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Genus: | Emiliania Hay & Mohler |
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Emiliania is a global coccolithophorid genus.
The genus name of Emiliania is in honour of Cesare Emiliani (1922–1995), who was an Italian-American scientist, geologist, micropaleontologist, and founder of paleoceanography, developing the timescale of marine isotope stages. [1]
The genus was circumscribed by Hanspeter Mohler and William Winn Hay in Trans. Gulf Coast Ass. Geol. Soc. Vol.17 on page 447 in 1967.
It formerly included the species Emiliania huxleyi , [2] now called Gephyrocapsa huxleyi . [3]
Coccolithophores, or coccolithophorids, are single-celled organisms which are part of the phytoplankton, the autotrophic (self-feeding) component of the plankton community. They form a group of about 200 species, and belong either to the kingdom Protista, according to Robert Whittaker's five-kingdom system, or clade Hacrobia, according to a newer biological classification system. Within the Hacrobia, the coccolithophores are in the phylum or division Haptophyta, class Prymnesiophyceae. Coccolithophores are almost exclusively marine, are photosynthetic, and exist in large numbers throughout the sunlight zone of the ocean.
The haptophytes, classified either as the Haptophyta, Haptophytina or Prymnesiophyta, are a clade of algae.
Coccoliths are individual plates or scales of calcium carbonate formed by coccolithophores and cover the cell surface arranged in the form of a spherical shell, called a coccosphere.
Gephyrocapsa huxleyi, formerly called Emiliania huxleyi, is a species of coccolithophore found in almost all ocean ecosystems from the equator to sub-polar regions, and from nutrient rich upwelling zones to nutrient poor oligotrophic waters. It is one of thousands of different photosynthetic plankton that freely drift in the photic zone of the ocean, forming the basis of virtually all marine food webs. It is studied for the extensive blooms it forms in nutrient-depleted waters after the reformation of the summer thermocline. Like other coccolithophores, E. huxleyi is a single-celled phytoplankton covered with uniquely ornamented calcite disks called coccoliths. Individual coccoliths are abundant in marine sediments although complete coccospheres are more unusual. In the case of E. huxleyi, not only the shell, but also the soft part of the organism may be recorded in sediments. It produces a group of chemical compounds that are very resistant to decomposition. These chemical compounds, known as alkenones, can be found in marine sediments long after other soft parts of the organisms have decomposed. Alkenones are most commonly used by earth scientists as a means to estimate past sea surface temperatures.
Vernonia is a genus of about 350 species of forbs and shrubs in the family Asteraceae. Some species are known as ironweed. Some species are edible and of economic value. They are known for having intense purple flowers. There have been numerous distinct subgenera and subsections named in this genus, and some botanists have divided the genus into several distinct genera. For instance, the Flora of North America recognizes only about twenty species in Vernoniasensu stricto, seventeen of which are in North America north of Mexico, with the others being found in South America.
Alkenones are long-chain unsaturated methyl and ethyl n-ketones produced by a few phytoplankton species of the class Prymnesiophyceae. Alkenones typically contain between 35 and 41 carbon atoms and with between two and four double bonds. Uniquely for biolipids, alkenones have a spacing of five methylene groups between double bonds, which are of the less common E configuration. The biological function of alkenones remains under debate although it is likely that they are storage lipids. Alkenones were first described in ocean sediments recovered from Walvis Ridge and then shortly afterwards in cultures of the marine coccolithophore Gephyrocapsa huxleyi. The earliest known occurrence of alkenones is during the Aptian 120 million years ago. They are used in organic geochemistry as a proxy for past sea surface temperature.
Hyperodapedon is an extinct genus of rhynchosaur reptiles which lived during Late Triassic period. Like other rhynchosaurs, it was an heavily built archosauromorph, distantly related to archosaurs such as crocodilians and dinosaurs. Hyperodapedon in particular was part of the subfamily Hyperodapedontinae, a specialized rhynchosaurian subgroup with broad skulls, beaked snouts, and crushing tooth plates on the roof of the mouth.
Coccolithovirus is a genus of giant double-stranded DNA virus, in the family Phycodnaviridae. Algae, specifically Emiliania huxleyi, a species of coccolithophore, serve as natural hosts. There is only one described species in this genus: Emiliania huxleyi virus 86.
Phycodnaviridae is a family of large (100–560 kb) double-stranded DNA viruses that infect marine or freshwater eukaryotic algae. Viruses within this family have a similar morphology, with an icosahedral capsid. As of 2014, there were 33 species in this family, divided among 6 genera. This family belongs to a super-group of large viruses known as nucleocytoplasmic large DNA viruses. Evidence was published in 2014 suggesting that specific strains of Phycodnaviridae might infect humans rather than just algal species, as was previously believed. Most genera under this family enter the host cell by cell receptor endocytosis and replicate in the nucleus. Phycodnaviridae play important ecological roles by regulating the growth and productivity of their algal hosts. Algal species such Heterosigma akashiwo and the genus Chrysochromulina can form dense blooms which can be damaging to fisheries, resulting in losses in the aquaculture industry. Heterosigma akashiwo virus (HaV) has been suggested for use as a microbial agent to prevent the recurrence of toxic red tides produced by this algal species. Phycodnaviridae cause death and lysis of freshwater and marine algal species, liberating organic carbon, nitrogen and phosphorus into the water, providing nutrients for the microbial loop.
Emiliana is a feminine name of Italian origin. It can refer to:
Duboscquella is a genus of dinoflagellates.
Chlorophyll c refers to forms of chlorophyll found in certain marine algae, including the photosynthetic Chromista and dinoflagellates. These pigments are characterized by their unusual chemical structure, with a porphyrin as opposed to the chlorin as the core; they also do not have an isoprenoid tail. Both these features stand out from the other chlorophylls commonly found in algae and plants.
Marseillevirus is a genus of viruses, in the family Marseilleviridae. There are two species in this genus. It is the prototype of a family of nucleocytoplasmic large DNA viruses (NCLDV) of eukaryotes. It was isolated from amoeba.
Clymenia is a small genus of flowering plants in the family Rutaceae with two species. The genus is often included in Citrus.
Methylophaga thiooxydans is a methylotrophic bacterium that requires high salt concentrations for growth. It was originally isolated from a culture of the algae Emiliania huxleyi, where it grows by breaking down dimethylsulfoniopropionate from E. hexleyi into dimethylsulfide and acrylate. M. thiooxydans has been implicated as a dominant organism in phytoplankton blooms, where it consumes dimethylsulfide, methanol and methyl bromide released by dying phytoplankton. It was also identified as one of the dominant organisms present in the plume following the Deepwater Horizon oil spill, and was identified as a major player in the breakdown of methanol in coastal surface water in the English Channel.
Particulate inorganic carbon (PIC) can be contrasted with dissolved inorganic carbon (DIC), the other form of inorganic carbon found in the ocean. These distinctions are important in chemical oceanography. Particulate inorganic carbon is sometimes called suspended inorganic carbon. In operational terms, it is defined as the inorganic carbon in particulate form that is too large to pass through the filter used to separate dissolved inorganic carbon.
The Great Calcite Belt (GCB) refers to a region of the ocean where there are high concentrations of calcite, a mineral form of calcium carbonate. The belt extends over a large area of the Southern Ocean surrounding Antarctica. The calcite in the Great Calcite Belt is formed by tiny marine organisms called coccolithophores, which build their shells out of calcium carbonate. When these organisms die, their shells sink to the bottom of the ocean, and over time, they accumulate to form a thick layer of calcite sediment.
Ana María Gayoso was an Argentine marine biologist, a specialist in study of marine phytoplankton, best known for being the first scientist to describe phytoplankton in the Bahía Blanca Estuary, and to initiate the sustained long-term oceanographic dataset in this ecosystem. She made significant contributions to the understanding of harmful algal blooms caused by toxic dinoflagellate species in the Patagonian gulfs, and was the first scientist to describe high abundances of the coccolithophore Emiliania huxleyi in the Argentine Sea, a key component in the primary productivity along the Patagonian Shelf Break front in the SW South Atlantic. She started the most extensive (1978-present) long-term database of phytoplankton and physico-chemical variables in South America, in a fixed monitoring site in the Bahía Blanca Estuary. She died on 28 December 2004 in Puerto Madryn.
Maureen Hatcher Conte is biogeochemist known for her work using particles to define the long-term cycling of chemical compounds in seawater.
Virivore comes from the English prefix viro- meaning virus, derived from the Latin word for poison, and the suffix -vore from the Latin word vorare, meaning to eat, or to devour; therefore, a virivore is an organism that consumes viruses. Virivory is a well-described process in which organisms, primarily heterotrophic protists, but also some metazoans consume viruses.