Ophiostomataceae Nannf., Nova Acta R. Soc. Scient. upsal., Ser. 4 8(no. 2): 30 (1932)
Index Fungorum number: IF91154; Facesoffungi number: FoF01807; 353 species.
Saprobic or parasitic on woody plants, occasionally on herbaceous plants, symbionts of or
associated with beetles and mites. Sexual morph: Ascomata superficial, perithecial or cleistothecial,
globose to subglobose, with external hairs, pale brown, dark brown or black, with long or short
ostiolar necks, or sometimes lacking ostioles. Ostiolar neck short or long, slender, straight or
flexuous, brown to dark brown at the base, pale brown to hyaline at the apex, containing parallel
hyphae with pigmented cell walls around the ostiole. Ostiolar hyphae present or absent; when
present, convergent or divergent, filamentous, septate, pale brown to hyaline, with some genera
containing ostiolar beak (e.g. Subbaromyces). Peridium pseudoparenchymatous, with outer wall
layers composed of angular cells with thickened, pigmented walls, and lined by thin–walled,
hyaline cells of textura angularis. Asci 8–spored, unitunicate, evanescent, fusiform, oblong to
clavate, some genera globose to subglobose (e.g. Fragosphaeria), with thin, deliquescent walls.
Ascospores bi– to multi–seriate, variable in shape, frequently asymmetrical, oval, allantoid,
fusiform, cylindrical, ellipsoidal, reniform, or falcate, aseptate or 1–septate, hyaline or appearing
yellowish in mass, with or without a sheath. Asexual morph: Hyphomycetous. Conidiophores
mononematous or synnematous, simple or branched, with some bearing a brush–like apical
branching structure (e.g. Leptographium), erect, hyaline or dark brown to black. Conidiogenous
cells holoblastic, polyblasic, sympodial, denticulate, phiailidic, with some proliferating at or
somewhat below the apex and giving rise to another series of denticles or conidiogenous loci (e.g.
Ophiostoma, Sporothrix). Conidia solitary or aggregated, fusiform, obovate to oblong, cylindrical,
aseptate, hyaline, some bearing conidia in a viscoid pale reddish–brown head (e.g. pesotum–like)
(adapted from Maharachchikumbura et al. 2016b).
Type genus – Ophiostoma Syd. & P. Syd.
Notes – Ophiostomataceae was originally described with three genera (Ophiostoma,
Ceratostomella, Endoconidiophora) (Nannfeldt 1932). de Beer et al. (2013a) accepted six genera
(Ceratocystiopsis, Ophiostoma, Fragosphaeria, Leptographium, Raffaelea, Graphium) based on
phylogenetic analyses. Maharachchikumbura et al. (2015, 2016b) provided an updated outline of
Ophiostomataceae with 12 genera (Ceratocystiopsis, Fragosphaeria, Hyalobelemnospora,
Hyalorhinocladiella, Klasterskya, Leptographium,Ophiostoma, Pesotum,Phialographium,
Raffaelea,Spumatoria,Subbaromyces), which included sexual and asexual morphs, based on a
phylogenetic analysis.Pesotum and Hyalorhinocladiella appear to be synonyms of Ophiostoma,
but this may need further study. de Beer et al. (2016a) accepted Sporothrixin Ophiostomatales
based on DNA sequence data and morphology of both morphs. Bateman et al. (2016) introduced
Afroraffaelea. We accept 13 genera based on previous research (Afroraffaelea, Aureovirgo,
Ceratocystiopsis, Fragosphaeria, Graphilbum, Hawksworthiomyces, Klasterskya, Leptographium,
Ophiostoma, Raffaelea, Sporothrix, Spumatoria, and Subbaromyces) (Bateman et al. 2016, de Beer
et al. 2013a, 2016a, Maharachchikumbura et al. 2015b, 2016b).
Ecological and economic significance of Ophiostomataceae
Members of this family are mostly saprobes on sap–wood. Species are specialized with sticky
spores to facilitate insect dispersal. Many bark beetles act as vectors of ophiostomatoid fungi, e.g.
Ophiostoma, Leptographium, Ceratocytiopsis species (Upadhyay 1981, Wingfield et al. 1993,
Jacobs & Wingfield 2001, Zipfel et al. 2006). Most species cause sap stain or blue stain of freshly
cut logs and affect timber quality (Seifert 1993), and several species are important pathogens on
species of Protea, Pinus, Larix, Tsuga and Pistacia and other tree species (Wingfield et al. 1988,
Jacobs & Wingfield 2001, Roets et al. 2013, Zhou et al. 2013)