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Taxonomy Of Diatoms
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. Genera and species An estimated 20,000 extant diatom species are believed to exist, of which around 12,000 have been named to date according to Guiry, 2012 (other sources give a wider range of estimatesCanter-Lund, H. and Lund, J.W.G. (1995). ''Freshwater Algae: Their microscopic world explained'', Biopress Limited. .). Around 1,000-1,300 diatom genera have been described, both extant and fossil, of which some 250-300 exist only as fossils. Classes and orders Overvie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fragilariophyceae
Fragilariophyceae is a group of pennate diatoms lacking a raphe. Examples It includes the following genera: Fragilariales *'' Ardissonea'' *''Asterionella'' *''Asterionellopsis'' *'' Catacombas'' *'' Diatoma'' *''Fragilaria'' *'' Fragilariforma'' *'' Grammonema'' *'' Hyalosynedra'' *'' Neofragilaria'' *'' Opephora'' *'' Pseudostaurosira'' *'' Punctastriata'' *'' Staurosira'' *'' Staurosirella'' *'' Synedra'' *'' Synedropsis'' *'' Tabularia'' *'' Ulnaria'' Striatellales *'' Hyalosira'' *'' Striatella'' *'' Toxarium'' Other *''Climacosphenia'' *'' Cyclophora'' *'' Delphineis'' *'' Protoraphis'' *'' Rhabdonema'' *'' Rhaphoneis'' *'' Tabellaria'' *''Thalassionema ''Thalassionema'' is a genus of Chromista belonging to the family Thalassionemataceae. The genus was described in 1902 by Albert Grunow, Grunow ex Mereschkowsky. Species: * ''Thalassionema nitzschioides'' Grunow, 1862 References Fragi ...'' References Heterokont classes {{Diatom-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaetocerotales
Chaetocerotales is an order of diatoms belonging to the class Mediophyceae. Families: * Acanthocerataceae * Attheyaceae * Chaetocerotaceae References {{Taxonbar, from=Q2947529 Diatoms Diatom orders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triceratiales
Triceratiales is an order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of ... of diatoms. References Coscinodiscophyceae Diatom orders {{Diatom-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biddulphiales
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 (or valves or frustules) 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. In terms of cell cycle, vegetative cells are diploid and undergo mitosis during normal cell division. In sexual species, oogamous meiosis produces haploid gametes, either ova or sperm cells. These fuse to produce a zygote A zygote (, ) is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontella Aurita Cells
''Odontella'' is a genus of marine diatoms.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). ''Identifying Marine Phytoplankton'', Academic Press. It contains the following species: * ''Odontella aurita'' (Lyngbye) C. A. Agardh * ''Odontella calamus'' (Brun & Tempère) H. J. Schrader * ''Odontella cornuta'' (J. Brun) H. J. Schrader * ''Odontella granulata'' (Roper) R. Ross * ''Odontella hastata'' (Greville) J. Fenner ex D. M. Williams * ''Odontella litigiosa'' (Van Heurck) Hoban * ''Odontella longicruris'' (Greville) Hoban * ''Odontella mobiliensis'' (J. W. Bailey) Grunow * ''Odontella regia'' (Schultze) Simonsen * ''Odontella rhombus'' * ''Odontella septentrionalis'' H. J. Schrader * ''Odontella sinensis'' (Greville) Grunow * ''Odontella weissflogii ''Odontella'' is a genus of marine diatoms.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom - Isthmia Nervosa - 400x (16237138292)
A diatom (Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising several genera 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 (800 m) 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 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attheya
''Attheya'' is a genus 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.Crawford, R.M., Hinz, F. and Koschinski, P. 2000. The combination of ''Chaetoceros gaussii'' (Bacillariophyta) with ''Attheya''. Phycologia 39(3):238-244. Description They are distinguished morphologically from ''Chaetoceros'' by the structure of valve outgrowths or girdle bands. The girdle bands can only be seen with an electron microscope.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus ''Attheya''. I. A description of four new taxa, and the transfer of ''Gonioceros septentrionalis'' and ''G. armatus''. ''Diatom research''. 9:27-51. Resting spores are seldom observed. Vegetative cells tend to attach to different substrates, including other diatoms,Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
