Knufia

Fungalpedia – Note 1041, Knufia

 

Knufia L.J. Hutchison & Unter

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

Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig 1

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

Pathogenic on humans or saprobic on leaves and insects, lichenicolous, rock-inhabiting in terrestrial habitats. Sexual morph: Undetermined. Asexual morph: hyphomycetous. Colonies in axenic culture black, slow-growing. Hyphae cylindrical to moniliform, subhyaline to brown, septate, smooth-walled. Conidiogenous cells holoblastic, terminal or lateral, produced on undifferentiated hyphae. Conidia obovate to cylindrical, subhyaline to brown, aseptate to multiseptate. Phialides obclavate. Phialoconidia cylindrical to pyriform, hyaline, aseptate.

Notes: The black-yeast genus Knufia L.J. Hutchison & Unter. was introduced by Hutchison & Untereiner (1995) to accommodate K. cryptophialidica L.J. Hutchison & Unter. The diagnostic features of Knufia are that have the black, slow-growing colonies and undifferentiated, holoblastic, conidiogenous cells on the hyphae. Darkly pigmented, enlarged multicellular bodies are reliable characteristics to differentiate species, as well as the phialides (Hutchison & Untereiner 1995, Tsuneda et al. 2004, 2005, 2011, Sun et al. 2020). Only the ex-type species has phialidic conidia. Knufia peltigerae (Fuckel) Réblová & Unter. and K. perfecta Mehrabi, Asgari & Hemmati, are the sexual morph species of this genus (Untereiner et al. 2011, Réblová et al. 2013, Mehrabi et al. 2018) with superficial, dark, setose ascomata, bitunicate, sessile asci and hyaline, septate, ellipsoidal to fusiform ascospores (Untereiner et al. 2011, Mehrabi et al. 2018). Tsuneda & Currah (2005) suggested discontinuing the characters of phialidic conidia in the genus. Knufia are black-yeasts in Trichomeriaceae. Some allied species, are congeneric and have been transferred to Knufia because of their close phylogenetic relationships (Hawksworth et al. 1987, Tsuneda et al. 2011, Réblová et al. 2013, He et al. 2013, Crous et al. 2019b, Sun et al. 2020) shown based on multigenes phylogenetic analyses.

Type species: Knufia cryptophialidica L.J. Hutchison & Unter., Mycologia 87(6): 903 (1996) [1995].

Other accepted species: Species Fungorum – search Knufia.

 

 

Figure 1 – Knufia cryptophialidica (redrawn from Hutchison et al. 1995). a Conidia. b Phialides and phialoconidia from MEA (DAOM 216555). c Conidiogenous cells on MLA (DAOM 216555). d Conidiogenous cells on MEA (DAOM 216554). Scale bars: a–d = 10 µm.

 

References

Crous PW, Schumacher RK, Akulov A, Thangavel R et al. 2019b – New and interesting fungi 2. Fungal Systematics and Evolution 3, 57–134.

Hawksworth DL, Eriksson O. 1987 – Notes on ascomycete systematics. Nos 225–463. Systema Ascomycetum 6, 111–165.

He F, Lin B, Sun JZ, Liu XZ. 2013 – Knufia aspidiotus sp. nov., a new black yeast from scale insects. Phytotaxa 153(1), 39–50.

Hutchison LJ, Untereiner WA, Hiratsuka Y. 1995 – Knufia cryptophialidica gen. et sp. nov., a dematiaceous hyphomycete isolated from black galls of trembling aspen (Populus tremuloides). Mycologia 87(6), 902–908.

Mehrabi M, Asgari B, Hemmati R. 2018 – Knufia perfecta, a new black yeast from Iran, and a key to Knufia species. Nova Hedwigia 106(3–4), 519–534.

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.

Sun W, Su L, Yang S, Sun J et al. 2020 – Unveiling the Hidden Diversity of Rock-Inhabiting Fungi: Chaetothyriales from China. Journal of Fungi 6(4, no. 187), 1–37.

Tsuneda A, Currah RS. 2004 – Knufia endospora, a new dematiaceous hyphomycete from trembling aspen. Reports of the Tottori Mycological Institute 42, 1–9. 

Tsuneda A, Currah RS. 2005 – Pleomorphic conidiogenesis among strains of Knufia cryptophialidica. Canadian Journal of Botany-revue Canadienne De Botanique 83(5), 510– 517. 

Tsuneda A, Hambleton S, Currah RS. 2011 – The anamorph genus Knufia and its phylogenetically allied species in Coniosporium, Sarcinomyces, and Phaeococcomyces. Botany 89(8), 523– 536.

Untereiner WA, Gueidan C, Orr MJ, Diederich P. 2011 – The phylogenetic position of the lichenicolous ascomycete Capronia peltigerae. Fungal Diversity 49, 225–233.

 

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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