Cyclothyriellaceae Jaklitsch & Voglmayr, Stud. Mycol. 85: 39 (2016).

MycoBank number: MB 817772; Index Fungorum number: IF 817772; Facesoffungi number: FoF 08192, 21 species.

On bark of moderately decayed twigs, often on and in association with other fungi. Sexual morph: Ascomata commonly clustered in valsoid configuration within KOH-positive tissue or in purple-coloured plant tissue or scattered, immersed to erumpent, more or less globose, black. Peridium pseudoparenchymatous. Ostiolar discs brightly coloured or black, ostioles periphysate. Hamathecium comprising apically free paraphyses, narrow branched, and anastomosing, trabeculate pseudoparaphyses. Asci 8-spored, bitunicate, cylindrical to clavate. Ascospores 1-seriate, ellipsoid to fusoid, brown, with several eusepta, thick-walled, with or without a sheath. Asexual morph: pycnidial, historically called aposphaeria-like. Peridium pseudoparenchymatous, consisting of dark cells. Conidiophores reduced to conidiogenous cells, or inconspicuous. Conidiogenous cells phialidic. Conidia cylindrical, oblong to ellipsoid, hyaline or brown, 1-celled, smooth-walled (Jaklitsch & Voglmayr 2016).

TypeCyclothyriella Jaklitsch & Voglmayr.

Notes – The family was established by Jaklitsch & Voglmayr (2016) to accommodate the distinct clade containing Cyclothyriella based on C. rubronotata and Massariosphaeria based on M. phaeospora.