Phaeoacremonium W. Gams, Crous & M.J. Wingf., Mycologia 88(5): 789 (1996)
Diaporthomycetidae, Togniniales, Togniniaceae, Phaeoacremonium
Index Fungorum number: IF27679; Facesoffungi number: FoF 02140; 63 morphological species, 62 species with sequence data.
Saprobic on dead wood or pathogenic on human and various woody plants, frequently associated with Petri and Esca disease of grapevines. Sexual morph: Ascomata perithecial, black, superficial to sub-immersed, astromatic, globose to subglobose base, with straight or flexuous, periphysate ostiole. Peridium fragile to leathery, two-layered, the outer layer comprising thin-walled, brown cells of textura prismatica to textura angularis, the inner layer comprising non-pigmented flattened cells. Paraphyses abundant, hyaline, branching, septate, attenuate towards the apex, slightly constricted at septa. Ascogenous hyphae hyaline, elongate, branched, smooth-walled, sympodial, bearing remnant of base from which a single ascus is produced. Asci 8-spored, unitunicate, clavate, with obtuse, sessile bases and thickened ascal apex without a discharge mechanism, aggregating in spicate arrangement. Ascospores 3–4-seriate, hyaline, aseptate, allantoid, oblong-ellipsoidal, slightly curved, with rounded ends. Asexual morph: Hyphomycetous. Mycelium mid-brown, dense, branched, septate, some species produce wart-like droplets. Conidiophores arising from bundled or single mycelium, branched at base or unbranched, septate, pale brown, paler towards the apex, with small warts or verruculose ornamentations at the base, percurrent rejuvenation. Conidiogenous cells usually monophialidic, integrated or discrete, hyaline to pale brown, with or without basal septum. Conidia hyaline, septate, smooth-walled, cylindrical, oblong-ellipsoidal or allantoid, straight or slightly curved, generally adhering in globose head at the tip of phialides (adapted from Réblová et al. 2004).
Type species: Phaeoacremonium parasiticum (Ajello, Georg & C.J.K. Wang) W. Gams, Crous & M.J. Wingf., in Crous, Gams, Wingfield & Wyk, Mycologia 88(5): 794 (1996)
Notes: Phaeoacremonium was introduced by Crous et al. (1996) for five new species with P. parasiticum as the type species. They mentioned this genus is similar to Phialophora and Acremonium. Mostert et al. (2003) confirmed Phaeoacremonium as the asexual morph of Togninia based on their morphological comparison, sexual compatibility and DNA phylogeny. Togninia was introduced by Berlese (1990) with Togninia minima as the type species. Togninia has previously classified in Calosphaeriaceae, Calosphaeriales (Berlese 1900, Barr 1985, Mostert et al. 2003). Réblová et al. (2004) erected Togniniaceae in Diaporthales to accommodate Phaeoacremonium and Togninia based on phylogenetic analysis of LSU and SSU sequence data. Subsequently, Mostert et al. (2006) added several species to both Phaeoacremonium and Togninia, coupled with the generic descriptions. Currently, 67 epithets of Phaeoacremonium are listed in Index Fungorum (2020). Among them, Phaeoacremonium chlamydosporum was transferred to Phaeomoniella (Gams & Crous 2000). Phaeoacremonium aleophilum, P. mortoniae and P. novae-zealandiae were synonymized under P. minimum, P. fraxinopennsylvanicum and P. leptorrhynchum, respectively (Réblova 2011, Gramaje et al. 2015). To date, 63 species are accepted in this genus, of which P.aquaticumonly have ITS gene sequence available. For P.inconspicuum, no ex-type culture or DNA exists (Gramaje et al. 2015). The remaining 62 species have been confirmed with molecular data.
Phaeoacremonium inconspicuum (Rehm) Gramaje, L. Mostert & Crous
Phaeoacremonium krajdenii L. Mostert, Summerb. & Crous, in Mostert
Barr ME. 1985 – Notes on the Calosphaeriales. Mycologia 77, 549–565.
Berlese AN. 1900 – Icones Fungorum ad usum Sylloges Saccardianae adcommodatae. 3. Sphaeriaceae allantosporae. Cramer, Padova 3, 1–120.
Crous PW, Peerally A. 1996 – Gliocladiopsis irregulare sp. nov. and notes on Cylindrocladium spathiphylli. Mycotaxon 58, 119–128.
Gams W, Crous PW. 2000 – Phaeomoniella chlamydospora gen. et comb. nov., a causal organism of Petri grapevine decline and esca. Phytopathologia mediterranea 39, 112–118.
Gramaje D, Mostert L, Groenewald JZ, Crous PW. 2015 – Phaeoacremonium: from esca disease to phaeohyphomycosis. Fungal Biology 119, 759–783.
Index Fungorum. 2020 – http://www.indexfungorum.org/Names/Names.asp.
Mostert L, Crous PW, Ewald Groenewald JZ, Gams W et al. 2003 – Togninia (Calosphaeriales) is confirmed as teleomorph of Phaeoacremonium by means of morphology, sexual compatibility and DNA phylogeny. Mycologia 95, 646–659.
Mostert L, Groenewald JZ, Summerbell RC, Gams W et al. 2006 – Taxonomy and pathology of Togninia (Diaporthales) and its Phaeoacremonium anamorphs. Studies in Mycology 54, 1–113.
Réblová M. 2004 – Four new species of Chaetosphaeria from New Zealand and redescription of Dictyochaeta fuegiana. Studies in Mycology 50, 171–186.
Réblová M. 2011 – New insights into the systematics and phylogeny of the genus Jattaea and similar fungi of the Calosphaeriales. Fungal Diversity 49, 167‒198.