Amphisphaeria Ces. & De Not., Comm. Soc. crittog. Ital. 1(fasc. 4): 223 (1863)
Xylariomycetidae, Amphisphaeriales, Amphisphaeriaceae, Amphisphaeria
Index Fungorum number: IF173; 88 morphological species (Species Fungorum 2020); 18 morphological species (Senanayake et al. 2019); 6 species with sequence data.
Saprobic on woody substrates in aquatic, terrestrial and mangrove habitats. Sexual morph: usually visible as slightly raised, black dots on surface of host, regularly surrounded by a light or darkened, halo-like area. Pseudostromata when present, comprising brown to black fungal hyphae and host cells. Clypeus not well developed. Ascomata perithecial, solitary or aggregated, scattered, immersed to erumpent, rarely superficial, coriaceous, subglobose, globose or ellipsoidal, dark brown, ostiolate, papillate. Papilla erumpent through host surface, conical, narrow, regularly umbilicate, containing filamentous hyaline periphyses. Peridium 2-layered; outer layer containing thick-walled, dark brown cells of textura angularis, inner layer made up of thin-walled, hyaline cells of textura prismatica. Paraphyses filamentous, septate, slightly tapering at the apex. Asci unitunicate, 8-spored, cylindrical, short-pedicellate, rounded apex, with J+ or J-, apical ring. Ascospores uniseriate to overlapping uniseriate, light to dark brown, ellipsoidal to fusiform, seldom curved, 1–3-septate, not or faintly constricted at the septum, smooth-walled, sometimes guttulate, with or without gelatinous sheath. Asexual morph: Coelomycetous. Conidiomata solitary or clustered, subglobose to globose, dark brown. Conidiomatal wall made up of thick-walled, septate, brown mycelium. Conidiophores branched, septate, hyaline to light brown, thick-walled. Conidiogenous cells septate, elongated, hyaline, thin-walled, annellidic. Conidia 1-celled, elongate to fusiform, hyaline, smooth-walled, with or without appendage originating from the middle of conidia (adapted from Hyde et al. 2020, Samarakoon et al. 2020).
Type species: Amphisphaeria umbrina (Fr.) De Not., Sfer. Ital.: 69 (1863)
Notes: Amphisphaeria was introduced by Cesati & De Notaris (1863). Wang et al. (2004) re-examined more than 170 type species described as Amphisphaeria and accepted 12 species. Senanayake et al. (2015) reviewed the phylogenetic status of the genus, which is sister to
Lepteutypa (Jaklitsch et al. 2016). Based on phylogenetic investigations, other six new species have been added: A. doidgeae (Marincowitz et al. 2008), A. sorbi (Liu et al. 2015), A. mangrovei (Phookamsak et al. 2019), A. flava, A. thailandica (Samarakoon et al. 2019) and A. acericola (Senanayake et al. 2019) respectively.
Species illustrated in this entry:
Amphisphaeria sorbi Senan. & K.D. Hyde
Amphisphaeria acericola Senan., Camporesi & K.D. Hyde