in 1801. Some taxonomic authorities consider that ''Cottoperca'' is monotypic and that the only valid species is ''C. gobio'', while others state the only valid species is ''C. trigloides'', although this is not the position taken by the 5th edition of Fishes of the World, World Register of Marine Species, FishBase or the Catalog of Fishes, which all give the genus 2 species. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Franz Steindachner
Franz Steindachner (11 November 1834 in Vienna – 10 December 1919 in Vienna) was an Austrian Zoology, zoologist, ichthyologist, and herpetologist. He published over 200 papers on fishes and over 50 papers on reptiles and amphibians. Steindachner described hundreds of new species of fish and dozens of new amphibians and reptiles. At least seven species of reptile have been named after him. Work and career Being interested in natural history, Steindachner took up the study of fossil fishes on the recommendation of his friend Eduard Suess (1831–1914). In 1860 he was appointed to the position of director of the fish collection at the Naturhistorisches Museum, a position which had remained vacant since the death of Johann Jakob Heckel (1790–1857). (in German). Steindachner's reputation as an Ichthyology, ichthyologist grew, and in 1868 he was invited by Louis Agassiz (1807–1873) to accept a position at the Museum of Comparative Zoology at Harvard University. Steindachner took ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cottoperca Gobio
''Cottoperca'' is a genus of marine ray-finned fishes belonging to the family Bovichtidae, the temperate icefishes or thornfishes. They are found in the southeastern Pacific, southwestern Atlantic and northern Southern Oceans off southern South America. Taxonomy ''Cottoperca'' was first formally described as a genus in 1875 by the Austrian ichthyologist Franz Steindachner with ''Cottoperca rosenbergii'' which Steindachner described as its only species. ''C. rosenbergii w''as later found to be a synonym of ''Batrachus trigloides'' which had been described by the German naturalist Johann Reinhold Forster in 1801. Some taxonomic authorities consider that ''Cottoperca'' is monotypic and that the only valid species is ''C. gobio'', while others state the only valid species is ''C. trigloides'', although this is not the position taken by the 5th edition of Fishes of the World, World Register of Marine Species, FishBase or the Catalog of Fishes, which all give the genus 2 species. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least Concern
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] |
Bycatch
Bycatch (or by-catch), in the fishing industry, is a fish or other marine species that is caught unintentionally while fishing for specific species or sizes of wildlife. Bycatch is either the wrong species, the wrong sex, or is undersized or juveniles of the target species. The term "bycatch" is also sometimes used for untargeted catch in other forms of animal harvesting or collecting. Non- marine species (freshwater fish not saltwater fish) that are caught (either intentionally or unintentionally) but regarded as generally "undesirable" are referred to as "rough fish" (mainly US) and " coarse fish" (mainly UK). In 1997, the Organisation for Economic Co-operation and Development (OECD) defined bycatch as "total fishing mortality, excluding that accounted directly by the retained catch of target species". Bycatch contributes to fishery decline and is a mechanism of overfishing for unintentional catch. The average annual bycatch rate of pinnipeds and cetaceans in the US from 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sprattus Fuegensis
The Fueguian sprat or Falkland sprat (''Sprattus fuegensis'') is a herring-like, marine fish in the family Clupeidae found in the subtropical southwest Atlantic Ocean from 40° S to Tierra del Fuego and the Falkland Islands. Its depth range is from the surface to 10 m, and its length is up to 18 cm. The Fueguian sprat has a lower jaw slightly projecting, and a gill cover without bony radiating striae. The last two anal fin rays are not enlarged, and there are no dark spots on the flanks. The pterotic bulla is absent. It is a schooling species found in coastal waters, and a food item of hakes, sea birds and seals in Patagonian Falkland waters. Coloration is dark blue dorsally Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ... and silvery white laterally and ventrally, and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelp Forest
Kelp forests are underwater areas with a high density of kelp, which covers a large part of the world's coastlines. Smaller areas of anchored kelp are called kelp beds. They are recognized as one of the most productive and dynamic ecosystems on Earth.Mann, K.H. 1973. Seaweeds: their productivity and strategy for growth. Science 182: 975-981. Although algal kelp forest combined with coral reefs only cover 0.1% of Earth's total surface, they account for 0.9% of global Primary production, primary productivity. Kelp forests occur worldwide throughout temperate and polar region, polar coastal oceans. In 2007, kelp forests were also discovered in tropical waters near Ecuador.Graham, M.H., B.P. Kinlan, L.D. Druehl, L.E. Garske, and S. Banks. 2007. Deep-water kelp refugia as potential hotspots of tropical marine diversity and productivity. Proceedings of the National Academy of Sciences 104: 16576-16580. Physically formed by brown macroalgae, kelp forests provide a unique habitat for m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holdfast (biology)
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate. Holdfasts vary in shape and form depending on both the species and the substrate type. The holdfasts of organisms that live in muddy substrates often have complex tangles of root-like growths. These projections are called haptera and similar structures of the same name are found on lichens. The holdfasts of organisms that live in sandy substrates are bulb-like and very flexible, such as those of sea pens, thus permitting the organism to pull the entire body into the substrate when the holdfast is contracted. The holdfasts of organisms that live on smooth surfaces (such as the surface of a boulder) have flattened bases which adhere to the surface. The organism derives no nutrition from this intimate contact with the substrate, as the process of liberating nutrients from the substrate requires ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patagonian Shelf
The Argentine (sometimes referred to as Patagonian) Shelf is part of the South American continental shelf belonging to the Argentine Sea on the Atlantic seaboard, south of about 35°S. It adjoins the coasts of Uruguay, Argentina and the Falkland (Malvinas) Islands. Various authorities quote different dimensions of the shelf, depending on how they define its limits. Quoted statistics cites its area as being from 1.2 to 2.7 million square kilometres and its maximum width as being between 760 and 850 kilometres. The shelf itself can be divided into a 100 km band where the seabed slopes at about then a wide plain (250 to 450 km wide) where the seabed slopes gently to 200 m isobath. Apart from the Falklands Plateau (which lies to the east of the Falkland (Malvinas) Islands), the seabed then falls by up to to 2000 m and more. The Falklands Trough separates the Patagonian Shelf from the Scotia Arc The Scotia Arc is the island arc system forming the north, eas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Horn
Cape Horn ( es, Cabo de Hornos, ) is the southernmost headland of the Tierra del Fuego archipelago of southern Chile, and is located on the small Hornos Island. Although not the most southerly point of South America (which are the Diego Ramírez Islands), Cape Horn marks the northern boundary of the Drake Passage and marks where the Atlantic and Pacific Oceans meet. Cape Horn was identified by mariners and first rounded in 1616 by the Dutchman Willem Schouten and Jacob Le Maire, who named it after the city of Hoorn in the Netherlands. For decades, Cape Horn was a major milestone on the clipper route, by which sailing ships carried trade around the world. The waters around Cape Horn are particularly hazardous, owing to strong winds, large waves, strong currents and icebergs. The need for boats and ships to round Cape Horn was greatly reduced by the opening of the Panama Canal in August 1914. Sailing around Cape Horn is still widely regarded as one of the major challenges in y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelvic Fin
Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two endochondrally-derived bony girdles attached to bony radials. Dermal fin rays (lepidotrichia) are positioned distally from the radials. There are three pairs of muscles each on the dorsal and ventral side of the pelvic fin girdle that abduct and adduct the fin from the body. Pelvic fin structures can be extremely specialized in actinopterygians. Gobiids and lumpsuckers modify their pelvic fins into a sucker disk that allow them to adhere to the substrate or climb structures, such as waterfalls. In priapiumfish, males have modified their pelvic structures into a spiny copulatory device that grasps the female during mating. File:Pelvic fin skeleton.png, Pelvic fin skeleton for ''Danio rerio'', zebrafish. File:Zuignap waarmee de zwartbekgrond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (fish)
The operculum is a series of bones found in bony fish and chimaeras that serves as a facial support structure and a protective covering for the gills; it is also used for respiration and feeding. Anatomy The opercular series contains four bone segments known as the preoperculum, suboperculum, interoperculum and operculum. The preoperculum is a crescent-shaped structure that has a series of ridges directed posterodorsally to the organisms canal pores. The preoperculum can be located through an exposed condyle that is present immediately under its ventral margin; it also borders the operculum, suboperculum, and interoperculum posteriorly. The suboperculum is rectangular in shape in most bony fishy and is located ventral to the preoperculum and operculum components. It is the thinnest bone segment out of the opercular series and is located directly above the gills. The interoperculum is triangular shaped and borders the suboperculum posterodorsally and the preoperculum anterodorsa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Length
Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish measured from the tip of the snout to the posterior end of the last vertebra or to the posterior end of the midlateral portion of the hypural plate. Simply put, this measurement excludes the length of the caudal (tail) fin. * Total length (TL) is the length of a fish measured from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body. Standard length measurements are used with Teleostei (most bony fish), while total length measurements are used with Myxini (hagfish), Petromyzontiformes (lampreys), and (usually) Elasmobranchii (sharks and rays), as well as some other fishes. Total length me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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