Minutisphaeraceae Raja, Oberlies, Shearer & A.N. Mill., Mycologia 107 (4): 854 (2015).
MycoBank number: MB 811062; Index Fungorum number: IF 811062; Facesoffungi number: FoF 08066, 4 species.
Saprobic on submerged wood in freshwater habitats. Sexual morph: Ascomata pseudothecioid or apothecioid, erumpent to superficial, brown, with an ostiole and irregularly curved, dark brown to black hypha-like structures around the ostiole. Peridium thin-walled, composed of cells of textura angularis to textura globosum. Hamathecium comprising septate, cellular pseudoparaphyses with or without enlarged pigmented tips. Asci 8-spored, fissitunicate, ovoid to obclavate, sessile to short-pedicellate, apically rounded with or without an ocular chamber. Ascospores 2–4-seriate, clavate, fusiform to ellipsoidal, hyaline or pale brown septate, multiguttulate, smooth or rough-walled, with gelatinous sheath, with or without filamentous appendages radiating around the mid-septum. Asexual morph: Undetermined.
Type: Minutisphaera Shearer, A.N. Mill. & A. Ferrer, Ferrer et al.
Notes: This monotypic family was established by Raja et al. (2015) to accommodate Minutisphaera. Raja et al. (2015) placed Minutisphaeraceae in a newly introduced order Minutisphaerales, Dothideomycetes based on its distinct morphological characters and multi-gene phylogenies. The morphological characters such as small, globose to subglobose, ostiolate ascomata, septate, cellular pseudoparaphyses, fissitunicate, ovoid to obclavate asci and hyaline to brown, 1-septate, ascospores with or without a gelatinous sheath, suggest that Minutisphaeraceae could be placed in Pleosporales (Zhang et al. 2012). Nevertheless, the molecular phylogenetic analysis shows that the family has no relationship with the members of Pleosporales (Raja et al. 2015; Liu et al. 2017). Bao et al. (2019) provided a new species of Minutisphaera. All the taxa of Minutisphaeraceae are freshwater fungi occurring on submerged woody substrates.