| Tabellaria | |
|---|---|
 | |
| Tabellaria fenestrata | |
| Scientific classification | |
| (unranked): | |
| Superphylum: | |
| Class: | |
| Order: | |
| Family: | |
| Genus: | Tabellaria Ehrenberg ex F.T.Kützing |
Tabellaria is a genus of freshwater diatoms (Bacillariophyta). [1] They are cuboid in shape, and the frustules (siliceous cell walls) are attached at the corners so that the colonies assume a zigzag shape.
Mou, Daiqing; Stoermer, Eugene (1992). "SEPARATING TABELLARIA BACILLARIOPHYCEAE SHAPE GROUPS BASED ON FOURIER DESCRIPTORS" (PDF). Journal of Phycology. 28: 386–395. doi:10.1111/j.0022-3646.1992.00386.x. hdl: 2027.42/66204 .Text "is 3" ignored (help)
Potapova, Marina (October 2011). "Tabellaria vetteri: a New Diatom". Proceedings of the Academy of Natural Sciences of Philadelphia. 163 (1): 35–41. doi:10.1635/053.161.0102.
Knudson, Brenda M (July 1952). "The Diatom Genus Tabellaria: I. Taxonomy and Morphology". Annals of Botany. 16 (63): 421–440. ISSN 0305-7364.
Diatoms are a major group of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms can reach as much as a half-mile deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of fresh-water lakes.
Phaeodactylum tricornutum is a diatom. It is the only species in the genus Phaeodactylum. Unlike other diatoms P. tricornutum can exist in different morphotypes, and changes in cell shape can be stimulated by environmental conditions. This feature can be used to explore the molecular basis of cell shape control and morphogenesis. Unlike most diatoms P. tricornutum can grow in the absence of silicon, and it can survive without making silicified frustules. This provides opportunities for experimental exploration of silicon-based nanofabrication in diatoms.
In botany, a zoid or zoïd is a reproductive cell that possesses one or more flagella, and is capable of independent movement. Zoid can refer to either an asexually reproductive spore or a sexually reproductive gamete. In sexually reproductive gametes, zoids can be either male or female depending on the species. For example, some brown alga (Phaeophyceae) reproduce by producing multi-flagellated male and female gametes that recombine to form the diploid sporangia. Zoids are primarily found in some protists, diatoms, green alga, brown alga, non-vascular plants, and a few vascular plants. The most common classification group that produces zoids is the heterokonts or stramenopiles. These include green alga, brown alga, oomycetes, and some protists. The term is generally not used to describe motile, flagellated sperm found in animals. Zoid is also commonly confused for zooid which is a single organism that is part of a colonial animal.
The order Pennales is a traditional subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls of pennate diatoms, which are elongated in valve view. The valves may be linear or oval in shape, and usually bear bilaterally symmetrical ornamental patterns. These patterns are composed of a series of transverse lines that can appear as rows of dots when viewed with an optical microscope. Some pennate diatoms also exhibit a fissure along their longitudinal axis. This is known as a raphe, and is involved in gliding movements made by diatom cells; motile diatoms always possess a raphe.
The Coscinodiscophyceae are a class of diatoms. They are similar to the Centrales, a traditional, paraphyletic subdivision of the heterokont algae known as diatoms. The order is named for the shape of the cell walls of centric diatoms, which are circular or ellipsoid in valve view. The valves often bear radially symmetrical ornamental patterns that can appear as dots when viewed with an optical microscope. Some also bear spines on their valves, which may either increase cell surface area and reduce sinking, or act as a deterrent to zooplankton grazers. Unlike pennate diatoms, centric diatoms never have a raphe.
The genus Ceratium is restricted to a small number 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.
Bolidophyceae is a class of photosynthetic heterokont picophytoplankton, and consist of less than 20 known species. They are distinguished by the angle of flagellar insertion and swimming patterns as well as recent molecular analyses. Bolidophyceaes are sister taxa to the diatoms (Bacillariophyceae) but lack characteristic theca, and have been proposed as an intermediate group between the diatoms and all other heterokonts.
The genus Attheya consist of small single celled diatoms. Some of these species were earlier regarded to belong to Chaetoceros, or to Gonioceros, the taxonomic status of some of these species are still debated.
Pseudo-nitzschia is a marine planktonic diatom genus that accounts for 4.4% of pennate diatoms found worldwide. Some species are capable of producing the neurotoxin domoic acid (DA), which is responsible for the neurological disorder in humans known as amnesic shellfish poisoning (ASP). Currently, 58 species are known, 28 of which have been shown to produced DA. It was originally hypothesized that only dinoflagellates could produce harmful algal toxins, but a deadly bloom of Pseudo-nitzschia occurred in 1987 in the bays of Prince Edward Island, Canada, and led to an outbreak of ASP. Over 100 people were affected by this outbreak after consuming contaminated mussels; three people died. Since this event, no additional deaths have been attributed to ASP, though the prevalence of toxic diatoms and DA has increased worldwide. This anomaly is likely due to increased awareness of harmful algal blooms (HABs) and their implications for human and ecosystem health.
Odontella aurita is a diatom and the type species of genus Odontella. The easiest way to identify this species is by recognizing the very distinct shape of the cells belonging to this genus. Odontella aurita is cultivated industrially for human consumption due to its ability to produce up to 28% of its total lipids as Eicosapentaenoic acid (EPA), a long-chain polyunsaturated fatty acid (PUFA). PUFAs such as EPA are known to provide a variety of health benefits in humans, and are commonly obtained by fish oil. However, with the increasing concern of over-exploited fisheries, microalgae are a promising source of PUFAs as they can be grown year-round and their fatty acid profile and content are easily manipulated by growth conditions.
T. fenestrata may refer to:
Skeletonema dohrnii is a diatom. Together with S. marinoi, this species has flattened extremities of the processes of the fultoportulae, which interlock with those of succeeding valves without forming knuckles. It is a species of the genus Skeletonema that can be found in many waters across the globe. In the coastal waters of South Korea, their cell diameters are about 3 to 6 micrometers.
Skeletonema grethae is a species of diatom. Together with S. pseudocostatum, S. tropicum, and S. japonicum, it possesses external processes of its fultoportulae that have narrow tips which connect with those of sibling cells via fork-, knot-, or knuckle-like unions.
Skeletonema japonicum is a diatom. Together with S. pseudocostatum, S. tropicum, and S. grethae, it possesses external processes of its fultoportulae that have narrow tips which connect with those of sibling cells via fork-, knot-, or knuckle-like unions.
Skeletonema marinoi is a diatom. Together with S. dohrnii, this species has flattened extremities of the processes of the fultoportulae, which interlock with those of succeeding valves without forming knuckles.
Thalassiosira is a genus of centric diatoms, comprising over 100 marine and freshwater species. It is a diverse group of photosynthetic eukaryotes that make up a vital part of marine and freshwater ecosystems, in which they are key primary producers and essential for carbon cycling
Triparma is a genus of unicellular algae in the family Triparmaceae in the order Parmales. They form siliceous plates on the cell surface that aid in identification. Triparma is distinguished by its possession of three shield plates, three triradiate girdle plates, a triradiate girdle plate with notched ends, and a small ventral plate. It was first described by Booth & Marchant in 1987 and the holotype is Triparma columacea.
The Parmales are an order of marine microalgae within the Bolidophyceae class. They are found worldwide and characterized by a cell wall composed of 5-8 interlocking silica plates with distinct forms. They were initially thought to be loricate choanoflagellates but were shown to be a separate phyla entirely upon the discovery of chloroplasts, placing it among the photosynthetic stramenopiles.
Cyclotella is a genus of diatoms often found in oligotrophic environments, both marine and fresh water. It is in the family Stephanodiscaceae and the order Thalassiosirales. The genus was first discovered in the mid 1800s and since then has become an umbrella genus for nearly 100 different species, the most well-studied and the best known being Cyclotella meneghiniana. Despite being among the most dominant genera in low-productivity environments, it is relatively understudied.
Diatoms belong to a large group called the heterokonts, which include both autotrophs such as golden algae and kelp; and heterotrophs such as water moulds. The classification of heterokonts is still unsettled: they may be designated a division, phylum, kingdom, or something intermediate to those. Consequently, diatoms are ranked anywhere from a class, usually called Diatomophyceae or Bacillariophyceae, to a division (=phylum), usually called Bacillariophyta, with corresponding changes in the ranks of their subgroups.
 | This diatom article is a stub. You can help Wikipedia by expanding it. |