Fungalpedia – Note 1025, Phialophora

 

Phialophora. Medlar.

Citation when using this data: Tian Q et al. 2021 (in prep.) – Fungalpedia, Ascomycota.

Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig 1

Classification: Herpotrichiellaceae, Chaetothyriales, Chaetothyriomycetidae, Eurotiomycetes, Pezizomycotina, Ascomycota, Fungi

Saprobic on decaying wood or pathogenic or animals, including humans. Mycelium superficial or partly immersed, comprising cylindrical, brown, septate hyphae in rope-like strands, tending to become moniliform, smooth-walled. Sexual morph: Capronia-like. Ascomata perithecioid, arising singly, dispersed, superficial, immersed only at the base when mature, subglobose, black, smooth-walled but with aseptate or 1-multi-septate unbranched, dark brown setae, arising from the upper part, ostiolate. Setae smooth-walled, rounded at the apex and hardly attenuated or tapering to the ends. Ostioles lateral, black, flattened. Peridium thick, composed of multi-layered, hyaline to brown cells of textura angularis. Hamathecium gelatinized, lacking pseudoparaphyses. Asci 8-spored or multi-spored, bitunicate, obpyriform to broadly clavate, wall apically thickened, J–. Ascospores overlapping, irregularly biseriate, oval to fusiform, muriform, hyaline to yellow-brown or grey, 1–7-trans-septate, constricted at the septa, with or without longitudinial septa, some slightly curved, smooth-walled, with or without guttules, without a gelatinous sheath or appendages. Asexual morph: hyphomycetous. Conidiophores mononematous, macronematous, unbranched, erect, hyaline to brown, straight or flexuous, cylindrical, smooth. Conidiogenous cells enteroblastic, phialidic, terminally or laterally, branched, cylindrical- elongate or occasionally flask-shaped, hyaline to brown, in a globose, gelatinous mass. Collarettes conspicuous, narrowly cylindrical to funnel-shaped or slightly flaring. Conidia acrogenous, obovoidal, clavate, ellipsoidal or fusiform, and adhere in chains, hyaline to sunhyaline, aseptate or 1-septate, sticky, smooth-walled. Conidial secession schizolytic (Medlar 1915, Schol-Schwarz 1970). 

Type material – not indicated, from a skin lesion of Homo sapiens. 

Notes – The black yeast genus Phialophora was introduced with P. verrucosa as the type species (Medlar 1915) which is a human skin pathogen causing chromoblastomycosis. The genus is characterized by a melanized thallus and subhyaline, obovoidal, clavate, ellipsoidal or fusiform one-celled, sticky conidia, that adhere in chains or slimy heads, that are produced through subhyaline to lightly pigmented, cylindrical- elongate or occasionally flask-shaped phialides with narrowly cylindrical to funnel-shaped or slightly flaring collarettes in a poorly differentiated conidial apparatus (Medlar 1915, Schol-Schwarz 1970). These species occur commonly as saprobes or plant pathogens on decaying wood (Untereiner & Naveau 1999, Untereiner et al. 2008, Zhuang et al. 2010, Crous et al. 2012), and have been isolated from soil, water and food (apples, butter, margarine) (Gezuele et al. 1972, Untereiner & Naveau 1999, Untereiner et al. 2008). Phialophora species also cause chromoblastomycosis, disseminated phaeohyphomycosis and mycetoma or other skin infections of humans (de Hoog et al. 2000a, b, Caretta et al. 2006, Untereiner et al. 2008, Al-Tawfiq & Amr 2009, Feng et al. 2012, Morio et al. 2012, Li et al. 2017). Species of the sexual genus Capronia Sacc. are linked to Phialophora and several hyphomycetous asexual morphs and yeast-like synanamorphs in culture ((Untereiner & Naveau 1999, Untereiner et al. 2008, de Hoog et al. 2011, Réblová et al. 2013).

Type species: Phialophora verrucosa  Medlar, Mycologia 7(4): 203 (1915).

Other accepted species: Species Fungorum – search Phialophora.

 

image

 

Figure 1 – Phialophora verrucosa   (a, b CBS 281.35, c, e dried culture of Conant 204 (FH), d. f type material (FH), redrawn from Schol-Schwarz 1970). a Proliferating conidiophore with conidia. b Chlamydospore with muzzle-like protuberance. c Anastomosis of chlamydospores. d Chlamydospores. e Conidia. f Moniliform hypha with terminal phialide. Scale bars: a–c, e, f = 10 μm, d = 5 μm.

 

References

Al–Tawfiq JA, Amr SS. 2009 – Madura leg due to Exophiala jeanselmei successfully treated with surgery and itraconazole therapy. Medical Mycology 47, 648–652.

Caretta G, Tosi S, Piontelli E, de Hoog GS. 2006 – Phialophora sessilis, a lithobiont fungus. Mycotaxon 95, 281–284.

Crous PW, Summerell BA, Shivas RG, Burgess TI et al. 2012 – Fungal Planet description sheets: 107–127. Persoonia 28, 138–182.

de Hoog GS, Guarro J, Gené J, Figueras MJ. 2000a – Atlas of Clinical Fungi, 2nd ed. Centraalbureau voor Schimmelcultures, Utrecht, Universitat Rovira i Virgili, Reus.

de Hoog GS, Mayser P, Haase G, Horré R et al. 2000b – A new species, Phialophora europaea, causing superficial infections in humans. Mycoses 43, 409–416.

de Hoog GS, Vicente VA, Najafzadeh M, Harrak M et al. 2011 – Waterborne Exophiala species causing disease in cold-blooded animals. Persoonia 27, 46–72.

Feng P, Lu Q, Najafzadeh MJ, van den Ende AG et al. 2012 – Cyphellophora and its relatives in Phialophora: biodiversity and possible role in human infection. Fungal Diversity 65, 17–45.

Gezuele E, Mackinnon JE, Conti-Diaz IA. 1972 – The frequent isolation of Phialophora verrucosa and Fonsecaea pedrosoi from natural sources. Sabouraudia 10, 266–273.

Medlar EM. 1915 – A new fungus, Phialophora verrucosa, pathogenic for man. Mycologia 7(4), 200–203.

Morio F, Le Berre JY, Garcia-Hermoso D, Najafzadeh MJ et al. 2012 – Phaeohyphomycosis due to Exophiala xenobiotica as a cause of fungal arthritis in an HIV-infected patient. Medical Mycology 50, 513–517.

Réblová M, Untereiner WA, Réblová K. 2013 – Novel evolutionary lineages revealed in the Chaetothyriales (Fungi) based on multigene phylogenetic analyses and comparison of ITS secondary structure. PLoS ONE 8(5), e63547.

Untereiner WA, Angus A, Réblová M, Orr MJ 2008 – Systematics of the Phialophora verrucosa complex: new insights from analyses of β–tubulin, large subunit nuclear rDNA and ITS sequences. This paper is one of a selection of papers published in the Special Issue on Systematics Research. Botany 86, 742–750.

Untereiner WA, Naveau FA. 1999 – Molecular systematics of the Herpotrichiellaceae with an assessment of the phylogenetic positions of Exophiala dermatitidis and Phialophora americana. Mycologia 91, 67–83.

Zhuang JL, Zhu MQ, Zhang R, Yin H et al. 2010 – Phialophora sessilis, a species causing flyspeck signs on bamboo in China. Mycotaxon 113, 405–413.

 

Entry by

Qing Tian, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand, School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand

 

Published online 16 December 2021

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