Sixteen sorediate epiphytic species of Lecanora with atranorin from Europe are reported here. Lecanora substerilis is described as a new species from Carpathian beech forests in the Czech Republic, Slovakia, Romania and Ukraine; it belongs to the L. subfusca group in its strict sense and is characterized by its usually verrucose thallus, sorediate apothecial margin, epihymenium with coarse granules at paraphyses tips, amphithecium with large crystals and it produces atranorin and fatty acid(s). A new, yellow chemotype of L. barkmaniana containing pulvinic acid derivatives is recognized from Austria. Morphological, ecological and chemical variation in L. exspersa, L. farinaria and L. variolascens is discussed in detail, and brief comments on the remaining 11 species are provided. Evaluation of the type material and molecular data indicate that the predominantly saxicolous L. caesiosora is a sorediate form of L. cenisia. Molecular data confirmed the identities of the sorediate forms of L. albella and L. allophana that are conspecific with their fertile counterparts. New Central European localities are listed for the rare species, L. barkmaniana, L. exspersa, L. mughosphagneti, L. norvegica and L. variolascens. Positions in ITS and mtSSU phylogenies are outlined for most species. Identification keys to fertile as well as sterile populations are provided.

Rhizocarpon smaragdulum Davydov & Yakovchenko sp. nov. is described and a phylogenetic analysis (ITS, mtSSU) is presented, confirming its distinctiveness and indicating a sister relationship with R. suomiense and R. subgeminatum. The species is unique among yellow Rhizocarpon species in having a single hyaline ascospore per ascus. The phylogenetic tree suggests that the number of ascospores per ascus has been reduced in Rhizocarpon more than once during the course of its evolution. Two new distributional records are also reported: Rhizocarpon atroflavescens is new for Siberia and R. norvegicum is new for the Altai Mountains. Rhizocarpon norvegicum in this region grows on rocks and is also lichenicolous on Acarospora bullata.

Molecular studies have shown the type collection of Omphalina oreades to be conspecific with a small brown basidiolichen from the Appalachian range in Newfoundland, both with 4-spored basidia. Two sequences deposited in GenBank, originally identified as O. grisella, fell in the same clade. Sequences of the type collection of Omphalia grisella, with 2-spored basidia, formed a sister clade together with two GenBank deposits, one identified as O. grisella and the other as Omphalina velutina. Omphalina oreades is recombined here as Lichenomphalia oreades comb. nov., and the species redescribed and illustrated. Sequences of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS rDNA) from the algae associated with two collections of L. oreades fell within a highly supported clade with members of an undetermined species of Coccomyxa. The most abundant algal ribosomal large subunit sequence from granules at the base of a different collection matched GenBank sequences identified as Chloroidium ellipsoideum, which is probably either a free-living algal species or a partner to a species of Trapeliopsis. The second most abundant sequence matched Coccomyxa subellipsoidea and is the most likely photobiont of L. oreades. Further studies are required to elucidate the relationship of L. velutina to these taxa.

Biological soil crusts are communities composed of cryptogamic organisms such as lichens, mosses, cyanobacteria and green algae that form a skin on soils in areas where vascular plants are excluded or limited by water availability or temperature. The lichen Psora decipiens (Hedw.) Hoffm. is a characteristic key organism in these communities in many different biomes. The species has a generalistic ecology and high morphological variation, which contributes to the ability of the species to withstand environmental changes. We investigated whether different populations, based on site and associated morpho-anatomical differences, incorporate functional water relations and how/whether this was driven by changes in abiotic factors. Samples were collected from two climatically distinct sites, one ‘dry’ site in southern Spain and one ‘wet’ site in the Austrian Alps. Our results showed that samples from the dry site had a significantly thicker epinecral layer, higher specific thallus area, a faster water uptake and contained more water per dry mass, all of which contributed to a much slower drying rate. Both populations showed a highly adjusted water gain that incorporates functional water relations and diffusion properties as a result of local water availability. We show eco-physiological and morphological mechanisms that underlie the high variability in P. decipiens and suggest how these might provide ecological benefits for this generalist lichen species.

This study aims to quantify the size-dependency of important hydration traits in Lobaria amplissima, L. pulmonaria and L. virens sampled in sympatric populations on deciduous tree trunks in southern Norway, and to discuss possible implications of species-specific traits for the ecological niches of these old forest cephalolichens. Traits measured were thallus size (area and mass), specific thallus mass (STM), internal (WHCinternal) and external water-holding capacity (WHCexternal), and water content (WC) after shaking and after blotting. Lobaria amplissima had the highest WHCinternal, 2·6 times higher than L. pulmonaria with the lowest WHCinternal. WHCinternal, driven by STM, strongly depended on size. WHCexternal was 28% (L. virens) to 47% (L. pulmonaria) of the WHCinternal. Unlike WHCinternal, WHCexternal did not depend on thallus area, meaning that WHCexternal is proportionally higher for smaller compared with larger thalli. The most widespread species, L. pulmonaria, benefits from a flexible hydration strategy due to low STM, facilitating the use of more diverse water sources than the other two species that depend more on rain, particularly L. amplissima with the highest STM and thus relatively high WHCinternal. For L. virens, a combination of less specialized hydration traits and a low tolerance to higher light intensity probably jeopardizes its survival outside rainforest habitats.

Thin-layer chromatography (TLC) still enjoys widespread popularity among lichenologists as one of the fastest and simplest analytical strategies, today remaining the primary method of assessing the secondary product content of lichens. The pitfalls associated with this approach are well known as TLC leads to characterizing compounds by comparison with standards rather than properly identifying them, which might lead to erroneous assignments, accounting for the long-held interest in hyphenating TLC with dedicated identification tools. As such, commercially available TLC/Mass Spectrometry (MS) interfaces can be easily connected to any brand of mass spectrometer without adjustments. The spots of interest are extracted from the TLC plate to retrieve mass spectrometric signals within one minute, thereby ensuring accurate identification of the chromatographed substances. The results of this hyphenated strategy for lichens are presented here by 1) describing the TLC migration and direct MS analysis of single lichen metabolites of various structural classes, 2) highlighting it through the chemical profiling of crude acetone extracts of a set of lichens of known chemical composition, and finally 3) applying it to a lichen of unknown profile, Usnea trachycarpa.