Fungi in hair roots of Vaccinium spp. (Ericaceae) growing on decomposing wood: colonization patterns, identity, and in vitro symbiotic potential.

Most of our knowledge on the ericoid mycorrhizal (ErM) symbiosis comes from temperate heathlands characterized by acidic peaty soils and many experiments with a few ascomycetous fungi. However, ericaceous plants thrive in many other ecosystems and in temperate coniferous forests, their seedlings often prosper on decomposing wood. While wood is typically exploited by basidiomycetous ectomycorrhizal (EcM) and saprobic fungi, the role of ErM fungi (ErMF) is much less clear. We explored the cultivable mycobiota of surface sterilized hair roots of Vaccinium spp. growing on decomposing wood in two coniferous forests in Mid-Norway (Scandinavia) and Northern Bohemia (Central Europe). Obtained isolates were identified using molecular tools and their symbiotic potential was tested in vitro. While the detected community lacked the archetypal ErMF Hyaloscypha hepaticicola and the incidence of dark septate endophytes and EcM fungi was negligible, it comprised other frequent asexual ascomycetous ErMF, namely H. variabilis and Oidiodendron maius, together with several isolates displaying affinities to sexual saprobic H. daedaleae and H. fuckelii. Ascomycete-suppressing media revealed representatives of the saprobic basidiomycetous genera Coprinellus, Gymnopilus, Mycena (Agaricales), and Hypochnicium (Polyporales). In the resyntheses, the tested basidiomycetes occasionally penetrated the rhizodermal cells of their hosts but never formed ericoid mycorrhizae and in many cases overgrew and killed the inoculated seedlings. In contrast, a representative of the H. daedaleae/H. fuckelii-related isolates repeatedly formed what morphologically appears as the ErM symbiosis and supported host's growth. In conclusion, while basidiomycetous saprobic fungi have a potential to colonize healthy-looking ericaceous hair roots, the mode(-s) of their functioning remain obscure. For the first time, a lineage in Hyaloscypha s. str. (corresponding to the former Hymenoscyphus ericae aggregate) where sexual saprobes are intermingled with root symbionts has been revealed, shedding new light on the ecology and evolution of these prominent ascomycetous ErMF.

Phylogenetic Reassessment, Taxonomy, and Biogeography of Codinaea and Similar Fungi.

The genus Codinaea is a phialidic, dematiaceous hyphomycete known for its intriguing morphology and turbulent taxonomic history. This polyphasic study represents a new, comprehensive view on the taxonomy, systematics, and biogeography of Codinaea and its relatives. Phylogenetic analyses of three nuclear loci confirmed that Codinaea is polyphyletic. The generic concept was emended; it includes four morphotypes that contribute to its morphological complexity. Ancestral inference showed that the evolution of some traits is correlated and that these traits previously used to delimit taxa at the generic level occur in species that were shown to be congeneric. Five lineages of Codinaea-like fungi were recognized and introduced as new genera: Codinaeella, Nimesporella, Stilbochaeta, Tainosphaeriella, and Xyladelphia. Dual DNA barcoding facilitated identification at the species level. Codinaea and its segregates thrive on decaying plants, rarely occurring as endophytes or plant pathogens. Environmental ITS sequences indicate that they are common in bulk soil. The geographic distribution found using GlobalFungi database was consistent with known data. Most species are distributed in either the Holarctic realm or tropical geographic regions. The ancestral climatic zone was temperate, followed by transitions to the tropics; these fungi evolved primarily in Eurasia and Americas, with subsequent transitions to Africa and Australasia.

Reflections on Menisporopsis, Multiguttulispora and Tainosphaeria Using Molecular and Morphological Data.

The genera Menisporopsis, Multiguttulispora and Tainosphaeria (Chaetosphaeriaceae) are saprobes inhabiting decaying plant material. This study is based on an integrated morpho-molecular characterisation to assess their generic concepts and explore phylogenetic relationships. Menisporopsis is revealed as polyphyletic, and species with 1-septate conidia and synnemata growing unilaterally along the seta are placed in the new segregate genus Arcuatospora. Codinaea dimorpha and C. triseptata are shown to be congeneric with Multiguttulispora sympodialis, the type species. Two new combinations are proposed: M. sympodialis is found conspecific with M. dimorpha. The Tainosphaeria complex is resolved into three genera. We found that the morphological separation of three groups within the genus is consistent with phylogenetic relationships. Tainosphaeria s. str. is accepted with five species. Tainosphaeria aseptata and T. lunata are transferred to the newly erected Phialoturbella, whereas T. obclavata is revealed as conspecific with Phialogeniculata guadalcanalensis, reducing it to a synonym. A new genus Flectospora is erected for a chloridium-like fungus nested in the Tainosphaeria clade. Based on molecular evidence, we show that asymmetrical, scolecosporous ascospores are a unique teleomorphic characteristic among family members. Therefore, we propose new combinations for Chaetosphaeria hispida in Paragaeumannomyces and Ch. spinosa in the new genus Ericiosphaeria, both exhibiting this rare morphotype.

Phylogeny, Global Biogeography and Pleomorphism of Zanclospora.

Zanclospora (Chaetosphaeriaceae) is a neglected, phialidic dematiaceous hyphomycete with striking phenotypic heterogeneity among its species. Little is known about its global biogeography due to its extreme scarcity and lack of records verified by molecular data. Phylogenetic analyses of six nuclear loci, supported by phenotypic data, revealed Zanclospora as highly polyphyletic, with species distributed among three distantly related lineages in Sordariomycetes. Zanclospora is a pleomorphic genus with multiple anamorphic stages, of which phaeostalagmus-like and stanjehughesia-like are newly discovered. The associated teleomorphs were previously classified in Chaetosphaeria. The generic concept is emended, and 17 species are accepted, 12 of which have been verified with DNA sequence data. Zanclospora thrives on decaying plant matter, but it also occurs in soil or as root endophytes. Its global diversity is inferred from metabarcoding data and published records based on field observations. Phylogenies of the environmental ITS1 and ITS2 sequences derived from soil, dead wood and root samples revealed seven and 15 phylotypes. The field records verified by DNA data indicate two main diversity centres in Australasia and Caribbean/Central America. In addition, environmental ITS data have shown that Southeast Asia represents a third hotspot of Zanclospora diversity. Our data confirm that Zanclospora is a rare genus.

From the Tunnels into the Treetops: New Lineages of Black Yeasts from Biofilm in the Stockholm Metro System and Their Relatives among Ant-Associated Fungi in the Chaetothyriales.

Rock-inhabiting fungi harbour species-rich, poorly differentiated, extremophilic taxa of polyphyletic origin. Their closest relatives are often well-known species from various biotopes with significant pathogenic potential. Speleothems represent a unique rock-dwelling habitat, whose mycobiota are largely unexplored. Isolation of fungi from speleothem biofilm covering bare granite walls in the Kungsträdgården metro station in Stockholm yielded axenic cultures of two distinct black yeast morphotypes. Phylogenetic analyses of DNA sequences from six nuclear loci, ITS, nuc18S and nuc28S rDNA, rpb1, rpb2 and ß-tubulin, support their placement in the Chaetothyriales (Ascomycota). They are described as a new genus Bacillicladium with the type species B. lobatum, and a new species Bradymyces graniticola. Bacillicladium is distantly related to the known five chaetothyrialean families and is unique in the Chaetothyriales by variable morphology showing hyphal, meristematic and yeast-like growth in vitro. The nearest relatives of Bacillicladium are recruited among fungi isolated from cardboard-like construction material produced by arboricolous non-attine ants. Their sister relationship is weakly supported by the Maximum likelihood analysis, but strongly supported by Bayesian inference. The genus Bradymyces is placed amidst members of the Trichomeriaceae and is ecologically undefined; it includes an opportunistic animal pathogen while two other species inhabit rock surfaces. ITS rDNA sequences of three species accepted in Bradymyces and other undescribed species and environmental samples were subjected to phylogenetic analysis and in-depth comparative analysis of ITS1 and ITS2 secondary structures in order to study their intraspecific variability. Compensatory base change criterion in the ITS2 secondary structure supported delimitation of species in Bradymyces, which manifest a limited number of phenotypic features useful for species recognition. The role of fungi in the speleothem biofilm and relationships of Bacillicladium and Bradymyces with other members of the Chaetothyriales are discussed.

Cirrosporium novae-zelandiae, an enigmatic coelomycete with meristem arthroconidia, with ancestors in the Eurotiomycetes.

A culture of Cirrosporium novae-zelandiae, the type species of a distinctive, monotypic coelomycete genus, was isolated from a specimen collected near the holotype locality in New Zealand. Light microscopic and environmental scanning electron microscopic observations confirm the details of the unusual meristem arthric conidium ontogeny presented in the protolog. For phylogenetic analysis, a dataset of 122 species representing nine classes of euascomycetes was assembled including sequences from nuclear small and large subunits (nc18S, nc28S) and mitochondrial small subunit (mr16S) ribosomal RNA and the largest and second largest subunits of RNA polymerase II (RPB1, RPB2). A five-gene phylogeny suggests that the fungus is phylogenetically related to the Eurotiomycetes. It sits alone on a long branch as a sister to the Mycocaliciales of the Mycocaliciomycetidae. Cirrosporium exhibits several morphological characters similar to those of members of the Mycocaliciales; however, the paucity of known anamorphs in this order does not offer any further clarification on possible relationships. It is clear that the rare and broadly distributed meristem arthric ontogenetic pattern is polyphyletic, occurring in widely separate groups of anamorphs of both the Ascomycota and Basidiomycota.

New fungal genera, Tectonidula gen. nov. for Calosphaeria-like fungi with holoblastic-denticulate conidiogenesis and Natantiella gen. nov. for three species segregated from Ceratostomella.

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.

Bellojisia, a new sordariaceous genus for Jobellisia rhynchostoma and a description of Jobellisiaceae fam. nov.

The phylogenetic analyses of partial nucLSU rDNA sequence data of three Jobellisia species indicate that J. rhynchostoma is distinct from the core species of Jobellisia. Jobellisia luteola, the type species of the genus, and J. fraterna reside as a strongly supported monophyletic clade in a basal position in a grouping containing the Diaporthales, the Calosphaeriales and the Togniniaceae, while all phylogenies confirm the placement of J. rhynchostoma within the Sordariales. The new family Jobellisiaceae (incertae sedis) is described for Jobellisia. A new perithecial ascomycete genus, Bellojisia (Lasiosphaeriaceae, Sordariales), is introduced for J. rhynchostoma. The fungus produces nonstromatic, long-necked perithecia with a superficial to semi-immersed pyriform venter and carbonaceous three-layered perithecial wall, 1-septate, hyaline, later brown, reniform to navicular ascospores with a polar germ pore formed in unitunicate asci. The fungus was not observed to produce a conidial anamorph in vitro. Both morphological and molecular data suggest Corylomyces selenosporus of the Sordariales is the closest relative of J. rhynchostoma. The other relatives of Bellojisia (viz. Cercophora, Lasiosphaeria and Podospora) recruit from the Lasiosphaeriaceae (Sordariales). Cercophora and Podospora are shown as polyphyletic within the Sordariales, which is in agreement with previous molecular studies.

Romellia is congeneric with Togninia, and description of Conidiotheca gen. nov. for one species of this genus with polysporous asci.

During a continued survey of fungi accommodated in the Calosphaeriales, we observed that the genus Romellia is morphologically heterogeneous. Historically, four species were placed in the genus. Romellia was introduced for taxa with globose, dark, superficial, papillate perithecia, a paraphysate centrum, and octosporous asci containing eight allantoid, hyaline ascospores. The type species, R. vibratilis, was revised in our study, and its freshly collected material was cultured. The anamorph obtained in vitro matches the generic concept of the hyphomycete genus Phaeoacremonium, the anamorph of Togninia. The phylogenies inferred from newly obtained sequences of LSU rDNA, beta-tubulin, and actin of R. vibratilis revealed that the species is congeneric with Togninia (Togniniaceae) and represents a good species. Revision of type and herbarium material of other Romellia species confirmed they are not congeneric with Togninia. Romellia tympanoides possesses immersed, subglobose perithecia with sessile asci containing eight ascospores, which during maturation produce ascoconidia filling the entire ascus. This maturation process represents a new kind of apparent polyspory known in the ascomycetes. We introduce a new genus, Conidiotheca, and a new combination for R. tympanoides. The species is compared with the genera Barrina and Tympanis. The relationships of two other Romellia species, R. ambigua and R. cornina, lie with Wegelina and Jattaea of the Calosphaeriales.

Chaetosphaeria tortuosa, the newly discovered teleomorph of Menispora tortuosa, with a key to known Menispora species.

Chaetosphaeria tortuosa is described as the newly discovered teleomorph of Menispora tortuosa, based on specimens from Canada and the Czech Republic, and single spore isolations from both morphs. The fungus produces superficial, more or less globose, papillate, dark brown to black smooth perithecia (200-)220-250 x (220-)230-260 microm. The asci are unitunicate, 8-spored, cylindrical-fusiform, (110-)120-133(-145) x 12-14 with a distinct apical, nonamyloid annulus 1-1.5 microm high, 3.5-4 microm wide. The ascospores are fusiform, 19-24 x 5-6 microm, hyaline, 3-septate, smooth, and 2-seriate in the ascus. The morphology of the teleomorph and anamorph are similar to that of C. ovoidea (anamorph: M. glauca), differing in dimensions of asci and ascospores, and in the disposition and morphology of the phialides of the anamorphs. The generic concept and phylogeny of Menispora is briefly discussed, and a key to the 11 species currently accepted in the genus is provided.