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Dinoflagellate
The dinoflagellates ( Greek δῖνος ''dinos'' "whirling" and Latin ''flagellum'' "whip, scourge") are a monophyletic group of single-celled eukaryotes constituting the phylum Dinoflagellata and are usually considered algae. Dinoflagellates are mostly marine plankton, but they also are common in freshwater habitats. Their populations vary with sea surface temperature, salinity, and depth. Many dinoflagellates are photosynthetic, but a large fraction of these are in fact mixotrophic, combining photosynthesis with ingestion of prey ( phagotrophy and myzocytosis). In terms of number of species, dinoflagellates are one of the largest groups of marine eukaryotes, although substantially smaller than diatoms. Some species are endosymbionts of marine animals and play an important part in the biology of coral reefs. Other dinoflagellates are unpigmented predators on other protozoa, and a few forms are parasitic (for example, '' Oodinium'' and '' Pfiesteria''). Some dinoflagellat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinocyst
Dinocysts or dinoflagellate cysts are typically 15 to 100 µm in diameter and produced by around 15–20% of living dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts. History The first person to recognize fossil dinoflagellates was Christian Gottfried Ehrenberg, who reported his discovery in a paper presented to the Berlin Academy of Sciences in July 1836. He had observed clearly tabulate dinoflagellates in thin flakes of Cretaceous flint and considered those dinoflagellates to have been silicified. Along with them, and of comparable size, were spheroidal to ovoidal bodies bearing an array of spines or tubes of variable character. Ehrenberg interpreted these as being originally siliceous and thought them to be desmids (freshwater conjugating algae), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Life
Marine life, sea life, or ocean life is the plants, animals and other organisms that live in the salt water of seas or oceans, or the brackish water of coastal estuaries. At a fundamental level, marine life affects the nature of the planet. Marine organisms, mostly microorganisms, produce oxygen and sequester carbon. Marine life in part shape and protect shorelines, and some marine organisms even help create new land (e.g. coral building reefs). Most life forms evolved initially in marine habitats. By volume, oceans provide about 90% of the living space on the planet. The earliest vertebrates appeared in the form of fish, which live exclusively in water. Some of these evolved into amphibians, which spend portions of their lives in water and portions on land. One group of amphibians evolved into reptiles and mammals and a few subsets of each returned to the ocean as sea snakes, sea turtles, seals, manatees, and whales. Plant forms such as kelp and other algae grow i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratium
The genus ''Ceratium'' is restricted to a small number (about 7) of freshwater dinoflagellate species. Previously the genus contained also a large number of marine dinoflagellate species. However, these marine species have now been assigned to a new genus called ''Tripos''. ''Ceratium'' dinoflagellates are characterized by their armored plates, two flagella, and horns. They are found worldwide and are of concern due to their blooms. Taxonomy The genus was originally published in 1793 by Shrank, F. von Paula. The taxonomy of C''eratium'' varies among several sources. One source states the taxonomy as: Kingdom Chromista, Phylum Miozoa, Class Dinophyceae, Order Gonyaulacales, and Family Ceratiaceae. Another source lists the taxonomy as Kingdom Protozoa, Phylum Dinoflagellata, Class Dinophyceae, Order Gonyaulacales, and Family Ceratiaceae. The taxonomic information listed on the right includes Kingdom Chromalveolate. Thus, sources disagree on the higher levels of classification, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syndiniophyceae
The Syndiniales are an order (biology), order of early branching dinoflagellates (also known as Marine Alveolates, "MALVs"), found as Parasitism, parasites of crustaceans, fish, algae, cnidarians, and protists (ciliates, radiolarians, other dinoflagellates). The trophozoite, trophic form is often multinucleate, and ultimately divides to form motile spores, which have two flagellum, flagella in typical dinoflagellate arrangement. They lack a theca and chloroplasts, and unlike all other orders, the cell nucleus, nucleus is never a dinokaryon. A well-studied example is ''Amoebophrya'', which is a parasite of other dinoflagellates and may play a part in ending algal bloom, red tides. Several MALV groups have been assigned to Syndiniales; recent studies, however, show paraphyly of MALVs suggesting that only those groups that branch as sister to dinokaryotes ('core dinoflagellates') belong to Syndiniales. Taxonomy * class (biology), Class Syndiniophyceae Loeblich III, 1976 [Syndinea] ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noctilucales
The Noctilucales are an order of marine dinoflagellates. They differ from most others in that the mature cell is diploid and its nucleus does not show a dinokaryotic organization. They show gametic meiosis. Characteristics These cells are very large, from 0.2 to 2 millimetres in diameter, and are filled with large buoyant vacuoles. Some may contain symbiotic green algae, but there are no chloroplasts. Instead, they feed on other plankton, and there is usually a special flagellum involved in ingestion. Noctilucales reproduce mainly by fission, but sexual reproduction also occurs. Each cell produces numerous gametes, which resemble more typical athecate dinoflagellates and have the dinokaryotic nuclei. Evidence suggests that they diverged from most other dinoflagellates early on, and they are generally placed in their own class. Taxonomy * Class Noctiluciphyceae Fensome et al. 1993 octilucae Haeckel 1866; Noctilucea Haeckel 1866 stat. nov.; Cystoflagellata Haeckel 1873 stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pfiesteria
''Pfiesteria'' is a genus of heterotrophic dinoflagellates that has been associated with harmful algal blooms and fish kills. ''Pfiesteria'' complex organisms (PCOs) were claimed to be responsible for large fish kills in the 1980s and 1990s on the coast of North Carolina and in tributaries of the Chesapeake Bay. In reaction to the toxic outbreaks, six states along the US east coast have initiated a monitoring program to allow for rapid response in the case of new outbreaks and to better understand the factors involved in ''Pfiesteria'' toxicity and outbreaks. New molecular detection methods have revealed that ''Pfiesteria'' has a worldwide distribution. Discovery and naming ''Pfiesteria'' was discovered in 1988 by North Carolina State University researchers JoAnn Burkholder and Ed Noga. The genus was named after Lois Ann Pfiester (1936–1992), a biologist who did much of the early research on dinoflagellates. Species There are two species described, ''Pfiesteria piscicida'' (fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plankton
Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales. Marine plankton include bacteria, archaea, algae, protozoa and drifting or floating animals that inhabit the saltwater of oceans and the brackish waters of estuaries. Freshwater plankton are similar to marine plankton, but are found in the freshwaters of lakes and rivers. Plankton are usually thought of as inhabiting water, but there are also airborne versions, the aeroplankton, that live part of their lives drifting in the atmosphere. These include plant spores, pollen and wind-scattered seeds, as well as microorganisms swept into the air from terrestrial dust storms and oceanic plankton swept into the air by sea spray. Though man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyrrhea
''Oxyrrhis'' is a genus of dinoflagellates. It includes the species '' Oxyrrhis marina''. It is sometimes considered to be a monotypic genus In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ....Lowe, C. D., et al. (2011)Who is ''Oxyrrhis marina''? Morphological and phylogenetic studies on an unusual dinoflagellate.''Journal of Plankton Research'' 33(4) 555-67. Some sources assign the species '' Oxyrrhis parasitica'' and '' O. phaeocysticola'', as well.Guiry, M. D. in Guiry, M. D. & G. M. Guiry. 2013''Oxyrrhis''.AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. Accessed on 10 June 2013. Classification Class Oxyrrhea Cavalier-Smith 1987 xyrrhidophyceae; Oxyrrhia Cavalier-Smith & Chao 2004* Order Oxyrrhinida Cavalier-Smith 1993 xyrrhinales Sourn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinophyceae
Dinophyceae is a class of dinoflagellates. Taxonomy * Class Dinophyceae Pascher 1914 eridinea Ehrenberg 1830 stat. nov. Wettstein; Blastodiniphyceae Fensome et al. 1993 orthog. emend.** Order Haplozoonales aplozooidea Poche 1913*** Family Haplozoonaceae Chatton 1920 ** Order Akashiwales *** Family Akashiwaceae ** Order Blastodiniales Chatton 1906 lastodinida Chatton 1906*** Family Blastodiniaceae Cavers 1913 ** Order Apodiniales *** Family Apodiniaceae Chatton 1920 ** Order Dinotrichales Pascher 1914 *** Family Crypthecodiniaceae Biecheler 1938 ex Chatton 1952 *** Family Dinotrichaceae Pascher 1914 ** Order Phytodiniales T. Christ. 1962 ex Loeblich 1970 inococcales Pascher 1914; Suessiales Fensome & al. 1993; Dinamoebales *** Family † Suessiaceae Fensome et al. 1993 *** Family Phytodiniaceae Klebs 1912 inococcaceae Fott 1960; Hemidiniaceae Bourrelly 1970; Borghiellaceae Moestrup, Lindberg & Daugbjerg 2009*** Family Symbiodiniaceae Fensome & al. 1993 ooxant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water – hence the name ''photosynthesis'', from the Greek ''phōs'' (), "light", and ''synthesis'' (), "putting together". Most plants, algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the Earth's atmosphere, and supplies most of the energy necessary for life on Earth. Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centers that contain green chlorophyll (and other colored) pigments/chromophor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as ''Chlorella,'' ''Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and autotrophic (they generate food internally) and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the ''Charophyta'', a division of green algae which includes, for example, ''Spirogyra'' and stoneworts. No definition of algae is generally accepted. One definition is that algae "have chlorophyll ''a'' as their primary photosynthetic pigment and lack a sterile covering of cells around their re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oodinium
''Oodinium'' is a genus of parasitic dinoflagellates. Their hosts are salt- and fresh-water fish, causing a type of fish velvet disease (also called gold dust disease). One species has also been recorded on various cnidarians. The host typically develops a yellow or gold "dust" scattered on its head, fins and body. At this stage, the infestation is already severe. The attack usually starts at the gills, at which stage it is difficult to observe. The host fish is irritated, and often sporadically darts about or rubs itself against rocks. The yellowish spots are more vivid under a strong light source. It is very similar to '' Ichthyophthirius'', though the oodinium spots are yellowish and smaller. The life cycle of oodinium starts as a dinospore that swims in the water to look for a suitable host. As it attaches itself onto the host skin, it forms a hard shell protecting itself against the outside environment while it is eating the fish skin cells. This is the cyst stage seen a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
