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''Geastrum triplex'' is an inedible fungus which is found in the detritus and leaf litter of hardwood forests in many parts of the world. It is commonly known as the collared earthstar, the saucered earthstar, or the triple earthstar—and less commonly by the alternative species name ''Geastrum indicum''. It is the largest member of the genus ''Geastrum'' (or earthstar fungi) and expanded mature specimens can reach a tip-to-tip length of up to . Immature fruit bodies are spherical—somewhat resembling puffballs with pointed beaks—and are partially or completely buried in the ground. As the fungus matures, the outer layer of tissue (the exoperidium) splits into four to eight pointed segments that spread outwards and downwards, lifting and exposing the spherical inner spore sac. The spore sac contains the gleba, a mass of spores and fertile mycelial tissue that when young is white and firm, but ages to become brown and powdery. Often, a layer of the exoperidium splits around the perimeter of the spore sac so that it appears to rest in a collar or saucer. Atop the spore sac is a small pointed beak, the peristome, which has a small hole from which spores may be released. The species is widespread and can be found in Asia, Australasia, Europe, and both North and South America. The fungus has a history of use in the traditional medicines of native North America and China. Fruit bodies have been analyzed chemically to determine their lipid content, and various chemical derivatives of the fungal sterol ergosterol have been identified. ==Taxonomy and classification== The species was first described scientifically, by German botanist Franz Wilhelm Junghuhn, as ''Geaster triplex'' in 1840. The earlier genus name ''Geaster'', introduced by Italian botanist Pier Antonio Micheli in 1727 in ''Nova Plantarum Genera'', is considered an orthographical variant of ''Geastrum''.〔 Junghuhn, who was living in Indonesia and extensively surveyed its fungal flora, discovered the type specimen on Mount Panggerangi on the island Java, at an elevation between . Today, the type specimen is kept at the National Herbarium of the Netherlands in Leiden.〔 The morphological feature used by Junghuhn to differentiate ''G. triplex'' from other similar earthstars was the collar-like structure of the inner layer of the exoperidium.〔 American mycologist Curtis Gates Lloyd would later erroneously suggest that the species was a "giant form" of ''Geastrum saccatum''.〔 Several authors have regarded ''Geastrum indicum'' as the correct name for ''G. triplex''.〔 This is because ''G. indicum''—a species described by Johann Friedrich Klotzsch in 1832 as ''Cycloderma indicum''〔 and then moved to Geastrum by Stephan Rauschert in 1959〔〔—may be the same species as ''Geastrum triplex''. If it is in fact the same species, the first published name (i.e., ''G. indicum'') has nomenclatorial priority according to the rules of the International Code of Botanical Nomenclature. More recently, several authors argue that ''G. indicum'' should be rejected as a ''nomen dubium'' and ''G. triplex'' maintained as the correct name for the species.〔〔〔〔 Stellan Sunhede's 1989 monograph of European species of ''Geastrum'' follows V. J. Staněk's concept〔 for the infrageneric (below the level of genus) placement of ''Geastrum'', and places ''G. triplex'' with species that do not incorporate and encrust forest debris (section Basimyceliata). ''G. triplex'' is further categorized in subsection Laevistomata, which includes species with a fibrillose peristome—that is, made of parallel, thin, thread-like filaments. Within subsection Laevistomata it is in stirps Triplex, due to its delimited (with a distinct restricting edge) or irregularly torn peristome.〔 The specific epithet ''triplex'' means "threefold", and refers to the three-layered peridium.〔 ''Geastrum triplex'' has acquired several vernacular names, including the collared earthstar,〔〔 the saucered earthstar,〔 and the triple earthstar.〔 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「Geastrum triplex」の詳細全文を読む スポンサード リンク
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