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The Fungi imperfecti or imperfect fungi, also known as Deuteromycota, are fungi which do not fit into the commonly established taxonomic classifications of fungi that are based on biological species concepts or morphological characteristics of sexual structures because their sexual form of reproduction has never been observed; hence the name "imperfect fungi." Only their asexual form of reproduction is known, meaning that this group of fungi produces their spores asexually, in the process called sporogenesis. The ''Deuteromycota'' (Greek for "second fungi") were once considered a formal phylum of the kingdom Fungi. The term is now used only informally, to denote species of fungi that are asexually reproducing members of the fungal phyla Ascomycota and Basidiomycota. There are about 25,000 species that have been classified in the deuteromycota and many are basidiomycota or ascomycota anamorphs. Fungi producing the antibiotic penicillin and those that cause athlete's foot and yeast infections are imperfect fungi. In addition, there are a number of edible imperfect fungi, including the ones that provide the distinctive characteristics of Roquefort and Camembert cheese. Other, more informal, names besides Deuteromycota ("Deuteromycetes") and fungi imperfecti, are anamorphic fungi, or mitosporic fungi, but these are terms without taxonomic rank. ==Problems in taxonomic classification== Although Fungi imperfecti/Deuteromycota is no longer formally accepted as a taxon, many of the fungi it included have yet to find a place in modern fungal classification. This is because most fungi are classified based on characteristics of the fruiting bodies and spores produced during sexual reproduction, and members of the Deutromycota have only been observed to produce asexual or no spores. Mycologists are unique among those who study extant organisms in using a dual system of nomenclature. Dual naming was permitted by Article 59 of the International Code of Botanical Nomenclature (which governs the naming of plants and fungi); however, this was abolished in the 2011 update of the Code.〔http://www.iapt-taxon.org/nomen/main.php?page=art59〕 Under the former system, a name for an asexually reproducing fungus was considered a ''form taxon''. For example, the ubiquitous and industrially important mold, ''Aspergillus niger'', has no known sexual cycle. Thus ''Aspergillus niger'' is considered a form taxon. In contrast, isolates of its close relative, ''Aspergillus nidulans'', revealed it to be the anomorphic stage of a teleomorph (the ascocarp or fruiting body of the sexual reproductive stage of a fungus, which was already named ''Emericella nidulans''. When such a teleomorphic stage is known, that name will take priority over the name of an anamorph (which lacks a sexual reproductive stage). Hence the formerly classified ''Aspergillus'' species is now properly called ''Emericella nidulans''. 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「Fungi imperfecti」の詳細全文を読む スポンサード リンク
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