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The genus Lecidea Ach. sensu lato (sensu Zahlbruckner) includes almost 1200 species, out of which only 100 species represent Lecidea sensu stricto (sensu Hertel). The systematic position of the remaining species is mostly unsettled but anticipated to represent several unrelated lineages within Lecanoromycetes. This study attempts to elucidate the phylogenetic placement of members of this heterogeneous group of lichen-forming fungi and to improve the classification and phylogeny of Lecanoromycetes. Twenty-five taxa of Lecidea sensu lato and 22 putatively allied species were studied in a broad selection of 268 taxa, representing 48 families of Lecanoromycetes. Six loci, including four ribosomal and two protein-coding genes for 315- and 209-OTU datasets were subjected to maximum likelihood and Bayesian analyses. The resulting well supported phylogenetic relationships within Lecanoromycetes are in agreement with published phylogenies, but the addition of new taxa revealed putative rearrangements of several families (e.g. Catillariaceae, Lecanoraceae, Lecideaceae, Megalariaceae, Pilocarpaceae and Ramalinaceae). As expected, species of Lecidea sensu lato and putatively related taxa are scattered within Lecanoromycetidae and beyond, with several species nested in Lecanoraceae and Pilocarpaceae and others placed outside currently recognized families in Lecanorales and orders in Lecanoromycetidae. The phylogenetic affiliations of Schaereria and Strangospora are outside Lecanoromycetidae, probably with Ostropomycetidae. All species referred to as Lecidea sensu stricto based on morphology (including the type species, Lecidea fuscoatra [L.] Ach.) form, with Porpidia species, a monophyletic group with high posterior probability outside Lecanorales, Peltigerales and Teloschistales, in Lecanoromycetidae, supporting the recognition of order Lecideales Vain. in this subclass. The genus name Lecidea must be redefined to apply only to Lecidea sensu stricto and to include at least some members of the genus Porpidia. Based on morphological and chemical similarities, as well as the phylogenetic relationship of Lecidea pullata sister to Frutidella caesioatra, the new combination Frutidella pullata is proposed here.

We studied an Andean endemic group of species of the lichen-forming fungal genus Umbilicaria from the subalpine and low-alpine zone, with their biogeographic center in Bolivia and Peru. A number of species and varieties have been described from this element, but apparent instability in several morphological traits has made it difficult to precisely delimit taxa. Based on DNA sequences of nuclear ITS, LSU and mitochondrial SSU from extensive collections from Argentina, Bolivia, Chile, Colombia, Ecuador and Peru, we present here a molecular phylogenetic analysis of this Andean endemic element within genus Umbilicaria. All analyses (MP, ML and Bayesian) support a single origin for the element and a division into two major groups characterized by different apothecium types: the Umbilicaria dichroa group and U. calvescens group. Taxa U. krempelhuberi, U. peruviana and U. subcalvescens are nested withinn U. calvescens and are treated as conspecific with the latter species. The endemic element shares a most recent common ancestor with the Umbilicaria vellea group, which has a worldwide distribution and contains several asexually reproducing (sorediate) species. Independent reversals to sexual reproduction might explain the evolution of two types of apothecia in this monophyletic endemic lineage. A number of cosmopolitan, mostly high-alpine, species of Umbilicaria also present in the central Andes are related only remotely to the endemic element and do not exhibit speciation into endemics. Because the An-dean element dominates the Umbilicaria habitats of the low- and subalpine zones we propose that the founder colonized the Andes at a time when the mountains had not yet reached their current elevation while the high-alpine species arrived more recently.

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.

Pezizomycotina is the largest subphylum of Ascomycota and includes the vast majority of filamentous, ascoma-producing species. Here we report the results from weighted parsimony, maximum likelihood and Bayesian phylogenetic analyses of five nuclear loci (SSU rDNA, LSU rDNA, RPB1, RPB2 and EF-lalpha) from 191 taxa. Nine of the 10 Pezizomycotina classes currently recognized were represented in the sampling. These data strongly supported the monophyly of Pezizomycotina, Arthoniomycetes, Eurotiomycetes, Orbiliomycetes and Sordariomycetes. Pezizomycetes and Dothideomycetes also were resolved as monophyletic but not strongly supported by the data. Lecanoromycetes was resolved as paraphyletic in parsimony analyses but monophyletic in maximum likelihood and Bayesian analyses. Leotiomycetes was polyphyletic due to exclusion of Geoglossaceae. The two most basal classes of Pezizomycotina were Orbiliomycetes and Pezizomycetes, both of which comprise species that produce apothecial ascomata. The seven remaining classes formed a monophyletic group that corresponds to Leotiomyceta. Within Leotiomyceta, the supraclass clades of Leotiomycetes s.s. plus Sordariomycetes and Arthoniomycetes plus Dothideomycetes were resolved with moderate support.

The Lecanoromycetes includes most of the lichen-forming fungal species (> 13500) and is therefore one of the most diverse class of all Fungi in terms of phenotypic complexity. We report phylogenetic relationships within the Lecanoromycetes resulting from Bayesian and maximum likelihood analyses with complementary posterior probabilities and bootstrap support values based on three combined multilocus datasets using a supermatrix approach. Nine of 10 orders and 43 of 64 families currently recognized in Eriksson's classification of the Lecanoromycetes (Outline of Ascomycota--2006 Myconet 12:1-82) were represented in this sampling. Our analyses strongly support the Acarosporomycetidae and Ostropomycetidae as monophyletic, whereas the delimitation of the largest subclass, the Lecanoromycetidae, remains uncertain. Independent of future delimitation of the Lecanoromycetidae, the Rhizocarpaceae and Umbilicariaceae should be elevated to the ordinal level. This study shows that recent classifications include several nonmonophyletic taxa at different ranks that need to be recircumscribed. Our phylogenies confirm that ascus morphology cannot be applied consistently to shape the classification of lichen-forming fungi. The increasing amount of missing data associated with the progressive addition of taxa resulted in some cases in the expected loss of support, but we also observed an improvement in statistical support for many internodes. We conclude that a phylogenetic synthesis for a chosen taxonomic group should include a comprehensive assessment of phylogenetic confidence based on multiple estimates using different methods and on a progressive taxon sampling with an increasing number of taxa, even if it involves an increasing amount of missing data.

The Peltigera canina species complex consists of foliose lichenized bitunicate ascohymenial discomycetes forming section Peltigera within the genus Peltigera (Lecanoromycetes, lichen-forming Ascomycetes). To test the circumscription of highly polymorphic species and to resolve relationships among putative members of the P. canina complex, part of the nuclear ribosomal DNA large subunit (LSU rDNA) and the entire internal-transcribed spacer (ITS rDNA) were sequenced for 84 individuals representing 33 putative Peltigera taxa. Seventeen of the 25 taxa from the P. canina complex are well established and widely accepted. The remaining eight taxa have been proposed recently but are undescribed. A hypervariable region in ITS1 (ITS1-HR, sites 111-237 in our alignment) showed remarkable variation in length, especially in the P. canina complex, ranging from 8 to 126 bp, and contained several microsatellites. We describe here an alignment-free method to code such large gap-rich hypervariable regions for phylogenetic analyses. Variation among ITS1-HR sequences greatly contributed to species delimitation and species identification and can be a major asset to future population studies for specific species within section Peltigera. Sequences of ITS1-HR alone were sufficient to identify all existing species of Peltigera from the P. canina species complex and related sections Retifoveatae and Horizontales included in this study. However, only when INAASE (for short ambiguously aligned regions) and ITS1-HR coded characters were added to the combined analysis of nonambiguous LSU and ITS sites was it possible to reach the level of phylogenetic resolution and support necessary to disentangle the P. canina complex. We report here complete concordance between phylogenetically based and morphologically based species delimitation for 15 of the 17 species from the P. canina complex (P. canina, P. cinnamomea, P. degenii, P. evansiana, P. frigida, P. kristinssonii, P. laciniata, P. lambinonii, P. lepidophora, P. membranacea, P. monticola, P. ponojensis, P. praetextata, P. rufescens and P. ulcerata). Four of the eight newly proposed but undescribed taxa most likely represent new species (P. "fuscopraetextata", P. "neocanina", P. "neorufescens" and P. "scotteri") within the P. canina complex. We found that morphologically and chemically distinct P. didactyla s. str. and P. didactyla var. extenuata form two non-sister monophyletic entities, therefore the latter taxon should be recognized at the species level (P. extenuata). The North American and European populations of the morphologically uniform P. degenii might represent two sibling species because they were found to be genetically distinct and monophyletic. Two major monophyletic groups within the P. canina complex (CICADE = CInnamomea + CAnina + DEgenii group and PORUDI = POnojensis + RUfescens + DIdactyla group) seem to be correlated with different humidity preferences. Although some authors previously have suggested interspecies recombination within the P. canina complex, we did not find statistically significant evidence for this phenomenon based on LSU and ITS sequences.