Thirteen morphologically similar strains of barbatosphaeria- and tectonidula-like fungi were studied based on the comparison of cultural and morphological features of sexual and asexual morphs and phylogenetic analyses of five nuclear loci, i.e. internal transcribed spacer rDNA operon (ITS), large and small subunit nuclear ribosomal DNA, β-tubulin, and second largest subunit of RNA polymerase II. Phylogenetic results were supported by in-depth comparative analyses of common core secondary structure of ITS1 and ITS2 in all strains and the identification of non-conserved, co-evolving nucleotides that maintain base pairing in the RNA transcript. Barbatosphaeria is defined as a well-supported monophyletic clade comprising several lineages and is placed in the Sordariomycetes incertae sedis. The genus is expanded to encompass nine species with both septate and non-septate ascospores in clavate, stipitate asci with a non-amyloid apical annulus and non-stromatic ascomata with a long decumbent neck and carbonised wall often covered by pubescence. The asexual morphs are dematiaceous hyphomycetes with holoblastic conidiogenesis belonging to Ramichloridium and Sporothrix types. The morphologically similar Tectonidula, represented by the type species T. hippocrepida, grouped with members of Barbatosphaeria and is transferred to that genus. Four new species are introduced and three new combinations in Barbatosphaeria are proposed. A dichotomous key to species accepted in the genus is provided.

• Klíčová slova
• Ramichloridium, Sporothrix, Tectonidula, phylogenetics, sequence analysis, spacer regions,
• Publikační typ
• časopisecké články MeSH

Two morphologically similar groups of ascomycetes with globose to subglobose perithecia, elongate necks, unitunicate asci floating freely at maturity, and hyaline ascospores currently placed in Calosphaeria s. lat. and Ceratostomella s. lat., respectively, are studied. The Calosphaeria-like fungi have groups of perithecia growing between cortex and wood, arranged in circular groups with converging necks and piercing the cortex in a common point; the asci with a shallow apical ring and U- to horseshoe-shaped hyaline ascospores are compared with Calosphaeria pulchella, the type species of the genus. Conidiogenesis of the investigated Calosphaeria-like fungi is holoblastic-denticulate; ramichloridium-like and sporothrix-like conidiophores and conidia were formed in vitro. Ascospore and ascus morphology, structure of the ascal apex, ascogenous system, mode of conidiogenesis and the large subunit rRNA sequences of this group differ considerably from C. pulchella and both groups are unrelated. Thus a new genus, Tectonidula, is described with two accepted species, T. hippocrepida and T. fagi; they are separated by ascospore and ascus morphology and holoblastic-denticulate conidiogenesis from the core species of Calosphaeria. The placement of Tectonidula among perithecial ascomycetes is discussed. The relationship of Tectonidula with Barbatosphaeria and two ramichloridium-like hyphomycetous genera Rhodoveronaea and Myrmecridium is investigated. Three species formerly attributed to Ceratostomella are studied. The revision of the herbarium type specimen and fresh material of Ceratostomella ligneola revealed that it is conspecific with Ceratostomella ampullasca and Ceratostomella similis. The LSU phylogeny clearly separated C. ligneola from Ceratostomella s. str. and morphologically similar Lentomitella. On the basis of molecular sequence data and detailed comparison of morphology of asci, ascospores and ascogenous system the genus Natantiella is described for C. ligneola with C. ampullasca and C. similis as its synonyms. Natantiella produced sterile mycelium in vitro.

• MeSH
• DNA fungální genetika   izolace a purifikace   MeSH
• druhová specificita MeSH
• fylogeneze MeSH
• ribozomální DNA genetika   MeSH
• sekvenční analýza DNA MeSH
• Sordariales klasifikace   cytologie   fyziologie   MeSH
• spory hub cytologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA fungální MeSH
• ribozomální DNA MeSH

The new genus Barbatosphaeria is described for a perithecial ascomycete known as Calosphaeria barbirostris occurring on decayed wood of deciduous trees under the periderm. The fungus produces nonstromatic perithecia with hyaline, 1-septate ascospores formed in unitunicate, nonamyloid asci. Anamorphs produced in vitro belong to Sporothrix and Ramichloridium with holoblastic-denticulate conidiogenesis; conidiophores of the two types were formed in succession during the development of the colony. Phylogenetic analyses of nuLSU rDNA sequences indicate that this fungus is distinct from morphologically similar Lentomitella, tentatively placed in the Trichosphaeriales. It groups with freshwater Aquaticola and Cataractispora and terrestrial Cryptadelphia in maximum parsimony analysis; the same grouping but without Cryptadelphia was inferred from Bayesian analysis. Cultivation, morphology and phylogenetic studies of the nuLSU rDNA support the erection of a new genus for C. barbirostris.

• MeSH
• Ascomycota klasifikace   genetika   ultrastruktura   MeSH
• DNA fungální chemie   genetika   MeSH
• fylogeneze MeSH
• interferenční mikroskopie MeSH
• mikroskopie fázově kontrastní MeSH
• molekulární sekvence - údaje MeSH
• polymerázová řetězová reakce MeSH
• RNA ribozomální chemie   genetika   MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení MeSH
• terminologie jako téma MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA fungální MeSH
• RNA ribozomální MeSH