Hysteriaceae Chevall. 1826, Flore Générale des Environs de Paris 1: 432 (1826).

MycoBank number: MB 80901; Index Fungorum number: IF 80901; Facesoffungi number: FoF 01838, 175 species.

Lignicolous or corticolous, mainly on well decorticated hardwoods, rarely on conifers. Sexual morph: Ascomata hysterothecia, dense, persistent, thick-walled, carbonaceous, distinctly navicular in outline, bearing a pronounced longitudinal slit running the length of the long axis, immersed to erumpent or entirely superficial, solitary or gregarious, ellipsoid to greatly elongated, sometimes branched, triradiate, or borne on a subiculum. Peridium thick, globose to obovoid, three-layered, composed of small pseudoparenchymatous cells, the outer layer heavily encrusted with pigment and often longitudinally striated on the surface, the middle layer lighter in pigmentation and the inner layer distinctly thin-walled, pallid, and compressed. Hamathecium comprising persistent cellular, or trabeculate, hypha-like, hyaline, septate, pseudoparaphyses, often borne in a gelatinous matrix, with tips darkened or branched at maturity above the asci. Asci 8-spored, bitunicate, fissitunicate, borne in a basal layer, typically clavate to cylindric at maturity, with a distinct ocular chamber. Ascospores overlapping 1–2-seriate, obovoid, clavate, ellipsoid or fusoid, hyaline to light- or dark- brown, 1–several-septate, or muriform; often showing bipolar asymmetry, smooth-walled, foveolate or verruculose, at times surrounded by a gel coating; contents granular, often with oil inclusions, especially when young. Asexual morph: see under notes.

TypeHysterium Pers.

Notes – Nine genera belong to this family based on morphological and phylogenetic studies viz. Gloniopsis, Graphyllium, Hysterium, Hysterobrevium, Hysterodifractum, Oedohysterium, Ostreichnion, Psiloglonium and Rhytidhysteron (Boehm et al. 2009a, b, de Almeida et al. 2014, Jayasiri et al. 2018). However, five other genera, Actidiographium, Gloniella, Hysterocarina, Hysteroglonium and Hysteropycnis also belong to Hysteriaceae based on morphological similarities (Boehm et al. 2009a). Pseudoparaphyses of Hysteriaceae are cellular (e.g. Hysterobrevium and Oedohysterium) or trabeculate (e.g. Hysterographium and Psiloglonium). Some genera have both types of pseudoparaphyses, such as Hysterium; H. doimaeensis has trabeculate (Jayasiri et al. 2018) and H. rhizophorae has cellular pseudoparaphyses (Dayarathne et al. 2020).