Occultibambusaceae D.Q. Dai & K.D. Hyde, Fungal Divers. 82(1): 25 (2017).
MycoBank number: MB 552013; Index Fungorum number: IF 552013; Facesoffungi number: FoF 01973, 15 species.
Saprobic on dead bamboo culms or teak branches, forming dark, ascostromata on raised areas, with ostiolate oppening. Sexual morph: Ascostromata solitary, scattered or gregarious, subglobose, uni- or multi-loculate, greyish to dark brown, coriaceous, with a central, papillate, rounded ostiole, internally lined with periphyses. Peridium comprising host and fungal tissues or, only fungal tissue brown and thick-walled to hyaline and thin-walled cells of textura angularis. Hamathecium comprising long, septate, cellular pseudoparaphyses, above the asci. Asci 8-spored, bitunicate, broadly cylindrical to clavate, with a short furcate pedicel, with a shallow ocular chamber. Ascospores 2–3-seriate, slightly broad fusiform, hyaline, pale brown to dark brown, 1–3- septate, surrounded by a gelatinous sheath, with guttulate cells. Asexual morph: Coelomycetous, produced on bamboo pieces on WA. Conidiomata eustromatic, immersed to partly immersed, solitary to gregarious, globose to subglobose, conical in section, dark ostiolate, with a short neck. Conidiomata wall with several layers, composed of dark to hyaline cells of textura angularis. Conidiophores reduced to conidiogenous cells. Conidiogenous cells enteroblastic, phialidic, determinate, discrete, ampulliform to cylindrical, smooth-walled. Conidia obovoid, cylindrical to oblong, hyaline to pale brown, asepate or 1–3-septate, rounded at the apex, smooth-walled, guttulate.
Type – Occultibambusa D.Q. Dai & K.D. Hyde.
Notes – Occultibambusaceae was introduced by Dai et al. (2017) to accommodate the genera Neooccultibambusa, Occultibambusa, Seriascoma and Versicolorisporium. Phookamsak et al. (2019) introduced Brunneofusispora in this family; thus, there are five genera accommodated in this family. Members of this family are normally characterized by immersed, solitary to gregarious ascomata with black ostioles, broadly cylindrical to clavate, bitunicate asci, cellular pseudoparaphyses and broad-fusiform, hyaline to dark brown ascospores with 1–3 septa, and diverse asexual morphs (Hatakeyama et al. 2008, Dai et al. 2017, Doilom et al. 2017). Species of Occultibambusaceae are reported usually on monocotyledons, but have also been found on hardwood trees. Occultibambusaceae are similar to species of Bambusicola and Lophiostoma in having fusiform ascospores and clavate asci (Zhang et al. 2009d, Dai et al. 2012, 2015). However, Bambusicola produces hyaline ascospores and asexual morphs with usually annellidic conidiogenous cells (Dai et al. 2012), while the taxa within Occultibambusaceae have brown ascospores, and no annellidic conidiogenous cells found in asexual morphs (Dai et al. 2017). Occultibambusaceae differs from Lophiostoma by its papillate ostiole, while the species of Lophiostoma are characterized in having a compressed/crest-like ostiole (Zhang et al. 2009d, Thambugala et al. 2015b).