|
Homarinus
The Cape lobster, ''Homarinus capensis'', is a species of small lobster that lives off the coast of South Africa, from Dassen Island to Haga Haga. Only a few dozen specimens are known, mostly regurgitated by reef-dwelling fish. It lives in rocky reefs, and is thought to lay large eggs that have a short larval phase, or that hatch directly as a juvenile. The species grows to a total length of , and resembles a small European or American lobster; it was previously included in the same genus, ''Homarus'', although it is not very closely related to those species, and is now considered to form a separate, monotypic genus – ''Homarinus''. Its closest relatives are the genera ''Thymops'' and ''Thymopides''. Distribution and ecology The Cape lobster is endemic to South Africa. It occurs from Dassen Island, Western Cape in the west to Haga Haga, Eastern Cape in the east, a range of . Most of the known specimens were regurgitated by fish caught on reefs at depths of . This suggests ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homarus
''Homarus'' is a genus of lobsters, which include the common and commercially significant species ''Homarus americanus'' (the American lobster) and ''Homarus gammarus'' (the European lobster). The Cape lobster, which was formerly in this genus as ''H. capensis'', was moved in 1995 to the new genus ''Homarinus''. Description ''Homarus'' is one of three extant genera of clawed lobsters to show dimorphism between claws – a specialisation into a crushing claw and a cutting claw. The other similar genera are '' Nephrops'', which is much more slender, and has grooves along the claws and the abdomen, and ''Homarinus'', the Cape lobster from South Africa, which is even smaller, and has hairy claws. tp://ftp.fao.org/docrep/fao/009/t0411e/t0411e09.pdf Subfamily Nephropinae Dana, 1852 pp. 51–86 in Holthuis (1991). While analyses of morphology suggest a close relationship between ''Homarinus'' and ''Homarus'', molecular analyses using mitochondrial DNA reveal that they are not sister ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobster
Lobsters are a family (biology), family (Nephropidae, Synonym (taxonomy), synonym Homaridae) of marine crustaceans. They have long bodies with muscular tails and live in crevices or burrows on the sea floor. Three of their five pairs of legs have claws, including the first pair, which are usually much larger than the others. Highly prized as seafood, lobsters are economically important and are often one of the most profitable commodities in coastal areas they populate. Commercially important species include two species of ''Homarus'' from the northern Atlantic Ocean and scampi (which look more like a shrimp, or a "mini lobster")—the Northern Hemisphere genus ''Nephrops'' and the Southern Hemisphere genus ''Metanephrops''. Distinction Although several other groups of crustaceans have the word "lobster" in their names, the unqualified term "lobster" generally refers to the clawed lobsters of the family Nephropidae. Clawed lobsters are not closely related to spiny lobsters o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymopides
''Thymopides'' is a genus of deep-water lobsters, comprising the two species ''Thymopides grobovi'' and ''Thymopides laurentae''. Distribution Two species are included in the genus ''Thymopides''. *''Thymopides grobovi'' is found around Heard Island and the Kerguelen Archipelago in the southern Indian Ocean at depths of . *''Thymopides laurentae'' is only known from a single hydrothermal vent on the Mid-Atlantic Ridge at a depth of (). Description ''Thymopides'' differs from related genera such as ''Homarus'', ''Homarinus'' and '' Nephrops'' in having the first pair of pereiopods of similar size and shape, rather than one "crusher" and one "cutter" claw. It differs from others, such as '' Metanephrops'' and ''Eunephrops'' by the lack of a carina behind the antennal spine, by the smaller size of some spines and by the smaller, unpigmented eyes. Taxonomy The genus was first described by R. N. Burukovsky and B. S. Averin in 1976 under the name ''Bellator'', in a paper in the ''Ru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymops
''Thymops birsteini'', the Patagonian lobsterette, is a species of lobster found around the coasts of South America, particularly the South Atlantic. It belongs to the monotypic genus ''Thymops''. Distribution ''T. birsteini'' is found on the continental shelf around South America, particularly in the Argentine Sea. In the Atlantic Ocean, it is found south of 37° south, with Uruguay representing the northern extremity of its distribution; on the Chilean (Pacific) side, it is found south of 51° south. Its range includes the areas around the Falkland Islands (''Islas Malvinas'') and areas near South Georgia, extending as far south as 57°, close to the Antarctic Peninsula. It lives at depths of . Description ''T. birsteini'' resembles a typical lobster, with two large claws, four other pairs of pereiopods, and a long pleon (tail). The carapace is granular, especially in the front half, and it bears a rostrum which divides into two points at its tip. The total length may rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portable Document Format
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.Adobe Systems IncorporatedPDF Reference, Sixth edition, version 1.23 (53 MB) Nov 2006, p. 33. Archiv/ref> Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020. PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carapace
A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron. Crustaceans In crustaceans, the carapace functions as a protective cover over the cephalothorax (i.e., the fused head and thorax, as distinct from the abdomen behind). Where it projects forward beyond the eyes, this projection is called a rostrum (anatomy), rostrum. The carapace is Calcification, calcified to varying degrees in different crustaceans. Zooplankton within the phylum Crustacea also have a carapace. These include Cladocera, ostracods, and Isopoda, isopods, but isopods only have a developed "cephalic shield" carapace covering the head. Arachnids In arachnids, the carapace is formed by the fusion of prosomal tergites into a single Plate (animal anatomy), plate which carries the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homarus Americanus
The American lobster (''Homarus americanus'') is a species of lobster found on the Atlantic coast of North America, chiefly from Labrador to New Jersey. It is also known as Atlantic lobster, Canadian lobster, true lobster, northern lobster, Canadian Reds, or Maine lobster. It can reach a body length of , and a mass of over , making it not only the heaviest crustacean in the world, but also the heaviest of all living arthropod species. Its closest relative is the European lobster ''Homarus gammarus'', which can be distinguished by its coloration and the lack of spines on the underside of the rostrum. American lobsters are usually bluish green to brown with red spines, but several color variations have been observed. Distribution ''Homarus americanus'' is distributed along the Atlantic coast of North America, from Labrador in the north to Cape Hatteras, North Carolina, in the south. South of New Jersey, the species is uncommon, and landings in Delaware, Maryland, Virginia and North ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe and Asia from the "New World" of the Americas in the European perception of the World. The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally between Europe and Africa to the east, and North and South America to the west. As one component of the interconnected World Ocean, it is connected in the north to the Arctic Ocean, to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south (other definitions describe the Atlantic as extending southward to Antarctica). The Atlantic Ocean is divided in two parts, by the Equatorial Counter Current, with the North(ern) Atlantic Ocean and the South(ern) Atlantic Ocean split at about 8°N. Scientific explorations of the A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lobster Trap
A lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. In Scotland (chiefly in the north), the word creel is used to refer to a device used to catch lobsters and other crustaceans. A lobster trap can hold several lobsters. Lobster traps can be constructed of wire and wood, or metal and netting or rigid plastic. An opening permits the lobster to enter a tunnel of netting or other one-way device. Pots are sometimes constructed in two parts, called the "chamber" or "kitchen", where there is bait, and exits into the "parlour", which prevents escape. Lobster pots are usually dropped to the sea floor, one or more at a time, sometimes up to 40 or more, and are marked by a buoy so they can be picked up later. Description The trap can consist of a wood frame surrounded by mesh. The majority of the newer traps found in the Northeast of the US and the Canadian Maritimes consist of a plastic-coated metal frame. A piece of bait, ... [...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] |
Dredging
Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing dams, dikes, and other controls for streams and shorelines; and recovering valuable mineral deposits or marine life having commercial value. In all but a few situations the excavation is undertaken by a specialist floating plant, known as a dredger. Dredging is carried out in many different locations and for many different purposes, but the main objectives are usually to recover material of value or use, or to create a greater depth of water. Dredges have been classified as suction or mechanical. Dredging has significant environmental impacts: it can disturb marine sediments, leading to both short- and long-term water pollution, destroy important seabed ecosystems, and can release human-sourced toxins captured in the sediment. Description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reef
A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock outcrops, etc.—but there are also reefs such as the coral reefs of tropical waters formed by biotic processes dominated by corals and coralline algae, and artificial reefs such as shipwrecks and other anthropogenic underwater structures may occur intentionally or as the result of an accident, and sometimes have a designed role in enhancing the physical complexity of featureless sand bottoms, to attract a more diverse assemblage of organisms. Reefs are often quite near to the surface, but not all definitions require this. Earth's largest coral reef system is the Great Barrier Reef in Australia, at a length of over . Biotic There is a variety of biotic reef types, including oyster reefs and sponge reefs, but the most massive and widely ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.png "Click for more on -> Dredging")
