Mats Wedin

Swedish Museum of Natural History · Department of Botany

Lichens are obligate symbioses between fungi and green algae or cyanobacteria. Most lichens resynthesize their symbiotic thalli from propagules, but some develop within the structures of already existing lichen symbioses. Diploschistes muscorum starts as a parasite infecting the lichen Cladonia symphycarpa, and gradually develops an independent Dip...

Although the high degree of non-monophyly and parallel evolution has long been acknowledged within the mazaediate Caliciaceae (Lecanoromycetes, Ascomycota), a natural re-classification of the group has not yet been accomplished. Here we constructed a multigene phylogeny of the Caliciaceae-Physciaceae clade in order to resolve the detailed relations...

Experiments to resynthesize lichens so far focused on co-cultures of fungal and algal partners. However, recent studies have revealed that bacterial communities colonize lichens in a stable and host-specific manner. We were therefore interested in testing how lichenized fungi and algae interact with selected bacteria in an experimental setup. We se...

The lichenicolous ‘heterobasidiomycetes’ belong in the Tremellomycetes (Agaricomycotina) and in the Pucciniomycotina. In this paper, we provide an introduction and review of these lichenicolous taxa, focusing on recent studies and novelties of their classification, phylogeny and evolution. Lichen-inhabiting fungi in the Pucciniomycotina are represe...

Dimorphism is a widespread feature of tremellalean fungi in general, but a little‐studied aspect of the biology of lichen‐associated Tremella. We show that T. macrobasidiata and T. variae have an abundant and widespread yeast stage in their life cycles that occurs in Lecanora lichens. Their sexual filamentous stage is restricted to a specific liche...

The nomenclature and taxonomy of Acarospora molybdina is revised using morphological and molecular data. The new combination Myriospora molybdina is proposed and Acarospora hysgina is recognized as a distinct species while A. brunneola is reduced to synonymy with A. hysgina . In its new circumscription M. molybdina is an arctic species, in Scandina...

The Lichinomycetes is an independent lichenized lineage within the Ascomycota comprising ca. 390 species and 50 genera. Very few studies have dealt with family and genus classification using molecular data and many groups are in need of thorough revision. Thus, we constructed a multilocus phylogeny (mtSSU, RPB2 and mcm7 gene regions) including 190...

The new combination Thalloidima squamatum is proposed for a morphologically and phylogenetically distinct species, until now included within the variation of T. sedifolium. Compared to T. sedifolium, the species is characterized by its larger squamules and apothecia, shorter ascospores, the pale color of the excipulum, and its habitat growing on mo...

Tremella caloplacae (Zahlbr.) Diederich is a species complex including at least nine different species. Here, we formally describe the new species Tremella elegantis , T. nimisiana , T. parietinae , T. pusillae and T. sorediatae . Tremella elegantis induces galls in the hymenium of Rusavskia elegans and forms 2-celled basidia, where cells rarely el...

Revisions of British and Irish Lichens

Lichenicolous fungi are a heterogeneous group of organisms that grow exclusively on lichens, forming obligate associations with them. It has often been assumed that cospeciation has occurred between lichens and lichenicolous fungi, but this has been seldom analysed from a macroevolutionary perspective. Many lichenicolous species are rare or are rar...

Volume 1 features members of the Basidiomycota and treats 197 species in Agaricales (4), Atheliales (2), Boletales (1), Cantharellales (11), Corticiales (12), Filobasidiales (8), Tremellales (129), Agaricostilbales (18), Cyphobasidiales (9), Microbotryomycetes (1) and incertae sedis (2), including three new genera (Kriegeriopsis, Parmeliicida, Zyzy...

Lichens are well-known examples of complex symbiotic associations between organisms from different Kingdoms. Microfungi in particular, establish diverse associations with the hosting lichen thallus, as species-specific parasites or transient co-inhabitants. The whole community of lichen-associated fungi constitute the ‘lichen mycobiome’ and compris...

Lichen symbioses are thought to be stabilized by the transfer of fixed carbon from a photosynthesizing symbiont to a fungus. In other fungal symbioses, carbohydrate subsidies correlate with reductions in plant cell wall-degrading enzymes, but whether this is true of lichen fungal symbionts (LFSs) is unknown. Here, we predict genes encoding carbohyd...

While most lichenicolous fungi belong to the Ascomycota, c. 5% of them are members of the Basidiomycota. Among these, the poorly known genus Crittendenia in the Pucciniomycotina has recently been described for lichenicolous fungi with minuscule needle-like synnematous basidiomata. Although only two species were hitherto known, the wide observed hos...

The Rostania occultata species complex ('Collema occultatum s. lat.') is revised in Fennoscandia and found to consist of four species, all epiphytes on deciduous trees: Rostania effusa A. Košuth., M. Westb. & Wedin sp. nov., R. occultata (Bagl.) Otálora et al., R. pallida A. Košuth., M. Westb. & Wedin sp. nov. and R. populina (Th. Fr.) A. Košuth.,...

Fungi are eukaryotes that play essential roles in ecosystems. Among fungi, Basidiomycota is one of the major phyla with more than 40,000 described species. We review species diversity of Basidiomycota from five groups with different lifestyles or habitats: saprobic in grass/forest litter, wood-decaying, yeast-like, ectomycorrhizal, and plant parasi...

The new genus Australidea Kantvilas, Wedin & M. Svensson is described to accommodate Lecidea canorufescens Kremp., a widespread lichen in temperate Australasia. It is characterized by a crustose thallus with a green photobiont, reddish brown, biatorine apothecia with an internally hyaline, cupulate proper exciple constructed of branched and anastom...

Lichen symbioses are generally thought to be stabilized by the transfer of fixed carbon compounds from a photosynthesizing unicellular symbiont to a fungus. In other fungal symbioses, carbohydrate subsidies correlate with genomic reductions in the number of genes for plant cell wall-degrading enzymes (PCWDEs), but whether this is the case with lich...

Rapid radiations in Fungi are only beginning to be studied with phylogenomic data. The evolutionary history of the lichenized fungal order Peltigerales has not been well resolved, particularly for the Collematineae. Here, we used concatenation and coalescent-based species tree methods to reconstruct the phylogeny of the Peltigerales based on sequen...

Assessing the ecological impacts of environmental change on biological communities requires knowledge of the factors driving the spatial patterns of the three diversity facets along extensive environmental gradients. We quantified the taxonomic (TD), functional (FD), and phylogenetic diversity (PD) of lichen epiphytic communities in 23 beech forest...

Parmeliaceae is the largest family of lichen-forming fungi with a worldwide distribution. We used a target enrichment data set and a qualitative selection method for 250 out of 350 genes to infer the phylogeny of the major clades in this family including 81 taxa, with both subfamilies and all seven major clades previously recognized in the subfamil...

Background: In this study, we investigate species limits in the cyanobacterial lichen genus Rostania (Collemataceae, Peltigerales, Lecanoromycetes). Four molecular markers (mtSSU rDNA, β-tubulin, MCM7, RPB2) were sequenced and analysed with two coalescent-based species delimitation methods: the Generalized Mixed Yule Coalescent model (GMYC) and a...

The identity of Calicium corynellum (Ach.) Ach. - Volume 52 Issue 4 - Maria Prieto, Ibai Olariaga, Sergio Pérez-Ortega, Mats Wedin

Characterizing functional trait variation and covariation, and its drivers, is critical to understand the response of species to changing environmental conditions. Evolutionary and environmental factors determine how traits vary among and within species at multiple scales. However, disentangling their relative contribution is challenging and a comp...

The lichenicolous fungus Rhagadodidymellopsis endocarpi (Dothideomyceta) growing on the thallus of the terricolous lichen Endocarpon pusillum is described from Spain and Australia as new to science. The new genus and species is compared with other taxa from the genera Didymellopsis and Zwackhiomyces (Xanthopyreniaceae, Collemopsidiales, Dothideomyc...

Here, we test the current generic delimitation of Rostania (Collemataceae, Peltigerales, Ascomycota) utilizing molecular phylogeny and morphological investigations. Using DNA sequence data from the mitochondrial SSU rDNA and two nuclear protein-coding genes (MCM7 and β-tubulin) and utilizing parsimony, maximum likelihood and Bayesian phylogenetic m...

Borderline lichens are simple mutualistic symbioses between fungi and algae, where the fungi form loose mycelia interweaving algal cells, instead of forming a lichen thallus. Schizoxylon albescens shows two nutritional modes: it can either live as a borderline lichen on Populus tremula bark or as a saprotroph on Populus wood. This enables us to inv...

Here, we show that Lichinodium (Lichinaceae, Lichinomycetes, Ascomycota) constitutes a formerly unrecognized lineage within the Leotiomycetes, thus being the first lichenized lineage recognized in the superclass Sordariomyceta (Leotiomycetes, Laboulbeniomycetes and Sordariomycetes). To infer the position of Lichinodium, we constructed two multilocu...

Zamora J.C., Millanes A.M., Etayo J. & Wedin M. 2018: Tremella mayrhoferi, a new lichenicolous species on Lecanora allophana. – Herzogia 31: 666–676.Tremella mayrhoferi, inducing galls on the hymenium of Lecanora allophana, is described. The description is based on molecular, morphological and ecological data of 27 specimens from Finland, Norway, S...

Phylogenomic datasets continue to enhance our understanding of evolutionary relationships in many lineages of organisms. However, genome-scale data have not been widely implemented in reconstructing relationships in lichenized fungi. Here we generate a data set comprised of 2556 single-copy protein-coding genes to reconstruct previously unresolved...

Recent finds of Leightoniella zeylanensis, classified variously in the Collemataceae and Pannariaceae, enabled us to generate DNA sequence data for investigating its phylogenetic affiliation. Newly generated sequence data from the internal transcribed spacer (ITS) region and the large subunit of the nuclear ribosomal DNA (nrLSU), the small subunit...

Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to am...

This is the first part of an ongoing taxonomic treatment of Bunodophoron ( Sphaerophoraceae , Lecanorales ) in the Neotropics, based on the molecular phylogenetic analysis of three markers together with studies of morphology and chemistry, and using the general mixed Yule coalescence (GMYC) method to delimit species boundaries. In the Neotropics, s...

Multiple drivers shape the spatial distribution of species, including dispersal capacity, niche incumbency, climate variability, orographic barriers, and plate tectonics. However, biogeographic patterns of fungi commonly do not fit conventional expectations based on studies of animals and plants. Fungi, in general, are known to occur across exceedi...

Niche ecospace as described by PC1 and PC2, derived from a phylogenetic PCA on the mean candidate species values for 19 bioclim variables. Candidate species are plotted by name, and eigenvectors as arrows. Together, PC1 (66.4%) and PC2 (20.2%) account for account for >86% of the variation. Temperature and precipitation variables are associated with...

Bioclimatic data for 19 Bioclim variables for candidate species. Latitude and longitude were used to extract bioclimatic variables at a spatial resolution of 2.5 min, using the R (R Core Team, 2015) package raster (Hijmans et al., 2015).

List of specimens included in this study.

Myriospora signyensis Purvis, Fdez-Brime, M. Westb. & Wedin is described from Signy Island, South Orkney Islands, Antarctica, where it occurs predominantly on quartz mica schist. This represents the first record of the genus for Antarctica. The distinctive interrupted photobiont arrangement places it within the genus Myriospora (formerly known as t...

Cryptodicus muriformis and Schizoxylon gilenstamii (Stictidaceae, Ostropales, Lecanoromycetes, Ascomycota) are described as new to science from collections made in Europe (Sweden, Austria, Switzerland) and North America (Arizona), based on phylogenetic analyses of three loci. Both species show unique morphological characters that distinguish them f...

Knowledge of the relationships and thus the classification of fungi, has developed rapidly with increasingly widespread use of molecular techniques, over the past 10–15 years, and continues to accelerate. Several genera have been found to be polyphyletic, and their generic concepts have subsequently been emended. New names have thus been introduced...

Tremella anaptychiae, a lichenicolous fungus growing on Anaptychia ciliaris, is described as new. Both morphological and molecular data (DNA sequences from the ITS and 28S regions) are used to characterize and distinguish it from other Tremella s. l. species. Tremella anaptychiae is closely related to T. parmeliarum but comparatively distantly rela...

Unraveling the complex relationship between lichen fungal and algal partners has been crucial in understanding lichen dispersal capacity, evolutionary processes, and responses in the face of environmental change. However, lichen symbiosis remains enigmatic, including the ability of a single fungal partner to associate with various algal partners. P...

Accurate species delimitations are of great importance for effectively characterizing biological diversity. Our criteria for delimiting species have changed dramatically over the last decades with the increasing availability of molecular data and improvement of analytical methods to evaluate these data. Whereas reciprocal monophyly is often seen as...

Species have traditionally been identified and described using morphological characters. Recently, analyses of sequence data have revealed that traditional species delimitation frequently underestimates the diversity of organisms. The main goal of this work was to study species boundaries in the genus Pectenia and elucidate the biogeographic histor...

Lichenized Fungi and the Evolution of Symbiotic Organization, Page 1 of 2 Abstract Lichen symbioses comprise a fascinating relationship between algae and fungi. The lichen symbiotic lifestyle evolved early in the evolution of ascomycetes and is also known from a few basidiomycetes. The ascomycete lineages have diversified in the lichenized stage...

Three new species of Biatoropsis are formally described based on our previous molecular studies, and on additional molecular, morphological, and ecological data. Biatoropsis protousneae sp. nov. is confined to Protousnea dusenii. Biatoropsis minuta sp. nov. is characterized by the small and brown to black basidiomatal galls, and by growing on Usnea...

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 speleoth...

List of fungal names, isolate information and GenBank and EMBL accessions of Bacillicladium, Bradymyces and related taxa of the Chaetothyriomycetidae. Accession numbers in bold were generated for this study. Taxa indicated with an asterisk (*) represent environmental samples. (DOCX)

The place of publication and typification of the generic name Naematelia is discussed, and N. encephala is confirmed as the correct name of the type of the genus name. That name was a replacement name for the earlier N. encephaliformis, which is lectotypified by a Willdenow plate; as selection of an epitype cannot be justified at present, a sequenc...

The new combination Phaeotremella foliacea (Pers.) Wedin, J.C. Zamora & Millanes is coined and taken up as the current name for one of the most common species of the recently resurrected genus Phaeotremella Rea. Key words – Tremella – nomenclature Introduction Recently, Liu et al. (2016) presented a major reclassification of the Tremellomycetes (Ag...

Four new lichenicolous Tremella species are described and characterized morphologically and molecularly. Tremella celata grows on Ramalina fraxinea, inducing the formation of inconspicuous galls, and having hyphae with incomplete clamps. Tremella endosporogena develops intrahymenially in the apothecia of Lecanora carpinea, having single-celled basi...

We investigated the phylogenetic relationships in the cyanolichen family Placynthiaceae to test the current generic delimitations, where the monotypic Collolechia is currently accepted as distinct, based on differences in ascospores, ascus apex characteristics and the leprose thallus. Bayesian and maximum likelihood phylogenetic analyses of two seq...

Pucciniomycotina is a highly diverse group of fungi, showing a remarkably wide range of life-styles and ecologies. However, licheninhabiting fungi are only represented by a few species included in the genera Chionosphaera and Cystobasidium, and their phylogenetic position has never been investigated. Phylogenetic analyses using the nuclear SSU, ITS...

Families and genera assigned to Tremellomycetes have been mainly circumscribed by morphology and for the yeasts also by biochemical and physiological characteristics. This phenotype-based classification is largely in conflict with molecular phylogenetic analyses. Here a phylogenetic classification framework for the Tremellomycetes is proposed based...

Fourteen species of lichenized or lichenicolous fungi are reported new to either Norway or Sweden or both countries. Several of these are rare and almost unknown. The reported species are: Acarospora insignis (new to Norway), A. pyrenopsoides (Norway, Sweden), A. versicolor (Norway), Calvitimela perlata (Sweden), Lecidea degeliana (Sweden), Nephrom...

We studied the evolutionary history of the Parmeliaceae (Lecanoromycetes, Ascomycota), one of the largest families of lichen-forming fungi with complex and variable morphologies, also including several lichenicolous fungi. We assembled a six-locus data set including nuclear, mitochondrial and low-copy protein-coding genes from 293 operational taxon...

This paper is a compilation of notes on 142 fungal taxa, including five new families, 20 new genera, and 100 new species, representing a wide taxonomic and geographic range. The new families, Ascocylindricaceae, Caryosporaceae and Wicklowiaceae (Ascomycota) are introduced based on their distinct lineages and unique morphology. The new Dothideomycet...

Tremella cetrariicola is shown to be heterogeneous and to represent two phylogenetic sister species, which are shown here to be distinct in the morphology of the galls, basidia and basidiospores, and in their host selection. Tremella cetrariicola s. str. is confined to Tuckermannopsis, whilst the material on Cetrariella delisei is described here as...

The cyanolichen genus Epiphloea is currently included within the Heppiaceae (Lichinomycetes) based on ascus characteristics. The presumed presence of a prototunicate ascus has been used as support for this classification, despite the incongruence with other characters (e.g. spores). Here, we use a molecular phylogeny of the two markers mtSSU rDNA a...

This paper is a compilation of notes on 142 fungal taxa, including five new families, 20 new genera, and 100 new species, representing a wide taxonomic and geographic range. The new families, Ascocylindricaceae, Caryosporaceae and Wicklowiaceae (Ascomycota) are introduced based on their distinct lineages and unique morphology. The new Dothideomycet...