Cystofilobasidiales » Mrakiaceae


Itersonilia Derx, in Bulletin du Jardin Botanique de Buitenzorg 17: 471 (1948)

Diagnosis: Basidiocarps absent. Dikaryotic hyphae occasionally produced, regularly branched, inflated cells may be present. Monokaryotic hyphae may be present. Clamp connections present. Septa with dolipores lacking parenthesomes. Pseudohyphae without clamp connections occasionally present. Sexual reproduction not observed. Budding (monokaryotic) cells may be present. Ballistoconidia present. Chlamydospores occasionally produced. Fermentation absent. Low-weight aromatic compounds not utilised. Nitrate and nitrite utilised. Starch-like compounds may be produced. The major CoQ system CoQ-9 or CoQ-10.

Index Fungorum number: IF8644

Type species: Itersonilia perplexans Derx., in Bulletin du Jardin Botanique de Buitenzorg 17: 471 (1948)

Notes: The species Udeniomyces pannonicus was separated from the Udeniomyces clade and located together with Itersonilia perplexans based on molecular data (Niwata et al., 2002, Boekhout et al., 2011, Weiss et al., 2014, Liu et al., 2015a). I. perplexans and U. pannonicus are phenotypically similar by forming grayish to yellowish colonies, whereas the other Udeniomyces species form pinkish-white to orange-white colonies. The emended genus Itersonilia contained two species and an additional sequence representing a potential new species was obtained from public databases.



Itersonilia diksonensis A.V. Kachalkin 2019

Itersonilia pannonica (Niwata, Tornai-Leh., T. Deák & Nakase) Xin Zhan Liu, F.Y. Bai, M. Groenew. & Boekhout 2015

Itersonilia pastinacae Channon 1963

Itersonilia perplexans Derx 1948


Figure 1. Phylogenetic relationships of yeasts and related taxa from the order Cystofilobasidiales in Tremellomycetes obtained by maximum-likelihood analysis of LSU (D1/D2 domains) rRNA gene. Tree topology was backbone-constrained with the well-supported (>85 %) bipartitions of the topology of the seven-genes tree. Bootstrap percentages (BP) of maximum likelihood and neighbour-joining analyses from 1 000 replicates are shown respectively from left to right on the deep and major branches resolved and in brackets following recognised clades. The type species of accepted genera are in bold and the taxa not included in the seven-genes dataset are in red. Note: ns, not supported (BP < 50 %).



Boekhout, T., Fonseca, A., Sampaio, J. P., Bandoni, R. J., Fell, J. W., & Kwon-Chung, K. J. (2011). Discussion of teleomorphic and anamorphic basidiomycetous yeasts. In The Yeasts (pp. 1339-1372). Elsevier.

Liu, X. Z., Wang, Q. M., Theelen, B., Groenewald, M., Bai, F. Y., & Boekhout, T. (2015a). Phylogeny of tremellomycetous yeasts and related dimorphic and filamentous basidiomycetes reconstructed from multiple gene sequence analyses. Studies in mycology, 81, 1-26.

Liu, X. Z; Wang, Q. M; Göker, M; Groenewald, M; Kachalkin, A.V; Lumbsch, H.T; Millanes, A.M; Wedin, M; Yurkov,A.M; Boekhout,T; Bai, F.-Y. (2015b). Towards an integrated phylogenetic classification of the Tremellomycetes. Studies in Mycology. 81:85-147

Niwata, Y., Takashima, M., Tornai-Lehoczki, J., Deak, T., & Nakase, T. (2002). Udeniomyces pannonicus sp. nov., a ballistoconidium-forming yeast isolated from leaves of plants in Hungary. International journal of systematic and evolutionary microbiology, 52(5), 1887-1892.

Weiss, M., Bauer, R., Sampaio, J. P., & Oberwinkler, F. (2014). 12 Tremellomycetes and Related Groups. In Systematics and Evolution (pp. 331-355). Springer, Berlin, Heidelberg.


About Basidiomycota

The webpage Basidiomycota provides an up-to-date classification and account of all genera of the phylum Basidiomycota.


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