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White Ghost Catshark
The white ghost catshark (''Apristurus aphyodes'') is a shark of the catshark family Scyliorhinidae found in deep water in the northeast Atlantic between latitudes 57°N and 58°N. A deep-water catshark known from the eastern North Atlantic from depths of 1,014 to 1,800 m, it is known from only a limited number of specimens. It reaches a maximum of 54 cm or 1.7 ft total length which is a medium size for the ''Apristurus'' genus. Description and morphology The white ghost catshark has a slender and cylindrical body with a relatively long and flattened snout. It is distinguished from the other 10 North Atlantic ''Apristurus'' species by the following. It has a uniform whitish coloration and large oval eyes with a weak subocular fold. Its snout is bell shaped and contains numerous visible pores making up ampullae of Lorenzini on the dorsal and ventral side of the snout. Its preorbital snout length (where the snout intersects its eyes) equals half of its head length. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kazuhiro Nakaya
is a Japanese marine scientist and ichthyologist. He graduated from Hokkaido University with a BA in 1968 and with a PhD in 1972. He is professor of Marine Environment and Resources at the Marine Laboratory for Biodiversity. He specializes in taxonomy and evolution of sharks, rays, chimaeras, and Lake Tanganyikan fish. He is the author of many articles and books on sharks and fish. In 1995 he was put in charge of dissecting and preparing the 7th specimen of the very rare megamouth shark. Research Field New species described by Nakaya and colleagues Family Scyliorhinidae (Cat sharks) Whitebody catshark ('' Apristurus albisoma'' Nakaya & Séret, 1999)br /> Largehead catshark (''Apristurus ampliceps'' Sasahara, Sato & Nakaya, 2008) Catshark ('' Apristurus aphyodes'' Nakaya & Stehmann, 1998) Southern catshark ('' Apristurus australis'' Sato, Nakaya & Yorozu, 2008) Shortbelly catshark ('' Apristurus breviventralis'' Kawauchi, Weigmann & Nakaya, 2014) Softbody catshark ('' Aprist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bryozoa
Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding. Most marine bryozoans live in tropical waters, but a few are found in oceanic trenches and polar waters. The bryozoans are classified as the marine bryozoans (Stenolaemata), freshwater bryozoans (Phylactolaemata), and mostly-marine bryozoans (Gymnolaemata), a few members of which prefer brackish water. 5,869living species are known. At least two genera are solitary (''Aethozooides'' and ''Monobryozoon''); the rest are colonial. The terms Polyzoa and Bryozoa were introduced in 1830 and 1831, respectively. Soon after it was named, another group of animals was discovered whose filtering mechanism looked similar, so it was included in Bryozoa until 1869, when the two groups were no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasmobranchii
Elasmobranchii () is a subclass of Chondrichthyes or cartilaginous fish, including sharks (superorder Selachii), rays, skates, and sawfish (superorder Batoidea). Members of this subclass are characterised by having five to seven pairs of gill clefts opening individually to the exterior, rigid dorsal fins and small placoid scales on the skin. The teeth are in several series; the upper jaw is not fused to the cranium, and the lower jaw is articulated with the upper. The details of this jaw anatomy vary between species, and help distinguish the different elasmobranch clades. The pelvic fins in males are modified to create claspers for the transfer of sperm. There is no swim bladder; instead, these fish maintain buoyancy with large livers rich in oil. The definition of the clade is unclear with respect to fossil chondrichthyans. It has been used by different authors as equivalent to Neoselachii (the clade including modern sharks and rays and their last common ancestor) or for al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trawling
Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch different species of fishes or sometimes targeted species. Trawls are often called towed gear or dragged gear. The boats that are used for trawling are called trawlers or draggers. Trawlers vary in size from small open boats with as little as 30 hp (22 kW) engines to large factory trawlers with over 10,000 hp (7.5 MW). Trawling can be carried out by one trawler or by two trawlers fishing cooperatively (pair trawling). Trawling can be contrasted with trolling. While trawling involves a net and is typically done for commercial usage, trolling instead involves a reed, rod and a bait or a lure and is typically done for recreational purposes. Trawling is also commonly used as a scientific sampling, or survey, method. Bottom vs. midwater trawling ... [...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] |
Blue Whiting
The blue whiting (''Micromesistius poutassou'') one of the two species in the genus '' Micromesistius'' in the family Gadidae, which also contains cod, haddock, whiting, and pollock. It is common in the northeast Atlantic Ocean from Morocco to Iceland and Spitsbergen. It also occurs in the northern parts of the Mediterranean, where it may be locally abundant. Blue whiting also occur in the northwest Atlantic Ocean between Canada and Greenland, but is considered rare. It has a long, narrow body and a silvery underbody. The fish can attain a length of more than 40 cm. The average length of blue whiting caught off the west shores of the UK is 31 cm. A related species, southern blue whiting, ''Micromesistius australis'', occurs in the Southern Hemisphere. Fisheries Exploitation of blue whiting only started in the 1970s. The species, in the last decades, has become increasingly important to the fishing industries of northern European countries, including Russia. Catche ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anchovy
An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water, and some in South America are restricted to fresh water. More than 140 species are placed in 17 genera; they are found in the Atlantic, Indian and Pacific Oceans, and in the Black Sea and the Mediterranean Sea. Anchovies are usually classified as oily fish. Genera Characteristics Anchovies are small, green fish with blue reflections due to a silver-colored longitudinal stripe that runs from the base of the caudal (tail) fin. They range from in adult length, and their body shapes are variable with more slender fish in northern populations. The snout is blunt with tiny, sharp teeth in both jaws. The snout contains a unique rostral organ, believed to be electro-sensory in nature, although its exact function is unknown. The mouth is larger than that of herrings and silversides, two fish which anchovies closely resemble in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OSPAR Convention
The Convention for the Protection of the Marine Environment of the North-East Atlantic or OSPAR Convention is the current legislative instrument regulating international cooperation on environmental protection in the North-East Atlantic. Work carried out under the convention is managed by the OSPAR Commission, which is made up of representatives of the Governments of the 15 signatory nations, and representatives of the European Commission, representing the European Union. The OSPAR Convention was concluded at Paris on 22 September 1992. It combines and up-dates the 1972 Oslo Convention on dumping waste at sea and the 1974 Paris Convention on land-based sources of marine pollution. The name is likewise a combination of "Oslo" and "Paris". History The Convention for the Protection of the Marine Environment of the North-East Atlantic was opened for signature at the Ministerial Meeting of the Oslo and Paris Commissions in Paris on 22 September 1992. The Convention has been si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviparity
Oviparous animals are animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, most reptiles, and all pterosaurs, dinosaurs (including birds), and monotremes. In traditional usage, most insects (one being ''Culex pipiens'', or the common house mosquito), molluscs, and arachnids are also described as oviparous. Modes of reproduction The traditional modes of reproduction include oviparity, taken to be the ancestral condition, traditionally where either unfertilised oocytes or fertilised eggs are spawned, and viviparity traditionally including any mechanism where young are born live, or where the development of the young is supported by either parent in or on any part of their body. However, the biologist Thierry Lodé recently divided the traditional category of oviparous reproduction into two modes that he named ovuliparity and (true) oviparity respectively. He distinguished the tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electroreception
Electroreception and electrogenesis are the closely-related biological abilities to perceive electrical stimuli and to generate electric fields. Both are used to locate prey; stronger electric discharges are used in a few groups of fishes to stun prey. The capabilities are found almost exclusively in aquatic or amphibious animals, since water is a much better conductor of electricity than air. In passive electrolocation, objects such as prey are detected by sensing the electric fields they create. In active electrolocation, fish generate a weak electric field and sense the different distortions of that field created by objects that conduct or resist electricity. Active electrolocation is practised by two groups of weakly electric fish, the Gymnotiformes (knifefishes) and the Mormyridae (elephantfishes), and by ''Gymnarchus niloticus'', the African knifefish. An electric fish generates an electric field using an electric organ, modified from muscles in its tail. The field is ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rockall Trough
The Rockall Trough ( gd, Clais Sgeir Rocail) is a deep-water bathymetric feature to the northwest of Scotland and Ireland, running roughly from southwest to northeast, flanked on the north by the Rockall Plateau and to the south by the Porcupine Seabight. At the northern end, the channel is bounded by the Wyville-Thomson Ridge, named after Charles Wyville Thomson, professor of zoology at the University of Edinburgh and driving force behind the Challenger Expedition. At the southern end, the trough opens into the Porcupine abyssal plain. The Rockall Basin (also known as the Hatton Rockall Basin) is a large (c. 800 km by 150 km) sedimentary basin that lies beneath the trough. Both are named after Rockall, a rocky islet lying 301.4 km west of St Kilda. Features of the Rockall Plateau have been officially named after features of Middle-earth in the fiction of J. R. R. Tolkien, e.g. Eriador Seamount, Rohan Seamount, Gondor Seamount, Fangorn Bank, Edoras Bank, Lorie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ampullae Comparison Of Apristurus Species From Researchgate Article
An ampulla (; ) was, in Ancient Rome, a small round vessel, usually made of glass and with two handles, used for sacred purposes. The word is used of these in archaeology, and of later flasks, often handle-less and much flatter, for holy water or holy oil in the Middle Ages, often bought as souvenirs of pilgrimages, such as the metal Monza ampullae of the 6th century. Materials include glass, ceramics and metal. Unguentarium is a term for a bottle believed to have been used to store perfume, and there is considerable overlap between the two terms, one defined by shape and the other by purpose. The glass Holy Ampulla was part of the French coronation regalia and believed to have divine origins. Similar, but far more recent, is the Ampulla in the British regalia, a hollow, gold, eagle-shaped vessel from which the anointing oil is poured by the Archbishop of Canterbury at the anointing of a new British sovereign at their coronation A coronation is the act of placement or b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
