Fungalpedia – Note 666, Pseudomicrothyrium
Pseudomicrothyrium X.Y. Zeng, Hongsanan & K.D. Hyde
Citation when using this data: D. S. Marasinghe et al. 2023 (in prep.) – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank.
Classification: Microthyriaceae, Microthyriales, Dothideomycetidae, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Saprobic and epiphytic on dead leaves. Superficial hyphae superficial, pale brown, septate, branched, loosely reticulate. Sexual morph: Thyriothecia superficial, solitary or gregarious, orbicular, dark brown to light brown, ostiolate, with a colourless basal layer, connected with hyphae, easily detached from the host surface. Upper wall light brown, comprising cells of radial arrangement of textura prismatica, darken at the central ostiole, tapering at margin. Hamathecium comprising asci inclined from the base and rim towards the central ostiole, with thin, filiform, narrow cellular pseudoparaphyses. Asci 8-spored, bitunicate, fissitunicate, ovoid to obpyriform. Ascospores 2–3-seriate, fusiform to ellipsoidal, hyaline, 1-septum, upper cell slightly wider than lower cell, not constricted at the septum, with 2–4 apical append- ages, usually with 2 large guttules in the upper cell, 2 small guttules in the lower cell, smooth-walled. Asexual morph: Undetermined (Hongsanan et al. 2020a).
Notes: Hongsanan et al. (2020a) introduced Pseudomicrothyrium with the type species P. thailandicum. This genus is morphologically similar to Microthyrium in having orbicular, superficial, thyriothecia with ostiole surrounded by a ring with dark cells. However, it differs from Microthyrium by distinct superficial, hyaline to pale brown, reticulate hyphae, thyriothecia with fibrous margin and guttulate ascospores with 2–4 apical appendages (Hongsanan et al. 2020a).
Type species: Pseudomicrothyrium thailandicum X.Y. Zeng, S. Hongsanan & K.D. Hyde, Fungal Diversity [79] (2020).
Other accepted species: Species Fungorum – search Pseudomicrothyrium.
References
Entry by
Diana Sandamali Marasinghe, 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, Mushroom Research Foundation, 128 M.3 Ban Pa Deng T. Pa Pae, A. Mae Taeng, Chiang Mai, 50150, Thailand
Published online 29 August 2023