Eremomycetaceae Malloch & Cain, Can. J. Bot. 49: 847 (1971).
MycoBank number: MB 80751; Index Fungorum number: IF 80751; Facesoffungi number: FoF 05359, 3 species.
Saprobic, isolated primarily on animal dung or soil. Colonies flocculent, drift white, superficial, dense, and growing slowly on agar media. Hyphae septate, branch, hyaline to brown. Sexual morph: Ascomata sphaerical to ellipsoid, solitary, scattered, superficial on hyphae, or submerged in the agar, dark brown to black, lacking ostioles, but tending to split open before maturity. Peridium thin, pseudoparenchymatous, composed of large brown cells of textura angularis. Hamathecium lacking pseudoparaphyses. Asci irregularly disposed within the ascoma, 8-spored, bitunicate, not fissitunicate, obovoid to clavate, thin-walled, pedicellate, and evanescent. Ascospores multi-seriate, small, often fabiform to broadly oblate, hyaline to pale brown, aseptate, smooth-walled to slightly verrucose. Asexual morph: Coelomycetous or hyphomycetous. Pycnidia globose to subglobose, thin-walled, papillate. Conidiophores filiform, septate, hyaline to brown. Conidia ellipsoidal, hyaline, aseptate, thin- walled, guttulate.
Type: Eremomyces Malloch & Cain.
Notes: Malloch and Cain (1971) introduced Eremomycetaceae for species having solitary ascomata and hyaline, aseptate ascospores. Eremomycetaceae consists of three species: Eremomyces bilateralis, Rhexothecium globosum, and Pithoascus langeronii, (= Eremomyces langeronii). Eremomycetaceae are most similar to Pseudeurotiaceae (Malloch and Sigler 1988), but differ in ascomatal initials (coiled in Pseudeurotiaceae, pseudoparenchymatous in Eremomycetaceae). Eremomycetaceae comprises two genera Eremomyces, the type genus and Rhexothecium (Lumbsch and Huhndorf 2010). Eremomyces has fabiform and hyaline ascospores, while Rhexothecium has broadly oblate and pale yellow to brown ascospores. Eremomyces is more similar to Trichosporiella (Helotiales) in having subglobose to globose, black conidiomata and scopulariopsis-like hyaline conidia. Rhexothecium resembles Trichosporiella (Helotiales) in having solitary to catenulate, lateral, and hyaline, basic truncate conidia. Species of Eremomycetaceae are distributed worldwide and can be commonly found in Egypt, Kenya, North America and the Netherlands. Wijayawardene et al. (2018) included Arthrographis in Eremomycetaceae, while Liu et al. (2017) included Arthrographis in a new family Arthrographaceae. However, whether Arthrographaceae is valid or not is unclear as there is no mention of this family in the literature or in Index Fungorum. Members of both Arthrographis and Eremomyces produce hyaline to subhyaline conidia, however Arthrographis is distinct in producing unicellular arthroconidia and chlamydospores which are absent in Eremomyces. We include Arthrographis in Eremomycetales, genera incertae sedis until further studies are carried out.