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Telonemia is a phylum of microscopic eukaryote, single-celled organisms.〔http://www.apollon.uio.no/vis/art/2006_4/Artikler/telonemia_english〕 They were formerly classified as protists until that kingdom fell out of general use, and are suggested to have evolutionary significance in being a possible transitional form between ecologically important heterotrophic and photosynthetic species among chromalveolates.〔http://www.cees.no/component/option,com_seminar/id,98〕 One paper places them in the SAR supergroup. Phylogenomic analyses of 127 genes place Telonemia with Centroheliozoa in a group also consisting of cryptomonads and haptophytes (see Cryptomonads-haptophytes assemblage). Although they have been studied in primarily marine environments, they have also been found in freshwater.〔 〕〔 〕 Telonemia: a new phylum related to the kingdom Chromista. It was recently discovered by Shalchian-Tabrizi et al. () that the 18S rDNA sequences formed two major groups, Group 1 and 2, including T. subtilis and T. antarcticum respectively, and that these were further sub-divided into several statistically supported clades of sequences with restricted geographic distribution. Species of Telonemia are heterotrophic predators, feeding on a wide range of bacteria and pico- to nano-sized phytoplankton. By using specific PCR primers we reveal a much larger diversity of Telonemia from environmental samples than previously uncovered by eukaryote-wide primers. They are globally distributed in marine waters and are frequently encountered in environmental clone libraries. The evolutionary origin of Telonema was inferred from phylogenetic reconstruction of single- and concatenated sequences obtained from both cultured strains and environmental clones (SSU only). ==Species== Although only two species have been described formally, DNA sequences collected from seawater suggest there are many more species which have not yet been described. * ''Telonema antarctica'' Thomsen 1992 * ''Telonema subtile'' Griessmann 1913 (synonym ''Telonema subtilis'' Griessmann, 1913)〔 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Telonemia」の詳細全文を読む スポンサード リンク
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