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Several Usnea species in subgenus Eumitria (Parmeliaceae, lichenized Ascomycota) have been described from East Africa in the past decades. These have been based on morphology and chemistry data while molecular studies remain very limited. In this paper we are for the first time publishing phylogenetic analyses along with morphological and chemical data for Eumitria. ‬A total of 62 new sequences of Eumitria (26 ITS, 20 nuLSU, 6 MCM7, 10 RPB1) were generated in this study. nuLSU, MCM7 and RPB1 sequences are here for the first time reported for U. baileyi. A phylogeny of subgenus Eumitria from Tanzania based on Bayesian and maximum likelihood analyses of a concatenated four-loci data set is presented, confirming the monophyly of Eumitria. Further, secondary chemistry and variation in characters, such as the pigmentation of the central axis and branch shape were investigated. Swedish International Development Cooperation Agency (SIDA) – UDSM-SIDA, Project No. 2221.

Raco/eus trichophorus gen. sp. nov. is described for a tropical sterile filamentous lichenized fungus which overgrows various crustose lichens on bark. It shares some features with Cystoco/eus and Racodium, but is unique in having non-lichenized long lateral spines. The genus, which is known from China, the Ivory Coast, and Peru, is of uncertain systematic position; on the basis of morphological similarities, however, it may be referred to "? Capnodia/es (incertae sedis)" ad interim. In addition, the nomenclature and typification of the monotypic genera Cystoco/eus and Racodium are reviewed, and lectotypes selected for the type of each. The available information on the ecology and distribution of these two genera is also summarized, and scanning electron micrographs (SEM) of all three species are presented for the first time.

Recent molecular phylogenetic analyses and morphological Studies have shown that it is necessary to revise the present morphology-based generic delineation of the lichen family Verrucariaceae in or ...

Phylogenetic relationships of the lichen genus Polyblastia and closely related taxa in the family Verrucariaceae (Verrucariales, Chaetothyriomycetidae) were studied. A total of 130 sets of sequences (nuLSU rDNA, nuITS rDNA and RPB1 region A–D), including 129 newly generated sequences, were analysed. Phylogenetic relationships were inferred using a Bayesian approach based on two datasets. A first analysis of a larger, two-locus dataset (nuLSU and RPB1) for 128 members of the Verrucariaceae, confirmed the polyphyly of Polyblastia, Thelidium, Staurothele, and Verrucaria, as currently construed. The second analysis focused on 56 Polyblastia and allied taxa, but using an additional locus (nuITS rDNA) and two closely related outgroup taxa. The latter analysis revealed strongly supported groups, such as Polyblastia s. str., the Thelidium group (a mixture of Polyblastia, Thelidium, Staurothele and Verrucaria species). The genus Sporodictyon, which is here accepted, also accommodates Sporodictyon terrestre comb. nov. Morphological features traditionally used for characterizing Polyblastia, Thelidium, Staurothele and Verrucaria, such as spore septation and colour, occurrence of hymenial photobiont, involucrellum structure, and substrate preference, were found to be only partially consistent within the strongly supported clades, and thus are not always reliable features for characterizing natural groups.

The class Eurotiomycetes (Ascomycota, Pezizomycotina) is a monophyletic group comprising two major clades of very different ascomycetous fungi: (i) the subclass Eurotiomycetidae, a clade that contains most of the fungi previously recognized as Plectomycetes because of their mostly enclosed ascomata and prototunicate asci; and (ii) the subclass Chaetothyriomycetidae, a group of fungi that produce ascomata with an opening reminiscent of those produced by Dothideomycetes or Sordariomycetes. In this paper we use phylogenetic analyses based on data available from the Assembling the Fungal Tree of Life project (AFTOL), in addition to sequences in GenBank, to outline this important group of fungi. The Eurotiomycetidae include producers of toxic and useful secondary metabolites, fermentation agents used to make food products and enzymes, xerophiles and psychrophiles, and the important genetics model Aspergillus nidulans. The Chaetothyriomycetidae include the common black yeast fungi, some of which are pathogens of humans and animals, as well as some primarily lichenized groups newly found to be phylogenetically associated with this group. The recently proposed order Mycocaliciales shows a sister relationship with Eurotiomycetes. The great majority of human pathogenic Pezizomycotina are Eurotiomycetes, particularly in Eurotiales, Onygenales and Chaetothyriales. Due to their broad importance in basic research, industry and public health, several genome projects have focused on species in Onygenales and Eurotiales.

Phylogenetic analyses based on nuLSU and mtSSU indicate that Megasporaceae is monophyletic. Aspicilia species were distributed among three main well supported groups and one group with low support that included the type species; a division of the family into five genera is proposed. The old names Circinaria and Sagedia are reintroduced for groups not including A. cinerea, the type of Aspicilia. The monotypic Megaspora is closely related to Circinaria, while Lobothallia is the sister group of the other Megasporaceae genera. Aspicilia recedens and A. farinosa are transferred to Lobothallia. Species of the 'Sphaerothallia group' are nested in Circinaria. Aspilidea is not a member of Megasporaceae but seems to be more closely related to Ochrolechiaceae. Aspilidea myrinii is neotypified, and lectotypes are designated for Aspicilia gibbosa, A. leprosescens and Lecanora gibbosula.

Lectins are carbohydrate binding proteins that are involved in many recognition events at molecular and cellular levels. Lectin-oligosaccharide interactions are generally considered to be of weak affinity, however some mushroom lectins have unusually high binding affinity towards oligosaccharides with K (d) values in the micromolar range. This would make mushroom lectins ideal candidates to study protein-carbohydrate interactions. In the present study we investigated the properties of a recombinant form of the mushroom lectin Aleuria aurantia (AAL). AAL is a fucose-binding lectin composed of two identical 312-amino acid subunits. Each subunit contains five binding sites for fucose. We found that one of the binding sites in rAAL had unusually high affinities towards fucose and fucose-containing oligosaccharides with K (d) values in the nanomolar range. This site could bind to oligosaccharides with fucose linked alpha1-2, alpha1-3 or alpha1-4, but in contrast to the other binding sites in AAL it could not bind oligosaccharides with alpha1-6 linked fucose. This binding site is not detected in native AAL (nAAL) one possible explanation may be that this site is blocked with free fucose in nAAL. Recombinant AAL was produced in E. coli as a His-tagged protein, and purified in a one-step procedure. The resulting protein was analyzed by electrophoresis, enzyme-linked lectin assay and circular dichroism spectroscopy, and compared to nAAL. Binding properties were measured using tryptophan fluorescence and surface plasmon resonance. Removal of the His-tag did not alter the binding properties of recombinant AAL in the enzyme-linked lectin assay. Our study forms a basis for understanding the AAL-oligosaccharide interaction and for using molecular techniques to design lectins with novel specificities and high binding affinities towards oligosaccharides.

The molecular phylogeny of the lichen genus Lecania was investigated using nucleotide sequences from the mt-SSU rRNA, the ITS region of the nu-rDNA, and the RNA polymerase II second largest subunit. Forty-six species representing Lecania and other genera likely to influence the phylogeny were included in the study. Phylogenetic reconstructions were carried out using Bayesian inference, ML, and MP approaches. Lecania, as traditionally circumscribed, is not a monophyletic genus. However, a monophyletic group containing a large number of Lecania species, including the type species L. fuscella, was discovered in the analysis, and recognition of Lecania sensu stricto is suggested. L. baeomma, L. glauca, L. gerlachei, L. brialmontii, L. racovitzae, L. hyalina (alias Biatora globulosa), L. chlorotiza, L. naegelii, and L. furfuracea do not belong in Lecania s. str., although the latter two are closely related to Lecania s. str. Representatives of the genus Bilimbia form a well-supported group, as does the 'Thamnolecania' group containing the Antarctic 'Lecania' species, L. gerlachei, L. brialmontii, and L. racovitzae. An alternative to recognizing these two genera would be a wider circumscription of Bilimbia to include the 'Thamnolecania' group as well as affiliated taxa.

The two morphologically similar truffles Tuber aestivum and T. uncinatum have caused confusion because T. uncinatum is regarded by different authors, as either a distinct species, variety, subspecies, or synonym of T. aestivum. A clarification of the relationship between the two truffles would help both conservation biology and cultivation. We aimed both to test the reliability of the only quantitative morphological character used to distinguish the two taxa, i.e. the height of the spore reticulum, and to compare sequences of the ribosomal DNA (rDNA) internal transcribed spacer (ITS) region. Our study included 117 fruit bodies of T. aestivum and T. uncinatum, originating from eight European countries. The results showed that the spore reticulum height is not diagnostic. The phylogenetic analysis of ITS sequences from 81 fruit bodies and an additional 32 sequences from GenBank showed that T. aestivum and T. uncinatum were intermingled in one highly supported (100% bootstrap) monophyletic clade, separate from its sister species Tuber mesentericum. We conclude that T. aestivum and T. uncinatum are synonyms and the species should be named T. aestivum, as the oldest name has priority. For traders, T. aestivum syn. T. uncinatum should be used until conformity has been reached.

Small subunit ribosomal DNA has been sequenced from seven members of the ascomycete order Caliciales s.l. (Calicium adspersum, Cyphelium inquinans, Texosporium sancti-jacobi, and Thelomma mammosum (Caliciaceae), Chaenothecopsis savonica and Stenocybe pullatula (Mycocaliciaceae), and Sphinctrina turbinata (Sphinctrinaceae)), included in a matrix of 58 homologous ascomycete sequences and analysed with maximum parsimony analysis. The result shows the Caliciaceae to be a strongly supported monophyletic group within the Lecanorales s.l., although the jackknife support for a monophyletic Lecanorales is low. Mycocaliciaceae and Sphinctrinaceae form a well-supported monophyletic group, grouping with representatives of Eurotiales and Onygenales. This larger group is the sister group to Lecanorales, but the support for this sister-group relationship and the monophyly of the group consisting of Mycocaliciaceae–Sphinctrinaceae and Eurotiales–Onygenales is low. The evolution of the prototunicate ascus is discussed, and it is concluded that there is neither any evidence for a monophyletic Caliciales s.l., nor for the suggested group "Euascomycetideae" sensu Tehler, with the prototunicate Caliciales being the sister group to the rest of the true ascomycetes. Prototunicate asci are shown to have reappeared at least four times in the evolution of the ascomycetes. Key words: Ascomycetes, lichens, molecular evolution, phylogeny, ribosomal DNA, 18S rDNA.