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''Aphanoascus fulvescens'' is a mould fungus that behaves as a keratinophilic saprotroph and belongs to the Ascomycota. It is readily isolated from soil and dung containing keratin-rich tissues that have been separated from their animal hosts. This organism, distributed worldwide, is most commonly found in areas of temperate climate, in keeping with its optimal growth temperature of . While ''A. fulvescens'' is recognized as a geophilic fungal species, it is also a facultative opportunistic pathogen. Although it is not a dermatophyte, ''A. fulvescens'' has occasionally been shown to cause onychomycosis infections in humans. Its recognition in the laboratory is clinically important for correct diagnosis and treatment of human dermal infections. ==Taxonomy== ''Aphanoascus fulvescens'' has faced many discrepancies and challenges for proper taxonomic placement. The naming and classification of ''A. fulvescens'' has been subject to taxonomic confusion since the original discovery of the species.〔Cano J, Guarro J. (April 1990). “The genus ''Aphanoascus''”. ''Mycological Research'' 94: 355–377〕 The genus ''Aphanoascus'', to which ''A. fulvescens'' belongs, was first described in 1890 by Hugo Zukal after isolating it from alligator dung in Vienna.〔〔Rippon JW, Lee FC, McMillen S. (1970). “Dermatophyte infection caused by ''Aphanoascus fulvescens''”. ''Archives of Dermatology'' 102(5):552-&. doi:10.1001/archderm.102.5.552〕 Zukal named this fungus ''Aphanoascus cinnabarinus''. The same fungus however, had already been isolated earlier in 1875 under the name ''Badhamia fulvescens'' by Cooke. The genus ''Aphanoascus'' was then further reviewed by Apinis in 1968 who deemed ''A. fulvescens'' as the type species. While most mycologists accept this title, others argue that ''Aphanoascus'' is a synonym for ''Anixiopsis'', which was the genus name given to a soil isolate described by Hansen as ''Anixiopsis fulvescens''. Later in 1973, further confusion was caused with the introduction of ''Aphanoascus cinnabarinus'' as the new type species for the genus ''Aphanoascus'' by Udagawa & Takada. In 1980, Benny & Kimbrough recognized ''Aphanoascus'' and ''Anixiopsis'' as two distinct genera, the former distinguished by reticulate ascospores and the latter by ridged ascospores. Whether the two genera are synonymous remains controversial; many authors continue to accept them as one genus.〔〔Jong SC, Davis EE (1975). “The imperfect state of ''Aphanoascus''”. ''Mycologia'' 67:1143–7〕 Initially, ''A. fulvescens'' was placed in the family Cephalothecaceae by Apinis, in the Onygenaceae by Malloch & Cain and Currah, in Trichocomaceae by Benny & Kimbrough, and in Amauroascaceae by Arx.〔 Today, most mycologists accept ''A. fulvescens'' as the type species of the genus ''Aphanoascus'' under the family Onygenaceae.〔 ''A. fulvescens'' refers to the sexual state, or teleomorph, of the organism. ''Chrysosporium keratinophilum'' is regarded by some mycologists as the asexual state, or anamorph,〔“Synonym and Classification Data for ''Aphanoascus'' spp.” ''Doctor Fungus''. 2007. Retrieved on 11/02/13. http://www.doctorfungus.org/imageban/synonyms/aphanoascus.php〕 however others argue that this is only the asexual state of ''Aphanoascus keratinophilus''.〔Campbell, C. K., Johnson, E. M. and Warnock, D. W. (2013) "Miscellaneous Moulds".''Identification of Pathogenic Fungi Second Edition''. Wiley-Blackwell. Oxford, UK. ISBN 9781444330700〕 ''Aphanoascus fulvescens'', ''Aphanoascus terreus'', ''Aphanoascus canadensis'', ''Aphanoascus reticulisporus'', and ''Keratinophyton durum'' or ''Anixiopsis biplanata'' are the species that are currently accepted under the genus ''Aphanoascus''.〔 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「Aphanoascus fulvescens」の詳細全文を読む スポンサード リンク
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