Caloplaca sol is described as a new species from limestone and basic siliceous rocks on the southern and western coasts of Great Britain. It is characterized by a well-developed, crustose, non-placodioid, epilithic, cracked, orange-yellow thallus, almost concolorous apothecia up to 0·66 mm diameter, and ascospores c. 11·0–12·2–13·0 µm long with a septum c. 0·4×the ascospore length. Caloplaca dalmatica is related but differs in the endolithic or only thinly epilithic thallus. Caloplaca marina is darker orange in colour, with more convex areoles, and is mostly confined to the splash zone of the seashore. Caloplaca maritima differs in the typically more convex, sometimes isolated areoles, and often in the presence of a crenulate thalline margin in young apothecia. Caloplaca itiana is newly reported from Great Britain from coastal limestone; it differs from C. sol in the thallus being endolithic or almost so, and from C. dalmatica in the more completely endolithic thallus and the larger ascospores.

Usnea viktoriana P. Clerc & Otte is described as new. It is characterized by the presence of alectorialic acid as major secondary compound mainly present in the aggregated efflorescent soralia with long isidiofibrils. Usnea parafloridana K. Mark, Will-Wolf & Randlane is synonymized with U. praetervisa (Asahina) P. Clerc. Both U. viktoriana and U. praetervisa are supported by molecular analysis. A key to the shrubby-subpendulous sorediate Usnea species in Europe is provided.

Enterographa sorediata is a corticolous, crustose lichen endemic to the southern part of Great Britain where it is confined to old-growth woodlands. This lichen is rarely fertile and mainly characterized by a sorediate thallus producing protocetraric acid. However, phylogenetic analyses using nuLSU, RPB2 and nuITS sequences suggest that E. sorediata belongs to the genus Syncesia and is conspecific with S. myrticola. This is corroborated by the chemistry and the recent observation of a thallus with both fully developed S. myrticola-like apothecia and soralia. This provides further evidence of the difficulties involved in correctly placing sorediate sterile morphs of crustose lichens into particular genera without using molecular data. An updated distribution map of S. myrticola for Great Britain and Ireland is provided, showing that the sorediate morph extends more inland whereas the fertile morph is more coastal.

Two new species of Arthoniaceae are described from old-growth European forests: Arthonia thoriana from Horner Combe in Great Britain and Inoderma sorediatum from the Białowieża Forest in Poland. Phylogenetic analyses using mtSSU sequences were used to determine the generic affiliation of the two species. Arthonia thoriana is characterized by a non-lichenized white thallus, pallid brown, white pruinose ascomata of 0·12–0·30 mm diam., richly anastomosing paraphysoids and (1–2–)3-septate ascospores of 9–12×3·0–3·5 µm. Inoderma sorediatum differs from all other species of the genus by a sorediate thallus and the production of confluentic acid. It is the sister species to I. afromontanum in our phylogenetic analyses. The discovery of the new species supports the high value of these forests for biodiversity action plans. Phylogenetic analyses also place Schismatomma niveum in the Arthoniaceae and the new genus Snippocia is described to accommodate it. The genus Leprantha is resurrected for its type species (L. cinereopruinosa). A lectotype is designated for Arthonia pruinosella.

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, species in this genus grow on the ground or on shrubs in the páramos, and as epiphytes in the montane rainforests. We describe here a new species from the páramos of Colombia, Bunodophoron crespoae Soto, M. Prieto & Wedin sp. nov., and discuss its distinction from another large and common páramo species Bunodophoron flabellatum (Hue) Soto, M. Prieto & Wedin comb. nov. Both species are primarily terrestrial in the páramos, although B. flabellatum may occasionally also grow as an epiphyte. Bunodophoron crespoae is characterized by the white, c. 10–13 cm long, subterete to narrowly flattened, main branches. It differs from the otherwise similar B. flabellatum by being distinctly subterete, more abundantly branched, and by having smaller ascospores. Both are distinguished from the primarily epiphytic B. melanocarpum by the considerably larger thallus size, with the main branches of B. melanocarpum rarely exceeding 3·5 cm in length and 2 mm in width.

The molecular phylogeny of Bacidia s.s. in the Russian Far East was investigated using 62 nucleotide sequences from the ITS nrDNA region, 22 of which were newly obtained. Phylogenetic reconstructions employed Bayesian inference and maximum likelihood searches using MrBayes and RAxML. In addition, ITS2 secondary structures added further support using Compensatory Base Changes. As a result of morphological and phylogenetic studies, four new species of Bacidia are described. Bacidia areolata sp. nov. belongs to the suffusa group. It was collected once in Khabarovskiy Krai, the Russian Far East, on the bark of Acer tegmentosum and is closely related to B. suffusa but differs in having a smooth, cracked to areolate thallus and shorter spores. Bacidia elongata sp. nov. is a member of the fraxinea group and is similar to B. fraxinea but differs in having a wide zone of cells with enlarged lumina along the edge of the exciple. In fact, this zone of enlarged cells, in combination with its overall habit, places it morphologically close to B. suffusa, B. millegrana and B. campalea. Bacidia kurilensis sp. nov. is a basal member of the laurocerasi group and closely related to B. biatorina, B. heterochroa, B. laurocerasi and B. salazarensis. However, the combination of a granular thallus, large black apothecia and a green hue in the upper part of the exciple edge as well as in the epihymenium sets it apart from the species mentioned above. Bacidia sachalinensis sp. nov. resolves as a strongly supported member of the polychroa group and is known from a single locality in Sakhalin, the Russian Far East. Its thallus structure and apothecium colour are variable, which is typical for the polychroa group, but it differs from B. polychroa by having shorter spores with fewer septa and a mainly smooth to areolate thallus.

The two corticolous species Fuscidea lightfootii (Sm.) Coppins & P. James and F. pusilla Tønsberg are morphologically and chemically similar and it has been suggested that they are conspecific. We investigated the interspecific relationship between F. lightfootii and F. pusilla using ITS, LSU and mtSSU rDNA. The combined multigene phylogeny shows that these species are genetically distinct. They are similar in ascocarp anatomy but in thallus morphology and substratum preferences there may be slight differences between them. Moreover, F. pusilla displays a broader ecological range than F. lightfootii. Even though some morphotypes appeared distinct and may be assigned to one of the two species with some degree of certainty, the use of DNA sequencing is recommended for their identification. Epitypes are designated for both species.

Trapelia is a small genus of worldwide distribution. Trapelia coarctata has long been regarded as a morphologically variable species and phylogenetic studies have suggested that it is non-monophyletic, or at least that species are frequently misidentified. The phylogenetic relationships of freshly-collected material of Trapelia were studied using ITS, mitochondrial SSU rDNA and to a small extent also beta-tubulin sequence data, together with chemical and morphological characters. Sequence data combined with morphology and chemistry confirm that the diversity of the genus at species-level has been underestimated. Trapelia coarctata is defined in a more restricted way and many specimens previously referable to this taxon are assigned to the reinstated species T. elacista, which differs in subtle morphological characters including a crack separating the thallus and apothecium in well-developed thalli. Trapelia involuta is reinstated as a separate, though closely related, species to T. glebulosa based on sequence data, morphology and chemistry, and is lectotypified. Trapelia collaris is a distinctive species described as new from Great Britain which has an extensive, cracked thallus with abruptly thickening marginal areoles arising on an inconspicuous prothallus, relatively small apothecia (rarely exceeding 300 µm diameter) and contains 5-O-methylhiascic acid as the major secondary substance. Trapelia obtegens is shown to include frequent non-sorediate morphs which have doubtless been misidentified as other species. The number of species of Trapelia considered to occur in Europe is thus raised from five to eight. The genus is newly reported for the Falkland Islands where seven species occur: T. coarctata, T. placodioides, T. sitiens sp. nov. (with a thin, extensive thallus, sessile apothecia, 5-O-methylhiascic acid as the major secondary substance and the presence of conidiomata), T. tristis sp. nov. (with relatively small apothecia up to 460 µm diameter, presence of gyrophoric acid as the major substance and an absence of conidiomata) and three unidentified species represented by very sparse material. All the species studied, with the possible exception of the three unidentified species, can usually be distinguished by morphological features, particularly the method of development of the thallus and the shape and distribution of the areoles, but morphological variation in response to microhabitat variation is likely to make a proportion of specimens difficult to assign to species in the absence of sequence data.

Recently, nine species of lichenicolous fungi were found growing on Cetraria aculeata (Parmeliaceae) in a sand dune system in the Ukraine. One of them, Didymocyrtis trassii, is described here as new to science. This species is similar to D. pseudeverniae but differs in having smaller pycnidia, smaller obpyriform to clavate conidia as well as its DNA sequence. The new monotypic lichenicolous genus Katherinomyces is described here. Acremonium lichenicola s. l., Eonema pyriforme, Didymocyrtis cladoniicola and Lichenoconium erodens are reported for the first time on Cetraria aculeata. Furthermore, E. pyriforme is reported for the first time from lichen thalli. Acremonium lichenicola, E. pyriforme and Taeniolella rolfii are new for the mycobiota of the Ukraine. A key to the eleven known lichenicolous species on Cetraria aculeata is provided.

Sporastatia crassulata Yakovchenko & Davydov sp. nov. is described and a phylogenetic analysis (mtSSU) is presented, confirming its distinctness and indicating a sister relationship with S. testudinea. The species is unique among Sporastatia species in having a distinctly squamulose, thick, uneven thallus composed of convex, rounded squamules irregularly ascending in the central part of the thallus. The new combination Sporastatia karakorina (Poelt & Obermayer) Davydov & Yakovchenko is proposed. The type specimen of S. subasiatica was examined. A key to the six species of Sporastatia is given. Mountainous Central Asia appears to be the centre of species diversity and endemism for Sporastatia.

The new species Ramalina fleigiae from Brazil is described growing on rocks in riverbeds in high altitude grasslands of southern Brazil. It grows in areas with constant water flow, sometimes almost immersed, and always in exposed habitats. Through an integrative approach, the detailed description of R. fleigiae includes morphological, anatomical, ecological, chemical and molecular data. Ribosomal DNA-based phylogenies suggest that R. fleigiae is more closely related to a species that shares its habitat preference (R. laevigata) than to the morphologically and chemically similar R. exiguella and R. gracilis. Ramalina fleigiae and R. laevigata can be distinguished by thallus morphology (irregularly flat branches in R. fleigiae vs. flat to canaliculate in R. laevigata) and pattern of chondroid tissue, as genetic distances between them are compatible with the interspecific range. It is possible that many species of Ramalina still remain hidden within the morphological or chemical variation of currently accepted species. Combining ecological, anatomical and molecular data will improve our future understanding of this genus.

The lichen species Cladonia angustiloba is characterized by a well-developed primary thallus and narrow squamules which show deep incisions, and the presence of usnic and fumarprotocetraric acids. Morphologically it is similar to C. foliacea and C. convoluta, from which it can be distiguished by the squamule size and morphology. Since similar characters were used to distinguish C. foliacea from C. convoluta which do not represent different lineages, it is necessary to examine the taxonomic status of C. angustiloba by means of DNA sequences. In this study, the species delimitation within the C. foliacea complex was studied by sequencing three loci, ITS rDNA, cox1 and RPB2. The data were analyzed by means of phylogenetic and species delimitation methods (GMYC, PTP, ABGD and BPP). Our results show that none of the three species is monophyletic. Most of the species delimitation methods did not support the current species as evolutionary lineages. Only some of the BPP analyses supported C. angustiloba as a species distinct from C. foliacea and C. convoluta. However, the hypothesis that considers the C. foliacea complex as constituted by a unique species obtained the best Bayes Factor value. Therefore, C. angustiloba and C. convoluta are synonymized with C. foliacea. A new, thoroughly checked synonymy with typifications of the whole C. foliacea complex is presented. An updated survey of the world distribution data is compiled.

Bacidina mendax, described here as a new lichen species, appears to be common and widespread, at least in Central Europe. Analyses of the ITS rDNA region and the morphology of specimens showed an intraspecific variation in the new taxon. It differs from B. neosquamulosa in the lack of a subsquamulose thallus, and from B. caligans in its longer and only slightly curved to apically hooked conidia and lack of a granular (sorediate) thallus. Since ITS rDNA data support the inclusion of Bacidia pycnidiata Czarnota & Coppins in the genus Bacidina, a new combination is proposed.

An account of thelotremoid species of Graphidaceae in India is provided, which includes 124 species in 24 genera. Ocellularia and Thelotrema are the most diverse genera represented by 34 and 18 species, respectively. Type specimens were re-examined and additional samples studied morphologically and chemically. One new species, Ocellularia upretii S. Joshi, Divakar, Lumbsch & Lücking, is described; it is characterized by a greyish green thallus, porinoid ascomata, brown proper exciple, simple, carbonized columella, clear hymenium, transversely septate, amyloid ascospores of 110–125×15–20 µm and an absence of secondary metabolites. Asteristion australianum, Astrochapsa mirabilis, Cruentotrema cruentatum, C. kurandense, Ocellularia violacea and Thelotrema adjectum are reported as new to the country, and Astrochapsa mirabilis, Melanotrema submicrosporoides, Ocellularia annuloelevata, O. subkeralensis and Rhabdodiscus verrucoisidiatus are proposed as new combinations. Diploschistes awasthii, Ocellularia gupeti, O. leucina, O. mahabalei, Thelotrema confertum and T. verrucorugosum are synonymized under D. scruposus, O. neomasonhalei, O. urceolaris, O. thelotremoides, Chapsa leprocarpoides and T. rugatulum, respectively, with Ocellularia canariana and O. verrucomarginata reduced to synonymy with O. allosporoides.

During lichenological explorations of tropical montane forests in Kenya, a remarkable new lichenicolous fungus was repeatedly found growing on thalli of the epiphytic tripartite cyanolichen Crocodia cf. clathrata. Molecular phylogenetic analyses placed the fungus within Gomphillaceae (Ostropales, Lecanoromycetes), a family mainly of lichen-symbiotic species in the tropics. The anatomical features (unitunicate, non-amyloid asci and simple, septate paraphyses) as well as the hemiangiocarpic ascoma development confirm its taxonomic affinity. DNA sequence data showed the closest relationship was with Gyalidea fritzei, followed by Corticifraga peltigerae. A monotypic genus, Taitaia, is introduced to incorporate a single species, T. aurea. The new fungus is characterized by aggregated ascomata with yellow margins and salmon red discs developing from a single base.

Maintenance of biodiversity in managed forested landscapes requires detailed knowledge of the ecological requirements of specialist organisms linked to key microhabitats. Here we examine the relationship of 37 lichenized and unlichenized epiphytic calicioid species to stand age and substratum type in seven pairs of mid-seral (70–165 y) and old (220–470 y) forest stands in humid east-central British Columbia. Based on our inventory of eight host tree species, total calicioid diversity and mean species richness are highest in old stands, with 12 species not detected and nine additional species much less frequent in mid-seral stands. Thuja plicata supports by far the highest level of total calicioid diversity, with 31 of 37 species; mostly associated with very old trees. Owing primarily to the late recruitment of lignicolous calicioids, stand-level calicioid richness continues to increase into the 5th century after stand initiation. Our study thus has two major findings pertinent to the maintenance of forest biodiversity in managed forests: first, stand-level calicioid richness increases slightly for at least three centuries past the acquisition of old-growth status; second, remnant trees and snags carried forward into mid-seral, regenerating stands enhance overall calicioid species richness. These results suggest that very old old-growth (= ‘antique’) forests might play an important role in the long-term maintenance of calicioid species richness, further suggesting that the standard practice of lumping all forests above a set age into a single old-growth category is not ecologically tenable for all taxonomic groups.

The lichen species of the genus Thamnolia, with their striking wormlike thalli and frequent occurrence in arctic and tundra environments, have often been debated with regard to the use of chemistry in lichen taxonomy. Phylogenetic studies have arrived at different conclusions as to the recognition of species in the genus, but in a recent study based on the analyses of six nuclear markers (genes or noncoding regions) of a worldwide sample of Thamnolia, we showed the existence of three well-supported lineages with two different chemistries and geographical distributions. Here, we present two analyses based on ITS and three markers, respectively, which were extended from the study mentioned above to include type specimens and additional Thamnolia strains and taxa. In these analyses the same three clades were retrieved. A putative DEAD-box helicase is used here for the first time as an informative phylogenetic marker to provide taxonomic resolution at species level. The distribution of morphological and chemical characters across the phylogeny was analyzed and it was concluded that three morphologically cryptic, but genetically well supported, species occur: T. vermicularis s. str., T. subuliformis s. str. and T. tundrae sp. nov. Thamnolia vermicularis s. str. contains individuals with uniform secondary chemistry (producing thamnolic acid) and a rather limited distribution in the European Alps, Tatra Mts and the Western Carpathians, a distribution which might result from glacial survival in an adjacent refugium/refugia. Thamnolia subuliformis s. str. is widely distributed in all hemispheres and the samples contain two chemotypes (either with thamnolic or squamatic acids). Thamnolia tundrae is described as new; it produces baeomycesic and squamatic acids, and has a distribution limited to the arctic tundra of Eurasia extending to the Aleutian Islands in North America. It may have survived the latest glaciation in coastal refugia near its present distribution. Thus, secondary chemistry alone is not suitable for characterizing species in Thamnolia, secondary chemistry and geographical origin are informative, and the ITS region can be confidently used for species recognition. Nomenclatural notes are given on several other names that have been used in Thamnolia.