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''Charnia'' is the genus name given to a frond-like Ediacaran lifeform with segmented, leaf-like ridges branching alternately to the right and left from a zig-zag medial suture (thus exhibiting glide reflection, or opposite isometry). The genus ''Charnia'' was named after Charnwood Forest in Leicestershire, England, where the first fossilised specimen was found. The living organism was a type of fractal life form that grew on the sea floor and is believed to have fed on nutrients in the water. Despite ''Charnias fern-like appearance, it is not a plant or alga because the nature of the fossilbeds where specimens have been found demonstrate that it originally lived in deep water, well below the photic zone where photosynthesis can occur. == Diversity == Several ''Charnia'' species were described but only the type species ''C. masoni'' is considered valid. Some specimens of ''C. masoni'' were described as members of genus ''Rangea'' or a separate genus ''Glaessnerina'': * ''Rangea grandis'' Glaessner et Wade, 1966 = ''Glaessnerina grandis'' * ''Rangea sibirica'' Sokolov, 1972 = ''Glaessnerina sibirica'' Two other described ''Charnia'' species have been transferred to two separate genera * ''Charnia wardi'' Narbonne et Gehling, 2003 transferred to the genus ''Trepassia'' Narbonne et al., 2009 * ''Charnia antecedens'' Laflamme et al., 2007 transferred to the genus ''Vinlandia'' Brasier, Antcliffe et Liu, 2012 A number of Ediacaran form taxa are thought to represent ''Charnia'' (or ''Charniodiscus'') at varying levels of decay; these include the Ivesheadiomorphs ''Ivesheadia'', ''Blackbrookia'', ''Pseudovendia'' and ''Shepshedia''. 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「Charnia」の詳細全文を読む スポンサード リンク
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