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.

• Klíčová slova
• 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,
• Publikační typ
• časopisecké články MeSH

The genus Cheiromycina is one of the few genera of lichenized hyphomycetes for which no sexual reproductive stages have been observed. The genus includes species from boreal to temperate regions of the Northern Hemisphere where it is found growing on bark or wood. Congeners in Cheiromycina are characterized by a noncorticate thallus, nearly immersed in the substrate and presenting powdery unpigmented sporodochia, and containing chlorococcoid photobionts. The relationships of members of Cheiromycina with other fungi are not known. Here we inferred the phylogenetic placement of Cheiromycina using three loci (nuSSU, nuLSU, and mtSSU) representing C. flabelliformis, the type species for the genus, C. petri, and C. reimeri. Our results revealed that the genus Cheiromycina is found within the family Malmideaceae (Lecanorales) where members formed a monophyletic clade sister to the genera Savoronala and Malmidea. This phylogenetic placement and the relationships of Cheiromycina with other lichenized hyphomycetous taxa are here discussed.

• Klíčová slova
• Cheiroid conidia, Lecanorales, Malmideaceae, mycobiont, ribosomal DNA, symbiosis,
• MeSH
• Ascomycota klasifikace   cytologie   genetika   MeSH
• DNA fungální genetika   MeSH
• fylogeneze * MeSH
• kůra rostlin mikrobiologie   MeSH
• lišejníky mikrobiologie   MeSH
• mitosporické houby klasifikace   cytologie   genetika   MeSH
• RNA ribozomální 18S genetika   MeSH
• RNA ribozomální 28S genetika   MeSH
• RNA ribozomální genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa MeSH
• Spojené státy americké MeSH
• Názvy látek
• DNA fungální MeSH
• RNA ribozomální 18S MeSH
• RNA ribozomální 28S MeSH
• RNA ribozomální MeSH
• RNA, ribosomal, 12S MeSH Prohlížeč

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.

• Klíčová slova
• Hypocreomycetidae, Phaeoisaria, freshwater fungi, holoblastic conidiogenesis, multigene analysis, systematics,
• Publikační typ
• časopisecké články MeSH