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Euchaetidae
Euchaetidae is a family of marine copepods. The family is cosmopolitan and occurs in all the oceans, including the Southern and Arctic Oceans. Euchaetidae are medium to large-sized copepods. Genera There are two genera with in total 114 species: Ecology ''Euchaeta'' are mostly epipelagic whereas ''Paraeuchaeta'' are mostly bathypelagic. Where more than one species occurs, congeneric species (or life stages of a single species, as observed for ''Paraeuchaeta antarctica'') may partition the water column, whereas species representing different genera that occur at similar depths differ in dietary preferences. ''Paraeuchaeta'' can be important predators of fish larvae. Their mode of predation is " drift and wait". The dominant euchaetid in the Southern Ocean is ''Paraeuchaeta antarctica''. It is a dominant predator there, and its fatty acid profile suggests that it mostly preys upon herbivorous calanid copepods. In the Weddell Sea, it contributes as much as 11–18% to total mesozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calanoida
Calanoida is an order of copepods, a group of arthropods commonly found as zooplankton. The order includes around 46 families with about 1800 species of both marine and freshwater copepods between them. Description Calanoids can be distinguished from other planktonic copepods by having first antennae at least half the length of the body and biramous second antennae. However, their most distinctive anatomical trait is the presence of a joint between the fifth and sixth body segments. The largest specimens reach long, but most do not exceed long. Classification Calanoida contains the following families, as well as the genus '' Microdisseta'' (which is currently ''incertae sedis''); * Acartiidae * Aetideidae * Arctokonstantinidae * Arietellidae * Augaptilidae * Bathypontiidae * Calanidae * Calocalanidae * Candaciidae * Centropagidae * Clausocalanidae * Diaixidae * Diaptomidae * Discoidae * Epacteriscidae * Eucalanidae * Euchaetidae * Fosshageniidae * Heterorha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilhelm Giesbrecht
Wilhelm Giesbrecht (1854–1913) was a Prussian zoologist, specialising in copepods, during the "golden age of copepodology". Giesbrecht was born in Gdańsk in 1854, and was educated in Kiel, where in 1881 he earned a Ph.D. in Baltic copepods under Professor Karl Möbius. He then moved to Naples to work at the zoological station there, staying there for the remainder of his life. His most famous work is the 1892 monograph Systematik und Faunistik der pelagischen Copepoden des Golfes von Neapel und der angrenzenden Meeres-Abschnitte' ("Systematics and faunistics of the pelagic copepods of the Gulf of Naples and neighbouring seas"). In 1904, at the request of Anton Dohrn, Giesbrecht was made an honorary professor. He is commemorated in a number of species names: *''Prostheceraeus giesbrechtii'' Lang, 1884 *'' Buntonia giesbrechti'' (G. W. Müller, 1894) *'' Onchocorycaeus giesbrechti'' (F. Dahl, 1894) *''Stenhelia giesbrechti'' T. & A. Scott, 1896 *'' Pseudocyclopia giesbrechti'' ... [...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 opi ... [...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. Some species are planktonic (inhabiting sea waters), some are 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 biodiversity indicators. As with other crustaceans, copepods have a larval form. For copepods, the egg hatches into a nauplius form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult and then, after more molts, achieves adult development. The nauplius form is so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epipelagic
The photic zone, euphotic zone, epipelagic zone, or sunlight zone is the uppermost layer of a body of water that receives sunlight, allowing phytoplankton to perform photosynthesis. It undergoes a series of physical, chemical, and biological processes that supply nutrients into the upper water column. The photic zone is home to the majority of aquatic life due to the activity (primary production) of the phytoplankton. Photosynthesis in photic zone In the photic zone, the photosynthesis rate exceeds the respiration rate. This is due to the abundant solar energy which is used as an energy source for photosynthesis by primary producers such as phytoplankton. These phytoplankton grow extremely quickly because of sunlight's heavy influence, enabling it to be produced at a fast rate. In fact, ninety five percent of photosynthesis in the ocean occurs in the photic zone. Therefore, if we go deeper, beyond the photic zone, such as into the compensation point, there is little to no p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathypelagic
The bathypelagic zone or bathyal zone (from Greek βαθύς (bathýs), deep) is the part of the open ocean that extends from a depth of below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The bathypelagic is known as the midnight zone because of the lack of sunlight; this feature does not allow for photosynthesis-driven primary production, preventing growth of phytoplankton or aquatic plants. Although larger by volume than the photic zone, our knowledge of the bathypelagic zone remains limited by our ability to explore the deep ocean. Physical characteristics The bathypelagic zone is characterized by a nearly constant temperature of approximately and a salinity range of 33-35 g/kg. This region has little to no light, because sunlight does not reach this deep in the ocean and bioluminescence is limited. The hydrostatic pressure in this zone ranges 100-400 atmospheres (atm), due to the increase of 1 atm for every 10 m depth. It is bel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambush Predator
Ambush predators or sit-and-wait predators are carnivorous animals that capture or trap prey via stealth, luring or by (typically instinctive) strategies utilizing an element of surprise. Unlike pursuit predators, who chase to capture prey using sheer speed or endurance, ambush predators avoid fatigue by staying in concealment, waiting patiently for the prey to get near, before launching a sudden overwhelming attack that quickly incapacitates and captures the prey. The ambush is often opportunistic, and may be set by hiding in a burrow, by camouflage, by aggressive mimicry, or by the use of a trap (e.g. a web). The predator then uses a combination of senses to detect and assess the prey, and to time the strike. Nocturnal ambush predators such as cats and snakes have vertical slit pupils helping them to judge the distance to prey in dim light. Different ambush predators use a variety of means to capture their prey, from the long sticky tongues of chameleons to the expandi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Ocean
The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica. With a size of , it is regarded as the second-smallest of the five principal oceanic divisions: smaller than the Pacific, Atlantic, and Indian oceans but larger than the Arctic Ocean. Over the past 30 years, the Southern Ocean has been subject to rapid climate change, which has led to changes in the marine ecosystem. By way of his voyages in the 1770s, James Cook proved that waters encompassed the southern latitudes of the globe. Since then, geographers have disagreed on the Southern Ocean's northern boundary or even existence, considering the waters as various parts of the Pacific, Atlantic, and Indian oceans, instead. However, according to Commodore John Leech of the International Hydrographic Organization (IHO), recent oceanographic research has discovered the importance of Southe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acid
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important dietary sources of fuel for animals and important structural components for cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oily acid"). Types of fatty acids Fatty acids are classified in many ways: by length, by saturation vs unsat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weddell Sea
The Weddell Sea is part of the Southern Ocean and contains the Weddell Gyre. Its land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. The easternmost point is Cape Norvegia at Princess Martha Coast, Queen Maud Land. To the east of Cape Norvegia is the King Haakon VII Sea. Much of the southern part of the sea is covered by a permanent, massive ice shelf field, the Filchner-Ronne Ice Shelf. The sea is contained within the two overlapping Antarctic territorial claims of Argentine Antarctica, the British Antarctic Territory, and also resides partially within the Antarctic Chilean Territory. At its widest the sea is around across, and its area is around . Various ice shelves, including the Filchner-Ronne Ice Shelf, fringe the Weddell sea. Some of the ice shelves on the east side of the Antarctic Peninsula, which formerly covered roughly of the Weddell Sea, had completely disappeared by 2002. The Weddell Sea has been d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerguelen Islands
The Kerguelen Islands ( or ; in French commonly ' but officially ', ), also known as the Desolation Islands (' in French), are a group of islands in the sub-Antarctic constituting one of the two exposed parts of the Kerguelen Plateau, a large igneous province mostly submerged in the southern Indian Ocean. They are among the most isolated places on Earth, located more than from Madagascar. The islands, along with Adélie Land, the Crozet Islands, Amsterdam and Saint Paul islands, and France's Scattered Islands in the Indian Ocean, are part of the French Southern and Antarctic Lands and are administered as a separate district. The main island, Grande Terre, is in area, about three quarters of the size of Corsica, and is surrounded by a further 300 smaller islands and islets, forming an archipelago of . The climate is harsh and chilly with frequent high winds throughout the year. The surrounding seas are generally rough and they remain ice-free year-round. There are no i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
