The genus Arthothelium A. Massal. in Tasmania comprises ten species. Five of these are described as new: A. bacidinum Kantvilas, a saxicolous, littoral species with subglobose apothecia, non-macrocephalic ascospores, 25−40 × 11−19 μm, and containing the pigment Endoaurantiacum-gold which yields a K+ red reaction; A. insolitum Kantvilas, lichenicolous in rainforest and characterized by subglobose apothecia, very large, non-macrocephalic ascospores, 50−80 × 22−40 μm, and containing the pigment Interveniens-brown which reacts K+ olive green; A. macounioides Kantvilas, corticolous in wet forest and characterized by sessile, convex apothecia, macrocephalic ascospores, 29−42 × 11−18 μm, and containing the pigment Endoaurantiacum-gold; A. magenteum Kantvilas, a common wet forest epiphyte with applanate apothecia, non-macrocephalic ascospores, 25−55 × 11−22 μm, and containing a unique maroon-red, K+ pink pigment; and A. subtectum Kantvilas, a saxicolous species with convex apothecia, macrocephalic ascospores, 22−36 × 9−14 μm, and containing Endoaurantiacum-gold. The New Zealand species A. endoaurantiacum Makhija & Patw. and A. suffusum (C. Knight) Müll. Arg., and the Australian A. velatium Müll. Arg. are recorded for Tasmania for the first time. The names A. obtusulum (Nyl.) Müll. Arg., A. pellucidum (C. Knight) Müll. Arg. and A. polycarpum Müll. Arg. are considered synonyms of the widespread A. ampliatum (C. Knight & Mitten) Müll. Arg. Arthothelium ferax Müll. Arg. is a synonym of A. interveniens (Nyl.) Zahlbr. and A. subspectabile Vĕzda & Kantvilas is a synonym of A. suffusum. The sole record of A. macrothecum (Fée) A. Massal. from Tasmania is found to be based on a misidentification. A key to the species is provided. The importance of apothecial pigments, apothecial morphology and ascospore septation is discussed, and three pigments are characterized by their appearance in water and other standard media.

The new genus Sinuicella, an early successional lichen, was found on bare soil in Oregon, USA. The thallus is minute fruticose, grey to nearly black, branching isotomic dichotomous, branches round, 20–90 μm wide in water mount. The cortex is composed of interlocking cells shaped like jigsaw puzzle pieces. Spores are hyaline, 1-septate, 25–40(–50) × 6.5–9(–11) μm. Maximum likelihood phylogenetic analyses on multilocus data sets, first spanning the entire order Peltigerales and then restricted to Peltigeraceae with extended sampling from Solorina and Peltigera, revealed the placement of Sinuicella outside of currently recognized genera, sister to Peltigera, with high support. Based on the phylogenetic, morphological and ecological distinctness of Sinuicella, we formally introduce a new genus represented by the single species S. denisonii. The cyanobiont of S. denisonii is Nostoc from phylogroup XL, Clade 2, Subclade 3 based on the rbcLX marker.

The lichen genus Lecanactis Körb. in Tasmania comprises six species: L. abietina (Ach.) Körb., which is widespread and pan-temperate; L. latispora Egea & Torrente and L. neozelandica Egea & Torrente, both shared with New Zealand and with the former recorded here from the Auckland Islands for the first time; L. mollis (Stirt.) Frisch & Ertz, shared with Victoria and New Zealand; L. aff. dilleniana (Ach.) Körb., a European species recorded provisionally for Tasmania on the basis of several sterile collections; L. scopulicola Kantvilas, which is described here as new to science and apparently a Tasmanian endemic. This new taxon occurs in rocky underhangs and is characterized by a thick, leprose thallus containing schizopeltic acid, and 3-septate ascospores, 19–30 × 4.5–6 μm. Short descriptions and a discussion of distribution and ecology are given for all species. A key for all 11 Australian species of the genus is provided, including L. subfarinosa (C. Knight) Hellb. and L. tibelliana Egea & Torrente, which are recorded for Australia for the first time, and L. platygraphoides (Müll.Arg.) Zahlbr., a first record for New South Wales. Lecanactis spermatospora Egea & Torrente and L. sulphurea Egea & Torrente are also included.

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.

Rinodina is a widespread, polyphyletic genus of crustose Physciaceae with c. 300 species worldwide. A major missing link in understanding its global biogeography has been eastern Asia where the genus has never been systematically revised. Here we review specimen and literature records for Rinodina for north-eastern Asia (Russian Far East, Japan and the Korean Peninsula) and recognize 43 species. We describe two species, R. hypobadia and R. orientalis, as new to science. Rinodina hypobadia is distinguished by its pigmented hypothecium, Dirinaria-type ascospores and pannarin in both thallus and epihymenium. Rinodina orientalis is characterized by its erumpent apothecia that remain broadly attached, with discs sometimes becoming convex and excluding the thalline margins, ascospores belonging to the Physcia-type and secondary metabolites absent. Nine other species are reported from the region for the first time. These include R. dolichospora, R. freyi, R. metaboliza, R. sicula, R. subminuta and R. willeyi. Of particular biogeographical interest are three additional new records that have western North American–eastern Asian distributions: the corticolous species R. endospora, R. macrospora and R. megistospora. Six species have the better known eastern North American–eastern Asian distributions: R. ascociscana (syn. R. akagiensis, R. melancholica), R. buckii, R. chrysidiata, R. subminuta, R. tenuis (syn. R. adirondackii) and R. willeyi, and two have eastern North American–eastern Asian–European distributions: R. excrescens and R. moziana (syn. R. destituta, R. vezdae). Our study begins to close one of the largest gaps in our knowledge of circumboreal species distributions in Rinodina and, together with previous studies in North America and Europe, provides new insights into circumboreal crustose lichen biogeography. Rinodina cinereovirens (syn. R. turfacea var. cinereovirens) is also reported as new to North America.

Most lichen-forming fungi are characterized by the production of secondary metabolites. Differences in metabolite patterns have frequently served to distinguish lichen taxa with subsequent controversies about the rank of chemical variants (chemotype, variety, subspecies or species). Using a model system, we investigate whether production of norstictic acid within a group of lichenized ascomycetes is correlated with phylogenetic patterns, population differentiation or single and multi-locus haplotypes. Our study is based on DNA sequences of three gene loci (ITS, GPD, mtLSU) together with HPLC (311) and TLC (594) data from a total of 594 samples of three closely related fruticose lichens: Cetraria aculeata and C. muricata without norstictic acid, and C. steppae with norstictic acid. In nature, C. aculeata and C. steppae often occur together and the status of C. steppae as a separate species has been questioned. Our results show geographical but no phylogenetic structure of norstictic acid production and few significant associations between genetic clusters and the occurrence of norstictic acid. All frequently distributed haplotypes display differences in norstictic acid content. The few associations at the population level are most likely a by-product of spatial genetic structure, because norstictic acid was expressed only in individuals from the Mediterranean-Central Asian part of the study area. We conclude that the production of norstictic acid in the C. aculeata group is most likely triggered by the environment (climate, edaphic factors, associated symbionts). Cetraria steppae might be a different evolutionary lineage restricted to warm temperate regions but it is not uniquely characterized by the presence of norstictic acid.

Western North America is the global centre of diversity for Letharia, a distinctive and cryptically diverse genus of lichenized fungi belonging to the Parmeliaceae. The genus is characterized by a shrubby, fruticose habit and presence of vulpinic acid. Previous studies using multiple fungal nuclear loci revealed the existence of two distinct species-level lineages within the traditional concept of L. vulpina and four such lineages within L. columbiana. Here we use molecular sequence data in an attempt to settle long-standing taxonomic issues in the genus. Our results confirm the widespread existence within L. vulpina s. lat. of two distinct species-level groups, each forming a mutually exclusive partnership with a separate algal clade within Trebouxia jamesii s. lat. Accordingly, we formally describe the segregate species L. lupina sp. nov. Our results also support the evolutionary independence of four candidate species previously circumscribed from L. columbiana s. lat. One of these lineages, L. ‘gracilis’, has already received species recognition as L. gracilis, while a second, L. ‘lucida’, is epitypified here against L. columbiana s. str. Based on results from species delimitation analyses under the multispecies coalescent model, the two remaining lineages, L. ‘barbata’ and L. ‘rugosa’, also warrant formal taxonomic recognition; however, we refrain from describing these species pending additional studies of diagnostic characters, ecological preference, and distributions.

Rhizocarpon quinonum McCune, Timdal & Bendiksby is described as a new species from two sites in Katmai National Park, south-western Alaska, in a suboceanic climate near the limit of trees on the Alaska Peninsula. Most similar in external appearance to R. arctogenum, R. bolanderi, R. leptolepis, and R. rittokense, the species is distinguished by the presence of an anthraquinone as a major substance. Mature apothecia are unknown, but ITS sequences are most similar to those of R. copelandii and R. jemtlandicum, although those species differ greatly in morphology from R. quinonum.

The genus Rinodina (Physciaceae), with approximately 300 species, has been subject to few phylogenetic studies. Consequently taxonomic hypotheses in Rinodina are largely reliant on phenotypic data, while hypotheses incorporating DNA dependent methods remain to be tested. Here we investigate Rinodina degeliana/R. subparieta and the Rinodina mniaraea group, which previously have not been subjected to comprehensive molecular and phenotypic studies. We conducted detailed morphological, anatomical, chemical, molecular phylogenetic and species delimitation studies including 24 newly sequenced specimens. We propose that Rinodina degeliana and R. subparieta are conspecific and that chemical morphs within the R. mniaraea group should be recognized as distinct species. We also propose the placement of the recently described genus Oxnerella in Physciaceae.

Hypogymnia papilliformis McCune, Tchabanenko & X. L.Wei is described as a new species of lichenized fungus from the Primorsky region of Russia and Shaanxi Province in China. It is a relatively rare species from mixed conifer-broadleaved forests in suboceanic climates, in mountainous areas at elevations of 600–1500 m. Most similar to H. delavayi, the species are distinguished by branching pattern and chemistry. Hypogymnia papilliformis is predominantly isotomically branched while H. delavayi usually develops subpinnate branching. The ceiling of the lobe cavity is mid brown to dark brown in H. papilliformis, while the ceiling is often pale brownish or white in H. delavayi. Also, H. papilliformis lacks 3-hydroxyphysodic acid, and thus has a K– medulla, while H. delavayi always contains 3-hydroxyphysodic acid as a major substance and is thus K+ slowly reddish brown. We provide a key to the six esorediate Hypogymnia species known from the Russian Far East.

In continuation of our ongoing revisionary studies on the lichen family Graphidaceae from India, a treatment of 25 species of the lichen genera Fissurina and Hemithecium from India is presented. In our earlier work on the lichen genus Fissurina, 16 species were reported from India. In the present study, 17 additional species of Fissurina from India are recognized. Nine species, viz. Fissurina andamanensis, F. disposita, F. immersa, F. indica, F. microcarpa, F. nicobarensis, F. simplex, F. sporolata, and F. submonospora, are described as new to science. Seven species, viz. Fissurina canlaonensis, F. cingalina, F. comparimuralis, F. monospora, F. nitidescens, F. rubiginosa, and F. subnitidula, are recorded for the first time from India. One species, Fissurina sp. 1, is recorded but not formally described as new due to scanty material. Eight species in the lichen genus Hemithecium, including three new species, viz. H. kodayarense, H. longilirellatum, H. verrucosum, and five new combinations, viz. Hemithecium andamanicum, H. flabillatum, H. flavoalbum, H. flexile, and H. norlabiatum, are also recognized in the present work. A revised key for the identification of all 33 species of Fissurina and 26 species of Hemithecium so far known from India is provided.

A new isidiate, xanthone-producing species, Rinodina chrysidiata, is described and compared in detail with R. xanthophaea, a species with which it co-occurs in eastern Asia. The two species have an identical chemistry but are clearly separated by their differing lichenized diaspores, thallus morphology and ascospore type.

Population genetics investigates the distribution of genetic variation in natural populations and the genetic differentiation among populations. Lichen-forming fungi are exciting subjects for population genetic studies due to their obligate symbiosis with a green-algal and/or cyanobacterial photobiont, and because their different reproductive strategies could influence fungal genetic structures in various ways. In this review, first, I briefly summarize the results from studies of chemotype variation in populations of lichen-forming fungi. Second, I compare and evaluate the DNA-based molecular tools available for population genetics of lichen-forming fungi. Third, I review the literature available on the genetic structure of lichen fungi to show general trends. I discuss some fascinating examples, and point out directions for future research.

Anomomorpha elegans, a new species characterized by lirelline ascocarps, dark reddish brown, pruinose disc, bowl shaped exciple composed of elongate hyphae, hymenium inspersed with crystals, muriform ascospores and salazinic acid in the thallus, is described from India.

The new species Parmeliella subfuscata A. Dube & Makhija, belonging in the P. mariana group, is described. It is recognized by its squamulose, loosely attached, spreading, brownish thallus with cylindrical, branched isidia, indistinct, black prothallus of slightly projecting rhizohyphae, and its apothecia with an unusual, fresh green coloured epithecium and proper exciple. It is so far known only from the type locality in Maharashtra, India.

A new Mediterranean species, Waynea cretica, is described. The species is so far known only from Crete (Greece). Waynea cretica has flat to scarcely ascending squamules, an upper cortex being a paraplectenchymatous eucortex, and long, narrow, acicular ascospores with (5–)7 septa. The new taxon is compared with the hitherto known species of Waynea.

Topeliopsis darlingtonii A. Frisch & Kalb and Topeliopsis elixii A. Frisch & Kalb from Australia and Topeliopsis meridensis Kalb & A. Frisch from Venezuela are described as new species. Thelotrema decorticans Müll. Arg. and Ocellularia subdenticulata Zahlbr. are transferred to Topeliopsis and are the correct names for T. corticola Kalb and T. vezdae Kalb, respectively. A revised key of the genus Topeliopsis is presented. Ascoconidia, produced in old ascospores of T. elixii, are described for the first time for the Thelotremataceae.

Schaereria dolodes (Nyl. ex Hasse) Schmull & T. Sprib. comb. nov., an epiphytic lichen species known from western North America was originally described as a member of the genus Lecidea sensu lato. However, its morphology is very characteristic of the genus Schaereria Körb. Here, we lectotypify the species and propose its placement in the latter genus. It is also reported as new to Canada from British Columbia.

A corticolous species, Anisomeridium flavovulcanus, is described. It has so far been found in the Carribean and Pacific lowland rainforests of Costa Rica, where it is a frequent lichen in the understorey. This conspicuous lichen is characterized by large conical conidiomata, which release a yellow conidial mass at the apex. Dimorphic conidia occur in the same conidiomata: 1-septate microconidia and thick walled globose macroconidia. Ascomata were found only twice; the inconspicuous perithecia are hemispherical, semi-emergent with an apical ostiole, the asci are cylindrical with a cruciform ocular chamber and the ascospores are uniseriately arranged.

Lecidea hercynica Hauck & Schmull is described as a new species from Germany. It is characterized by a poorly developed or bullate to verrucose, areolate thallus on whitened spots of the substratum, numerous plane to yellowish brown to black, convex apothecia with a persistent margin, Micarea type-like asci, and by the presence of atranorin and protocetraric acid. It does not belong to Lecidea s. str., but is provisionally placed in Lecidea s. lat. until a taxonomic treatment of the whole group has been carried out. Lecidea hercynica is widespread in high-elevation forests of Picea abies in the Harz Mountains, where it grows preferably on decorticated wood in open situations.