Chaetosphaeriaceae Réblová, M.E. Barr & Samuels, Sydowia 51(1): 56 (1999)

MycoBank number: MB 82100; Index Fungorum number: IF 82100; Facesoffungi number: FoF 01139; 658 species.

Saprobic on wood or decaying plant parts including leaves, fruits in terrestrial and aquatic habitats, sometimes isolated from soil and fresh plant parts such as leaves, less commonly –pathogenic. Sexual morph: Ascomata perithecial, gregarious or scattered, solitary, superficial or basally immersed on a thin stroma or on a thin subiculum, ovoid, globose to subglobose, carbonaceous, coriaceous or membranaceous, dark brown to black, rough, smooth or with short setae, papillate, the apex collapsing when dry. Ostiole lined with hyaline periphyses or periphyses absent. Subiculum thin, scanty, brown to dark brown, septate, of unbranched hyphae. Peridium composed of two layers, outer layer comprising brown cells of textura epidermoidea or angularis, carbonaceous; inner layer comprising hyaline cells of textura prismatica, thin, membranaceus. Paraphyses numerous, septate, unbranched, tapering, filiform or cylindrical. Asci 8-spored, unitunicate, thin-walled, clavate to cylindrical, long or short pedicellate, with J-, apical ring. Ascospores 2–3-seriate, fusiform, cylindrical to ellipsoid, straight or sometimes curved, 0–3- septate, with or without fragmenting, hyaline or brown or becoming dark coloured in part, smooth or striate, with guttules, sheath or appendages. Asexual morph: Hyphomycetous or coelomycetous. When hyphomycetous, Conidiophores macronematous, mononematous, scattered or gregarious, dark brown or hyaline, straight or flexuous, septate, branched or unbranched, with short encircling collar hyphae. Conidiogenous cells monophialidic or polyphialidic, holoblastic or enteroblastic, proliferating percurrently or sympodial, hyaline, with a distinct funnel-shaped collarette, smooth- walled. Conidia aggregated, continuous or mucilaginous, aseptate to multi-septate, flexuous, fusiform, allantoid, cylindrical or doliiform, curved or straight, hyaline to dark brown. When coelomycetous, Conidiomata stromatic, scattered or aggregated, superficial, cupuliform or globose, unilocular, setose, comprising black to dark brown cells of textura angularis or intricata. Setae numerous, black to brown, septate, ovoid to cylindrical or arising from the outer elements of excipulum, smooth, thick-walled, multi-septate. Conidiophores lining the basal stroma in a dense layer or arising from conidiomatal cavity, brown, 4–6-septate, unbranched, cylindrical, thin-walled, smooth. Conidiogenous cells integrated, determinate, holoblastic or enteroblastic, phialidic with conspicuous periclinal thickening at an attenuated apex, brown, smooth, subcylindrical to lageniform. Conidia aseptate, globose to subglobose or ellipsoid, fusiform to allantoid, curved or straight, obtuse to sub-obtusely rounded at apex, truncate at base, eguttulate or guttulate, hyaline to brown, thin, smooth-walled, with a single, cellular, unbranched, flexuous, with tubular appendage at each end, separated by a septum, with basal asymmetrically located appendage.

Type genus – Chaetosphaeria Tul. & C. Tul.

Notes – Chaetosphaeriaceae was introduced without any description by Locquin (1984) to accommodate five genera including Chaetosphaeria, Loramyces, Niesslia, Rhagadostoma, and Zignöella. This was not considered as a validly published family (Hawksworth & David 1989 – Art. 36.1, Grueter et al. 1994). Hence, Réblová et al. (1999) re-introduced the family based on Chaetosphaeria, to accommodate another six genera: Ascocodinaea, Melanochaeta, Melanopsammella, Porosphaerella, Porosphaerellopsis, and Striatosphaeria. Réblová et al. (1999) maintained Chaetosphaeriaceae in Sordariales based on morphology. Based on LSU sequence data, Huhndorf (2004b) placed the family in Chaetosphaeriales. Subsequently more genera were added to the family and, Maharachchikumbura et al. (2016b) accepted 37 genera. Maharachchikumbura et al. (2016b) aknowledged the taxonomic confusion of genera in the family and the need for a monograph with molecular support for accepted genera. Crous et al. (2016a) introduced Adautomilanezia and Eucalyptostroma to Chaetosphaeriaceae. Ma et al. (2016b) introduced the hyphomycetes genus Anacacumisporium based on phylogenetic analyses. Five genera, Codinaeopsis, Dictyochaetopsis, Phaeostalagmus, Phialogeniculata and Zignoëlla, previously listed by Maharachchikumbura et al. (2016b) in Chaetosphaeriaceae, were not considered by Wijayawardene et al. (2018a). Wijayawardene et al. (2018a) listed 38 genera in Chaetosphaeriaceae including Adautomilanezia, Anacacumisporium, Conicomyces, Eucalyptostroma, Menisporopsis and Pseudolachnella. Yang et al. (2018a) placed Nawawia and Phialosporostilbe in Chaetosphaeriaceae based on LSU and ITS sequence data. A new genus Multiguttulispora was added to the family by Lin et al. (2019b). Crous et al. (2018d) provided first DNA sequence data for Polynema and placed it in Chaetosphaeriaceae. In this entry the sexual morph of Chaetosphaeria jonesii and the asexual morph of a new species, Chloridium submersum, is illustrated.

Genera