Acanthostigmina Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 118: 1499 (1909)
Saprobic on rotten wood, widespread in tropical regions. Sexual morph: Ascomata superficial, solitary, scattered or clustered, globose to subglobose, dark brown, ostiolate, surrounded by sparse, dark brown to black setae; setae relatively long, tapering to an acute apex. Peridium thick, comprising several layers of textura angularis to subglobosa, inwardly comprising brown to reddish-brown, small brown cells of textura subprismatica. Hamathecium comprising numerous, filiform, septate, branched, hyaline and pale brown pseudoparaphyses, embedded in a gelatinous matrix. Asci 8-spored, bitunicate, broadly cylindric-subclavate, pedicellate, thickened at apex, without an ocular chamber. Ascospores 2–3-seriate, elongate, cylindric-fusiform, curved, tapering towards sub-rounded ends, less than 10-septate, slightly constricted at septum, hyaline when young and pale brown at maturity, some surrounded by a mucilaginous sheath, smooth walled. Asexual morph: Unknown (adapted from Boonmee et al. 2014).
Type species: Acanthostigmina minuta (Fuckel) Clem. & Shear
Notes: Acanthostigmina is characterised by globose to subglobose, dark brown ascomata covered by sparse dark brown to black setae, and asci which are cylindric-subclavate with curved fusiform ascospores. Acanthostigmina is morphologically and phylogenetically a distinct genus in Tubeufiaceae. Molecular markers available for Acanthostigmina are ITS, LSU, SSU and TEF-1.