Oxydothidaceae S. Konta & K.D. Hyde, Mycosphere 7(9): 1431 (2016)

MycoBank number: MB 552561; Index Fungorum number: IF 552561; Facesoffungi number: FoF 02700; 79 species.

Saprobic, endophytic or parasitic on monocotyledons. Sexual morph: Ascomata solitary or irregularly scattered, ellipsoidal or subglobose, immersed or semi-immersed, slightly raised from host surface with light or darkened discs, with most taxa lying horizontal to the host surface. Peridium thick-walled, brown to dark brown, and/or peridium cells merging with the host tissue. Paraphyses hypha-like, filamentous, irregular, septate, persisting between asci, but often fragmenting in dried material. Asci 8-spored, unitunicate, cylindrical, pedicellate, with a J+ (rarely J-), subapical ring. Ascospores fasciculate, hyaline, sometimes appearing yellow in mass, fusiform or filiform, 1-septate, tapering from the center to spine-like, pointed or rounded ends. Appressoria produced by germinating ascospores in some species, solitary, hyaline or greenish, or pale brown to brown, irregular in shape, thick-walled. Asexual morph: Hyphomycetous. Selenosporella sp. Conidiophores mononematous, (1–)2–3-septate, unbranched or 1-branced, brown olivaceous, thick- walled at below, thin-walled and colourless above, unicellular, colourless, distinct obviously differentiated apex or base (adapted from Samuels & Rossman 1987, Konta et al. 2016).

Type genusOxydothis Penz. & Sacc.

Notes – Oxydothidaceae (Konta et al. 2016) was established to accommodate the monotypic genus Oxydothis, and it is phylogenetically related to Vialaeaceae and Iodosphaeriaceae in Xylariales. Hyde et al. (2017a) provided a molecular clock estimates to evaluate the ranking of taxa of Sordariomycetes, and indicated that the status of Oxydothidaceae is supported with a divergence of 114 MYA (stem age), which is in the recommended divergence range for families (50–130 MYA).