Thyridiaceae J.Z. Yue & O.E. Erikss., Syst. Ascom. 6(2): 233 (1987)
MycoBank number: MB 82030; Index Fungorum number: IF 82030; Facesoffungi number: FoF 01913; 35 species.
Hemibiotrophic or saprobic on woody substrates. Sexual morph: Ascomata stromatic. Stromatal tissue immersed, becoming erumpent to superficial, soft-textured, reddish brown to brightly pigmented. Ascomata immersed in stromata, globose, ostiolate. Ostioles periphysate, with short or long papilla or necks, sometimes convergent necks merging into one ostiole. Peridium composed of compressed rows of cells, externally brown, internally hyaline. Paraphyses filamentous, septate. Asci 8-spored, unitunicate, oblong cylindric, apical ring J-. Ascospores uniseriate, shades of brown, ellipsoid or biconoid, symmetric, 1-septate or muriform. Asexual morph: Coelomycetous or hyphomycetous, often developing on the edge of sexual morph stroma. Conidiomata immersed in stromata, irregular, multilocular and folded inside. Conidiogenous cells emerging from the interior of the cavity, bearing one or more conidiogenous cells. Conidiogenous cells enteroblastic, phialidic, hyaline. Conidia ellipsoidal, aseptate, small, hyaline. Holoblastic sympodial conidia also produced from hyphae. Sometimes ascospores produce primary conidia (adapted from Barr 1990b, Leuchtmann & Müller 1986, Maharachchikumbura et al. 2016b).
Type genus – Thyridium Nitschke
Notes – In a phylogenetic and molecular clock analyses, Thyridiaceae showed a close relationship to Annulatascales and Myrmecridiales (Hyde et al. 2017a, Hongsanan et al. 2017, Senanayake et al. 2017a). However, only a single strain of the type genus has sequence data (Thyridium vestitum strain AFTOL-ID 172), and the ordinal placement remains uncertain in Diaporthomycetidae (Maharachchikumbura et al. 2015b, 2016b, Hongsanan et al. 2017). Maharachchikumbura et al. (2015, 2016b) and Wijayawardene et al. (2018a) accepted three genera in Thyridiaceae (Mattirolia, Pleurocytospora, and Thyridium). No sequence data are available for Pleurocytospora species. Mattirolia has been synonymised under Thyronectria (Nectriaceae) by Jaklitsch & Voglmayr (2014) based on an ex-epitype sequence of the generic type of Mattirolia, M. roseovirens. Here we follow the treatment of Jaklitsch & Voglmayr (2014).