The newly discovered systematic placement of Bactrodesmium abruptum, the lectotype species of the genus, prompted a re-evaluation of the traditionally broadly conceived genus Bactrodesmium. Fresh material, axenic cultures and new DNA sequence data of five gene regions of six species, i.e. B. abruptum, B. diversum, B. leptopus, B. obovatum, B. pallidum and B. spilomeum, were studied. Bactrodesmium is a strongly resolved lineage in the Savoryellales (Sordariomycetes), supported by Bayesian and Maximum Likelihood methods. The genus Bactrodesmium is emended and delimited to hyphomycetes characterised by sporodochial conidiomata, mononematous often fasciculate conidiophores, holoblastic conidiogenesis and acrogenous, solitary, dry, pigmented, transversely or rarely longitudinally septate conidia. The conidia are seceding rhexolytically, exhibiting multiple secession patterns. An identification key to 35 species accepted in Bactrodesmium is given, providing the most important diagnostic characters. Novel DNA sequence data of B. longisporum and B. stilboideum confirmed their placement in the Sclerococcales (Eurotiomycetes). For other Bactrodesmium, molecular data are available for B. cubense and B. gabretae, which position them in the Dothideomycetes and Leotiomycetes, respectively. All four species are excluded from Bactrodesmium and segregated into new genera, Aphanodesmium, Gamsomyces and Kaseifertia. Classification of 20 other species and varieties not recognised in the genus is discussed. Based on new collections of Dematiosporium aquaticum, the type species of Dematiosporium, the genus is emended to accommodate monodictys-like freshwater lignicolous fungi of the Savoryellales characterised by effuse colonies, holoblastic conidiogenous cells and dictyosporous, pigmented conidia with a pore in each cell. Study of additional new collections, cultures and DNA sequence data revealed several unknown species, which are proposed as taxonomic novelties in the Savoryellales and closely related Pleurotheciales. Ascotaiwania latericolla, Helicoascotaiwania lacustris and Pleurotheciella erumpens are described from terrestrial, lentic and lotic habitats from New Zealand and France, respectively. New combinations are proposed for Helicoascotaiwania farinosa and Neoascotaiwania fusiformis. Relationships and systematics of the Savoryellales are discussed in the light of recent phylogenies and morphological patterns newly linked with the order through cultural studies.

• Keywords
• 12 taxonomic novelties, Aphanodesmium Réblová & Hern.-Restr., Aphanodesmium gabretae (Koukol & Kolářová) Réblová & Hern.-Restr., Ascotaiwania latericolla Réblová, Hern.-Restr. & J. Fourn., Conidial secession, Conidiogenesis, Gamsomyces Hern.-Restr. & Réblová, Gamsomyces longisporus (M.B. Ellis) Hern.-Restr. & Réblová, Gamsomyces stilboideus (R.F. Castañeda & G.R.W. Arnold) Hern.-Restr. & Réblová, Helicoascotaiwania farinosa (Linder) Réblová, Hern.-Restr. & J. Fourn., Helicoascotaiwania lacustris Réblová & J. Fourn., Kaseifertia Réblová, Hern.-Restr. & J. Fourn, Kaseifertia cubense (R.F. Castañeda & G.R.W. Arnold) Réblová, Hern.-Restr. & J. Fourn., Molecular systematics, Neoascotaiwania fusiformis (Jing Yang, Bhat & K.D. Hyde) Réblová, Hern.-Restr. & J. Fourn, Pleurotheciella erumpens Réblová & J. Fourn, Sporodochium, Synnema, Wood-inhabiting fungi,
• Publication type
• Journal Article MeSH

The genus Ceratostomella has a long history of taxonomic confusion. While species with evanescent asci have been transferred to the Microascales and Ophiostomatales, the taxonomic status of species with persistent asci has not been completely resolved. In previous studies using DNA sequence data, cultures and morphology, several Ceratostomella spp. were allocated in 13 genera in the Eurotiomycetes and Sordariomycetes. In our study, the systematics of the remaining Ceratostomella spp. with persistent asci is revisited with new collection data, cultures and phylogeny based on novel DNA sequences from six nuclear loci. Bayesian inference and Maximum Likelihood analyses support the monophyly of several wood-inhabiting species formerly classified in Ceratostomella and other unknown morphologically similar taxa and their division into four genera, i.e. Lentomitella, Spadicoides, Torrentispora and the newly described Calyptosphaeria. This robust clade represents the order Xenospadicoidales in the Sordariomycetidae. Comparative analysis of the ITS2 secondary structure revealed a genetic variation among Lentomitella isolates; 11 species were recognised, of which five are newly introduced and two are new combinations. Other taxonomic novelties include four new species and eight new combinations in Calyptosphaeria, Spadicoides, and Torrentispora. Molecular data suggest that Spadicoides is polyphyletic. The core of the genus is positioned in the Xenospadicoidales; Spadicoides s. str. is experimentally linked with sexual morphs for the first time. Based on DNA sequence data, the monotypic genera Xenospadicoides and Pseudodiplococcium are reduced to synonymy under Spadicoides, while Fusoidispora and Pseudoannulatascus are synonymised with Torrentispora. Members of the Xenospadicoidales inhabit decaying wood in terrestrial and freshwater environments and share a few morphological characters such as the absence of stromatic tissue, ascomata with a cylindrical or rostrate neck, similar anatomies of the ascomatal walls, thin-walled unitunicate asci with a non-amyloid apical annulus, disintegrating paraphyses, usually ellipsoidal to fusiform ascospores and holoblastic-denticulate or tretic conidiogenesis. Revised Ceratostomella spp. with persistent asci are listed and the taxonomic status of each species is re-evaluated based on revision of the holotype and other representative material, published details and available phylogenetic data.

• Keywords
• C. tenebrosa Réblová & A.N. Mill., C. tropica (Huhndorf et al.) Réblová & A.N. Mill., Calyptosphaeria Réblová & A.N. Mill, Calyptosphaeria collapsa Réblová & A.N. Mill., Calyptosphaeria subdenudata (Peck) Réblová & A.N. Mill., Ceratostomella, Conidiogenesis, Holoblastic-denticulate, L. investita (Schw.) Réblová, L. obscura Réblová, L. striatella Réblová, L. sulcata Réblová, L. tenuirostris Réblová, Lentomitella conoidea (Feltg.) Réblová, Lentomitella magna Réblová, Molecular systematics, New taxa, Phaeoisaria-like, S. hyalostoma (Munk) Réblová, Selenosporella-like, Spadicoides fuscolutea (Rehm) Réblová, Spadicoides iberica (Hern.-Restr. et al.) Réblová & A.N. Mill., T. biatriispora (K.D. Hyde) Réblová & A.N. Mill., T. dubia (Sacc.) Réblová & A.N. Mill, T. novae-zelandiae Réblová & A.N. Mill, Taxonomy, Torrentispora aquatica (Vijaykr. et al.) Réblová & A.N. Mill., Torrentispora calembola Réblová & A.N. Mill., Tretic, Xenospadicoidales,
• Publication type
• Journal Article MeSH

Phylogenetic analyses of DNA sequences from nuclear ribosomal and protein-coding loci support the placement of several perithecial ascomycetes and dematiaceous hyphomycetes from freshwater and terrestrial environments in two monophyletic clades closely related to the Savoryellales. One clade formed by five species of Conioscypha and a second clade containing several genera of uncertain taxonomic status centred on Pleurothecium, represent two distinct taxonomic groups at the ordinal systematic rank. They are proposed as new orders, the Conioscyphales and Pleurotheciales. Several taxonomic novelties are introduced in the Pleurotheciales, i.e. two new genera (Adelosphaeria and Melanotrigonum), three novel species (A. catenata, M. ovale, Phaeoisaria fasciculata) and a new combination (Pleurotheciella uniseptata). A new combination is proposed for Savoryella limnetica in Ascotaiwania s.str. based on molecular data and culture characters. A strongly supported lineage containing a new genus Plagiascoma, species of Bactrodesmiastrum and Ascotaiwania persoonii, was identified as a sister to the Conioscyphales/Pleurotheciales/Savoryellales clade in our multilocus phylogeny. Together, they are nested in a monophyly in the Hypocreomycetidae, significantly supported by Bayesian inference and Maximum Likelihood analyses. Members of this clade share a few morphological characters, such as the absence of stromatic tissue or clypeus, similar anatomies of the 2-layered ascomatal walls, thin-walled unitunicate asci with a distinct, non-amyloid apical annulus, symmetrical, transversely septate ascospores and holoblastic conidiogenesis. They represent the only fungi in the Hypocreomycetidae with apically free, filiform to cylindrical, persistent or partially disintegrating paraphyses. The systematic placement of two other dematiaceous hyphomycetes was resolved based on DNA sequences; Phragmocephala stemphylioides is a member of the Pleurotheciales and Triadelphia uniseptata is within the Savoryellales.

• Keywords
• Hypocreomycetidae, Phaeoisaria, freshwater fungi, holoblastic conidiogenesis, multigene analysis, systematics,
• Publication type
• Journal Article MeSH