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PubMed2006

Phylogenetic utility of protein (RPB2, beta-tubulin) and ribosomal (LSU, SSU) gene sequences in the systematics of Sordariomycetes (Ascomycota, Fungi).

The Sordariomycetes is an important group of fungi whose taxonomic relationships and classification is obscure. There is presently no multi-gene molecular phylogeny that addresses evolutionary relationships among different classes and orders. In this study, phylogenetic analyses with a broad taxon sampling of the Sordariomycetes were conducted to evaluate the utility of four gene regions (LSU rDNA, SSU rDNA, beta-tubulin and RPB2) for inferring evolutionary relationships at different taxonomic ranks. Single and multi-gene genealogies inferred from Bayesian and Maximum Parsimony analyses were compared in individual and combined datasets. At the subclass level, SSU rDNA phylogenies demonstrate their utility as a marker to infer phylogenetic relationships at higher levels. All analyses with SSU rDNA alone, combined LSU rDNA and SSU rDNA, and the combined 28 S rDNA, SSU rDNA and RPB2 datasets resulted in three subclasses: Hypocreomycetidae, Sordariomycetidae and Xylariomycetidae, which correspond well to established morphological classification schemes. At the ordinal level, the best resolved phylogeny was obtained from the combined LSU rDNA and SSU rDNA datasets. Individually, the RPB2 gene dataset resulted in significantly higher number of parsimony informative characters. Our results supported the recent separation of Boliniaceae, Chaetosphaeriaceae and Coniochaetaceae from Sordariales and placement of Coronophorales in Hypocreomycetidae. Microascales was found to be paraphyletic and Ceratocystis is phylogenetically associated to Faurelina, while Microascus and Petriella formed another clade and basal to other members of Halosphaeriales. In addition, the order Lulworthiales does not appear to fit in any of the three subclasses. Congruence between morphological and molecular classification schemes is discussed.

Ascomycota↗

PubMed2005

Known and two new species of Rhytisma (Rhytismatales, Ascomycota) from China.

Three species of Rhytisma are described based on recently collected specimens from the Anhui province, China. Rhytisma anhuiense is a new species causing a serious tar spot disease on Rhododendron simsii. Rhytisma yuexiense is a new species, which develops its stromata only on fallen leaves of Rhododendron ovatum. Rhytisma himalense on Ilex fargesii is a known species and probably widely distributed in China. Including the two new species, 11 species of Rhytisma are known from China which are presented in a key.

Ascomycota↗

PubMed2006

Molecular phylogeny of Acarosporaceae (Ascomycota) with focus on the proposed genus Polysporinopsis.

The molecular phylogeny of Acarosporaceae with a focus on the recently proposed genus Polysporinopsis was investigated using maximum parsimony and Bayesian analyses, using nuITS-LSU and mtSSU rDNA sequence datasets. A well-supported monophyletic clade corresponding to Acarospora (including the type species A. schleicheri, A. fuscata, A. nitrophila, A. rugulosa, A. bullata, A. sinopica, A molybdina and A. peliscypha) was present in all analyses. Acarospora as currently delimited is not monophyletic; neither A. smaragdula nor A. badiofusca belongs to the genus in the restricted sense. Polysporinopsis, which comprises three species previously classified in Acarospora (P. sinopica-type species, P. smaragdula, and P. rugulosa) is not a monophyletic group separate from Acarospora s. str. Acarospora sinopica and A. smaragdula are not closely related; A. sinopica belongs to Acarospora s. str., but A. smaragdula is one of the most basal taxa currently known in Acarosporaceae.

Ascomycota↗

PubMed2006

Phylogenetic relationships of coprophilous Pleosporales (Dothideomycetes, Ascomycota), and the classification of some bitunicate taxa of unknown position.

The purpose of this study was to investigate the natural relationships within the large bitunicate order Pleosporales, with special focus on the coprophilous families Delitschiaceae, Phaeotrichaceae and Sporormiaceae. Parsimony and Bayesian analyses were performed using nSSU, nLSU and mtSSU rDNA sequence data. We also investigated the placement of a number of taxa with uncertain position. Our results showed that Pleosporales, including Delitschiaceae, Sporormiaceae, Zopfiaceae and Testudinaceae, form a monophyletic group with strong support. Although Delitschiaceae has been considered a synonym of Sporormiaceae, the two families do not form one monophyletic group. Similarly, Zopfiaceae and Testudinaceae should be retained as separate families as they did not group together or with Phaeotrichaceae or Sporormiaceae. Zopfiaceae and Delitchiaceae did group together, but without significant support. Eremodothis angulata (currently in Testudinaceae) is closely related to Westerdykella in Sporormiaceae. Phaeotrichaceae and Venturiaceae formed a group with strong BS support on a branch outside Pleosporales, but an alternative topology including Phaeotrichaceae and Venturiaceae within Pleosporales could not be rejected. All taxa in the present study that were placed with uncertain position in Dothideomycetes/Chaetothyriomycetes in the current classification by Eriksson, grouped within the monophyletic Dothideomycetes.

Ascomycota↗

PubMed2006

Ophiostoma arduennense sp. nov. (Ophiostomatales, Ascomycota) from Fagus sylvatica in southern Belgium.

Ophiostoma arduennense sp. nov. is described from several cultures isolated from Fagus sylvatica in southern Belgium. The species is mainly characterized by globose perithecia with small button-like bases ornamented with brown hyphal hairs of variable length and, long cylindrical necks ending in ostiolate hyphae. It is homothallic with small reniform ascospores and no apparent anamorph. It is closely associated with the ambrosia beetles Xyloterus domesticus and X. signatus. Its phylogenetic relationships within Ophiostoma are discussed and the species is compared with other Ophiostoma species associated with European beech or other broad-leaved trees in Europe, especially species of the O. quercus-O. piceae complex. The species is responsible for a dark brown staining of the sapwood and its role in the decline of beech in Southern Belgium is also discussed.

Animals↗

PubMed2006

Phylogeny and phenotypic variation in the lichen family Graphidaceae (Ostropomycetidae, Ascomycota).

A phylogenetic study of the lichen family Graphidaceae is presented. Most genera of the family, as well as selected representatives of the closely related Thelotremataceae, are included. The results of the Bayesian analysis of combined mt SSU and nuLSU rDNA sequence data were compared with recently introduced concepts of genera. Species of Fissurina and Dyplolabia form a monophyletic group in an unresolved sister-group relationship to other members of Graphidaceae and Thelotremataceae. The family Graphidaceae as currently circumscribed is paraphyletic and we suggest that the name Graphidaceae is used in a broader sense to include members of Thelotremataceae. The concepts of Glyphis, Phaeographis and Platygramme are confirmed by molecular data. Surprisingly, Graphis species are found in two distinct clades, which can only partly be explained by morphology. Hemithecium as recently circumscribed is polyphyletic: H. implicatum, with hyaline spores groups within the Graphis scripta clade, whereas a second Hemithecium species, representing subgenus Leucogramma with brown spores, forms a well-supported clade with other brown-spored species such as 'Sarcographina'lyphiza, Leiorreuma hypomelaenum and Sarcographa ramificans. The evolutionary pattern of morphological characters of the ascomata such as exciple carbonization, paraphyses types, and ascospore characters (colour, septation, and Lugols reaction) are critically discussed.

Ascomycota↗

PubMed2006

Molecular phylogeny supports a Northern Hemisphere origin of Golovinomyces (Ascomycota: Erysiphales).

Golovinomyces is a strictly herb-parasitic genus in the Erysiphaceae. Host-parasite co-speciation was reported recently between the genus Golovinomyces and Asteraceae from molecular phylogenetic analyses. The Asteraceae originated in South America and latterly expanded their geographic distribution into the Northern Hemisphere. If the co-speciation between Golovinomyces and Asteraceae originated in South America, the geographic origin of Golovinomyces could be assumed to be South America. To address this question, Golovinomyces species from hosts of the tribe Mutisieae, an asteraceous tribe endemic to South America, were collected and the ITS and 28S rDNA regions sequenced. Results indicate that Oidium mutisiae and Golovinomyces leuceriae isolated from the Mutisieae do not belong at the base of the Golovinomyces tree. Instead, they are situated separately within two different clades of Golovinomyces isolates from the Northern Hemisphere. Therefore, the tribe Mutisieae is not the most early host of Golovinomyces. Present results suggest that Golovinomyces originated in the Northern Hemisphere, and not in South America. The new species Oidium reginae for the previous O. mutisiae on Mutisia decurrens is proposed.

Argentina↗

PubMed2005

Diversity of non-reducing polyketide synthase genes in the Pertusariales (lichenized Ascomycota): a phylogenetic perspective.

Lichenized fungi synthesize a great variety of secondary metabolites. These are typically crystalline compounds, which are deposited extracellularly on the fungal hyphae. While we know a lot about the chemical properties and structures of these substances, we have very little information on the molecular background of their biosynthesis. In the current study we analyze the diversity of non-reducing polyketide synthase (PKS) genes in members of the lichenized Pertusariales. This order primarily contains fully oxidized secondary metabolites from different substance classes, and is chemically and phylogenetically well studied. Using a degenerate primer approach with subsequent cloning we detected up to five non-reducing PKS sequences in a single PCR product. Eighty-five new KS sequence fragments were obtained for this study. Analysis of the 157 currently available fungal KS sequence fragments in a Bayesian phylogenetic framework revealed 18 highly supported clades that included only lichenized taxa, only non-lichenized taxa, or both. Some Pertusarialean groupings of PKS sequences corresponded partly to phylogenetic groupings based on ribosomal DNA. This is reasonable, because a correlation between well-supported phylogenetic lineages and the occurrence of secondary metabolites in the Pertusariales has been observed before. However, no clear linkage was found between the PKS genes analyzed and the ability to produce a particular secondary substance. Several PKS clades did not reveal obvious patterns of secondary compound distribution or phylogenetic association. Compared with earlier phylogenetic analyses of KS sequences the increased sampling in the current study allowed us to detect many new groupings within the fungal non-reducing PKSs.

Ascomycota↗

PubMed2005

Multi-gene phylogenies indicate ascomal wall morphology is a better predictor of phylogenetic relationships than ascospore morphology in the Sordariales (Ascomycota, Fungi).

Ascospore characters have commonly been used for distinguishing ascomycete taxa, while ascomal wall characters have received little attention. Although taxa in the Sordariales possess a wide range of variation in their ascomal walls and ascospores, genera have traditionally been delimited based on differences in their ascospore morphology. Phylogenetic relationships of multiple representatives from each of several genera representing the range in ascomal wall and ascospore morphologies in the Sordariales were estimated using partial nuclear DNA sequences from the 28S ribosomal large subunit (LSU), beta-tubulin, and ribosomal polymerase II subunit 2 (RPB2) genes. These genes also were compared for their utility in predicting phylogenetic relationships in this group of fungi. Maximum parsimony and Bayesian analyses conducted on separate and combined data sets indicate that ascospore morphology is extremely homoplastic and not useful for delimiting genera. Genera represented by more than one species were paraphyletic or polyphyletic in nearly all analyses; 17 species of Cercophora segregated into at least nine different clades, while six species of Podospora occurred in five clades in the LSU tree. However, taxa with similar ascomal wall morphologies clustered in five well-supported clades suggesting that ascomal wall morphology is a better indicator of generic relationships in certain clades in the Sordariales. The RPB2 gene possessed over twice the number of parsimony-informative characters than either the LSU or beta-tubulin gene and consequently, provided the most support for the greatest number of clades.

Ascomycota↗

PubMed2006

Major clades of parmelioid lichens (Parmeliaceae, Ascomycota) and the evolution of their morphological and chemical diversity.

Parmelioid lichens comprise about 1500 species and have a worldwide distribution. Numerous species are widely distributed and well known, including important bioindicators for atmospheric pollution. The phylogeny and classification of parmelioid lichens has been a matter of debate for several decades. Previous studies using molecular data have helped to establish hypotheses of the phylogeny of certain clades within this group. In this study, we infer the phylogeny of major clades of parmelioid lichens using DNA sequence data from two nuclear loci and one mitochondrial locus from 145 specimens (117 species) that represent the morphological and chemical diversity in these taxa. Parmelioid lichens are not monophyletic; however, a core group is strongly supported as monophyletic, excluding Arctoparmelia and Melanelia s. str., and including Parmeliopsis and Parmelaria. Within this group, seven well-supported clades are found, but the relationships among them remain unresolved. Stochastic mapping on a MC/MCMC tree sampling was employed to infer the evolution of two morphological and two chemical traits believed to be important for the evolutionary success of these lichens, and have also been used as major characters for classification. The results suggest that these characters have been gained and lost multiple times during the diversification of parmelioid lichens.

Ascomycota↗

PubMed2001

[Ultrastructure of Weddellomyces epicallopisma (Dothideales, Dacampiaceae, Ascomycota), especially of its ascospores].

An ultrastructural study of Weddellomyces epicallopisma (ascomata wall, asci, ascospores and vegetative hyphae), the first done on the family Dacampiaceae, confirms most of the observations made in light microscopy. Moreover it shows that ascospores are provided with an endospore (not visible in light microscope) and that the structure of the ascospore septum is more complex. The similarity of the wall structure between the ascospore and the hyphoid appendages, developed on the upper part of the ascoma, is emphasized.

Ascomycota↗

PubMed2003

Viegasella and Mintera, two new genera of Parmulariaceae (Ascomycota), with notes on the species referred to Schneepia.

Two species previously accommodated in the genus Schneepia, S. pulchella and S. reticulata, are shown to belong to distinct new genera, described here as Viegasella and Mintera respectively. The new taxa are compared with Parmularia (of which Schneepia is confirmed as a synonym) and Symphaeophyma. Features of internal and external stromata, haustoria and stromata are emphasized as important characters for generic delimitation in the Parmulariaceae. The disposition of the remaining species assigned to Schneepia is discussed.

Ascomycota↗

PubMed2003

Molecular phylogenetic study at the generic boundary between the lichen-forming fungi Caloplaca and Xanthoria (Ascomycota, Teloschistaceae).

A molecular phylogenetic analysis of rDNA was performed for seven Caloplaca, seven Xanthoria, one Fulgensia and five outgroup species. Phylogenetic hypotheses are constructed based on nuclear small and large subunit rDNA, separately and in combination. Three strongly supported major monophyletic groups were revealed within the Teloschistaceae. One group represents the Xanthoria fallax-group. The second group includes three subgroups: (1) X. parietina and X. elegans; (2) basal placodioid Caloplaca species followed by speciations leading to X. polycarpa and X. candelaria; and (3) a mixture of placodioid and endolithic Caloplaca species. The third main monophyletic group represents a heterogeneous assemblage of Caloplaca and Fulgensia species with a drastically different metabolite content. We report here that the two genera Caloplaca and Xanthoria, as well as the subgenus Gasparrinia, are all polyphyletic. The taxonomic significance of thallus morphology in Teloschistaceae and the current delimitation of the genus Xanthoria is discussed in light of these results.

Ascomycota↗

PubMed2004

Mycosphaerella punctiformis revisited: morphology, phylogeny, and epitypification of the type species of the genus Mycosphaerella (Dothideales, Ascomycota).

Mycosphaerella punctiformis, the type species of the genus Mycosphaerella, is epitypified by material collected on Quercus robur in The Netherlands. The teleomorph is described in planta, and the Ramularia anamorph, for which the new name R. endophylla is proposed, and the Asteromella spermatial state are characterized in vitro. Sequence data of the nuclear ribosomal DNA are presented and analyzed together with other Mycosphaerella spp. with Ramularia and several other anamorphs. Several strains originating from Quercus, Acer and Tilia showed diverging ITS sequences, indicating that the M. punctiformis complex may comprise more than a single phylogenetic species, but this could not be confirmed by the analysis of our dataset. An endophytic phase is established for the first time in the life-cycle of M. punctiformis, as the species was repeatedly isolated from surface sterilized green healthy leaves of Quercus robur in summer at the epitype locality.

Ascomycota↗

PubMed2005

Disintegration of the Micareaceae (lichenized Ascomycota): a molecular phylogeny based on mitochondrial rDNA sequences.

The phylogeny of the family Micareaceae and the genus Micarea was studied using mitochondrial small subunit ribosomal DNA sequences. Phylogenetic reconstructions were performed using Bayesian MCMC tree sampling and a maximum likelihood approach. The Micareaceae in its current sense is highly heterogeneous, and Helocarpon, Psilolechia, and Scutula, all thought to be close relatives of Micarea, are shown to be only distantly related. The genus Micarea is paraphyletic unless the entire Pilocarpaceae and Ectolechiaceae are included, as also indicated by an expected likelihood weights test. It is suggested that the Micareaceae is reduced to synonymy with the Pilocarpaceae, which also includes the Ectolechiaceae, and that Micarea may have to be divided into a series of smaller genera in the future. Micarea species with a 'non-micareoid' photobiont group with Psora and the Ramalinaceae, whereas Micarea intrusa appears to belong in Scoliciosporum. Three species fall inside the paraphyletic Micarea: Szczawinskia tsugae, Catillaria contristans, and Fellhaneropsis vezdae. Tropical foliicolous taxa are nested within groups of mainly temperate and arctic-alpine distribution. A 'micareoid' photobiont appears to be plesiomorphic in the Pilocarpaceae but has been lost a few times.

Ascomycota↗

PubMed2005

Molecular evidence supports the distinction between Xanthoria parietina and X. aureola (Teloschistaceae, lichenized Ascomycota).

This study aims to clarify taxonomic relationships within the current concept of Xanthoria parietina in northern Europe. For comparison, X. calcicola was also included in the study. Morphological as well as molecular data were utilized. Morphology indicated the presence of three species, Xanthoria parietina, X. calcicola, and X. aureola, the latter of which is resurrected here from synonymy. The most important separating characters involve colour and thickness of the thallus, lobe width, morphology of laminar structures, and the texture of the upper surface. X. aureola, as recognized here, mostly occurs on seashore rocks. Part of the IGS region as well as the complete ITS were sequenced in 70 individual thalli representing ten geographical regions in Europe. In total, 19 different IGS haplotypes and 20 different ITS haplotypes were present in the data set. Owing to indications of possible recombination between the IGS and the ITS, the two data sets were analyzed separately. Haplotype networks were estimated, both of which indicate that X. parietina is distinct from X. aureola and X. calcicola. In our sample, the two latter do not share haplotypes, but are only separated by a few mutational steps.

Ascomycota↗

PubMed2004

Corticolous species of Trichothelium (Ascomycota: Porinaceae).

A survey of corticolous crustose lichen collections in connection with the Flora Neotropica project revealed a number of undescribed species of Trichothelium. While a few typically foliicolous taxa may occasionally be found on bark, five species seem to be exclusively corticolous, all with a Trentepohlia photobiont. Three of them are new species: T. angustisporum, T. caudatum, and T. kalbii spp. nov. A key is provided to all five corticolous species, accompanied by data on their distribution and ecology. A considerable range extension is reported for T. horridulum, with new collections from Costa Rica and north-eastern Brazil.

Ascomycota↗

PubMed2004

Molecular phylogeny of the genus Physconia (Ascomycota, Lecanorales) inferred from a Bayesian analysis of nuclear ITS rDNA sequences.

A Bayesian analysis of nuclear ribosomal DNA internal transcribed spacer (ITS) sequences was used to infer phylogenetic relationships of 14 Physconia species. The analysis supports the monophyly of the genus. Three well supported clades can be distinguished within Physconia: the series griseae, venustae and pulverulentae. The relationships of these clades, however, is not resolved with confidence. Cortical characters are re-evaluated on the basis of the phylogenetic hypothesis. Anatomical features of the upper cortex are only diagnostic above the species level for two special forms of two-layered cortices, while morphological characters, such as lower surface and rhizine-type are characteristic for distinct clades. P. venusta and P. perisidiosa are not separated in this analysis, but populations of P. muscigena, and European and North American samples of P. americana are clearly distinct and the monophyly of both P. americana and P. muscigena s. lat. is rejected on the basis of a Bayesian hypothesis testing.

Ascomycota↗