The new lichen genus Musaespora is described from Java and Papua New Guinea. It is the first known pyrenocarpous lichen genus with campylidia, and appears to belong to the Aspidotheliaceae. Three species are described, two foliicolous species from Papua New Guinea and one corticolous species from Java. In addition, a list is given of the foliicolous lichen flora of the site in Papua New Guinea, where the foliicolous Musaespora species have been found, two more new foliicolous species are described, Echinoplaca hispida and Sporopodium lucidum, and 19 species are recorded for the first time form Papua New Guinea.

Notes are provided on the genus Ramonia and its four species represented in the British Isles, including R. dictyospora sp. nov. and R. nigra sp. nov.

Two new corticolous species, Hafellia alisioae and H. gomerana (lichenized Ascomycetes, Physciaceae), collected from twigs of coastal shrubs on the Canary Islands are described. The new species are discussed in relation to other Hafellia species with similar characters. An overview and a key for 23 corticolous species of Hafellia with 2-celled ascospores is provided.

Sphaerophorus diplotypus Vainio is reported as new to mainland Africa (Tanzania). Sphaerophorus digitaius Wang-Yang & Lai is reduced to a synonym of S. diplotypus. The name Sphaerophorus dodgei Ohlsson is validated and a description of the species is given. Sphaerophorus dodgei is recorded as being widespread and common in the Valdivian rainforest of Chile and Argentina. Sphaerophorus imshaugii Ohlsson is reported as new to the North and South Islands of New Zealand. Sphaerophorus macrocarpus Ohlsson is reported as new to South America (Chile). In S. dodgei and S. macrocarpus the spore ornamentation consists of mazaedial material added to the spore wall after the spores have been released from the asci. Concentric bodies occur in young ascospores of S. macrocarpus. A protocetraric-acid-deficient strain of S. microsporus Ohlsson is reported for the first time. Sphaerophorus tibellii Wedin, from northern New Zealand, is described as new.

Five populations of the circumpolar Arctic-alpine lichen species Cetraria nivalis were sampled along a latitudinal gradient from the temperate to the Arctic climatic zone. The populations were compared with respect to their CO2 exchange, water relations and morphology/anatomy. Provenances from places along this latitudinal gradient were transplanted in 1983/84 to a site near the Scientific Research Station in Abisko, to see whether they are identical with plastic acclimation ability or whether they represent different ecotypes. The five populations represent two major geographical groups, a ‘southern’ and a ‘northern’ one, with respect to some morphological and anatomical features, chlorophyll content and water relations. The transplanted C. nivalis provenances showed a tendency towards increasing net photosynthetic rates with origin in the higher latitudes. The CO2 exchange response of the native populations was the reverse of this tendency although CO2 exchange was in general flexible. It is concluded that the investigated C. nivalis populations were different ecotypes because of genetic differences and a distinct seasonal plasticity. The ecotypes are interpreted as a result of isolation in different refugia during the Pleistocene.

The species of the Parmelia saxatilis complex occurring in the Iberian Peninsula were revised. Eight species are accepted, including a new species found in southern Spain, described as P. rojoi A. Crespo, V. J. Rico & Divakar. The new species, which forms a sister-group relationship with P. saxatilis s. str., is rare in the Iberian Peninsula and is restricted to higher altitudes of northern and central Spain. Parmelia rojoi differs from P. saxatilis by generally narrower isidia and a more fragile thallus. The segregation of the new species is also supported by ITS (rDNA) and Mcm7 (MS456) phylogeny and multispecies coalescent-based approaches, including StarBEAST and BP&P. Furthermore, the divergence of P. rojoi is dated back to the Pleistocene, c. 2.13 Ma. A key to the identification of species from the P. saxatilis complex with their diagnostic features is provided. All species of the complex known from Europe are also found in the Iberian Peninsula. We hypothesize that P. rojoi is a relict species that survived the Pleistocene glaciations in refugia in Spain and has been unable to extend its distributional range in postglacial periods.

Zwackhiomyces cervinae Calat., Triebel & Pérez-Ortega is described as new to science from Spain and Iran. This lichenicolous species grows on the lateral side of the squamules of Acarospora cervina, and it is characterized by its relatively large ascospores, which are brown when overmature. It is compared with several Zwackhiomyces species and with other taxa sharing some of its characters. A key to all the known species of the genus is also provided.

Lithographa serpentina Coppins & Fryday is newly described from Campbell Island (New Zealand), and is unique within its genus and order for having submuriform ascospores. Also newly described are Lithographa opegraphoides Coppins & Fryday from the Falkland Isles, Rimularia actinostoma Coppins & Fryday from Canada (British Columbia), and Rimularia austrolimborina Coppins & Fryday from southern Chile. The new combination Lithographa graphidioides (Cromb.) Imshaug ex Coppins & Fryday is made to accommodate the previously misunderstood Stigmatidium graphidioides Cromb. and the more recently described Lithographa subantarctica Hertel & Rambold. A key to all described species of Lithographa is provided.

Snow meltwater containing 36 ng ml−1 NO3−−N (raised here to between 95–101 ng ml−1 NO3−−N) and 112 ng ml−1 NH4+ −N was sprayed onto illuminated Usnea sphacelata at 2°C in a 2−1 capacity transparent perspex chamber force-ventilated with either air or O2− (and CO2−) free N2. The NO3-concentration in meltwater recirculated through a layer of U. sphacelata fell to c. 8 ng ml−1 after 1.25 h. Although the pattern of decline was broadly comparable in both air and N2, the initial rate of decline was lower in N2. When undepleted meltwater was continuously sprayed onto the lichen and the effluent collected for analysis, the lichen was found to retain 55% of the wet deposited NO3− in air but only 27% under N2. Up to 90%) of NH4+ supplied in a continuous spray of meltwater was retained by the lichen but this was affected little by O2 and CO2 deprivation.

The silicicolous lichen species, Rinodina etayoi Giralt & van den Boom, is described as new from inland localities of Fuerteventura and Lanzarote (Canary Islands). It is characterized by a crustose, whitish thallus containing atranorin, zeorin, chloroatranorin and stictic acid, hemispheric pseudolecanorine apothecia containing, a proper exciple inspersed with numerous and large oil drops, and by ascospores of the Mischoblastia-type. The joint occurrence of pannarin, stictic acid and Mischoblastia-type ascospores makes R. etayoi unique within the genus.

The study of the type and additional material of Buellia andicola, B. hypophana and B. reagens has shown that these taxa are conspecific with B. thiopoliza. Buellia thiopoliza is a muscicolous species growing at middle to high altitudes in the mountains of both hemispheres. It is easily recognized by its K+ purple-red yellow pigment mainly concentrated in the hypothecium, and by the presence of xanthones in the thallus and the apothecial tissues. The new combination Tetramelas thiopolizus is proposed. A key to all known Tetramelas species is included. The also muscicolous Buellia hypoleuca is reduced to synonymy with Phaeorrhiza sareptana var. sphaerocarpa.

The foliicolous lichens and the environmental factors at 14 stations in Catalonia were examined and the relationships between their foliicolous flora and climatic features analysed. This information could be used to predict potential sites with foliicolous lichens in areas with a Mediterranean climate. In addition, two species new to the European lichen flora (Bacidina canariensis and Fellhanera semecarpi) are recorded, and also 8 species new to the lichen and lichenicolous flora of the Iberian Peninsula (Arthonia leptosperma, Byssoloma diederichii, Chionosphaera apobasidialis, Cladosporium arthoniae, Fellhanera christiansenii, Fellhanera seroexspectata, Strigula smaragdula and Vezdaea dawsoniae).

Two new species of Pyxine with yellow medulla from saxicolous habitats are described as new to science. The new species P. punensis has an isidiate, UV+ yellow thallus with 0·3–0·6 mm wide lobes. Pyxine yercaudensis has smaller ascospores (13–16×6–7 µm), lacks vegetative propagules and lacks lichexanthone.

Molecular studies have shown that Psoromidium is well separated from Psoromaria and Degeliella, when including the type species only. The latter generic name is illegitimate and the correct name for the other species sometimes included in Psoromidium is shown to be Psoromaria versicolor (Müll. Arg.) P. M. Jørg. & H. L. Andersen, comb. nov. It is the type species of the genus Psoromaria Nyl. ex Hue. The inclusion of Degeliella rosulata in Psoromaria is unresolved, according to the molecular evidence. However, its characters (except the photobiont) match those of Psoromaria, rather than those of the other species with which it groups. So for nomenclature reasons it is transferred to this genus, as Psoromaria rosulata (P. M. Jørg. & D. J. Galloway) P. M. Jørg. & H. L. Andersen comb. nov.

Four species of the genus Graphis Adans. are described as new to science, namely G. archeri, G. invisibilis, G. lueckingii and G. paranaensis. These new species were found growing in restinga forest in southern Brazil.

The genus Japewia Tønsb. is introduced to accommodate three species including J. subaurifera Muhr & Tønsb. sp. nov. based on material from Norway, Sweden, Finland, Scotland, Canada (British Columbia) and U.S.A. (Washington). This species is closely related to Lecidea tornoensis Nyl. but is distinguished in being sorediate and by the production of lobaric acid (accessory) and acetone-soluble pigments. It grows on bark of deciduous and coniferous trees. Lecidea carrollii Coppins & P. James and L. tornoensis Nyl. are transferred to Japewia.

The new genus Sporostigma is introduced for the remarkable species Arthonia melaspora. The genus is characterized by mazaediate ascomata and dark brown ascospores. Relationships with other genera are discussed.

The nomenclature, chemistry, taxonomy, distribution and ecology of Aspicilia tuberculosa (Ach.) Laundon comb, nov., Buellia ocellata (Flotow) Körber, Pycnothelia papillaria Dufour, Rhizocarpon richardii (Lamy ex Nyl.) Zahlbr. and Rinodina aspersa (Borrer) Laundon comb. nov. are discussed. Aspicilia tuberculosa, related to A. caesiocinerea, has apparently not been collected since c. 1830 and may now be extinct. The name Buellia verruculosa has been wrongly applied and the species should be called B. ocellata. The name Pycnothelia papillaria is retained, but with a modified author citation. Rhizocarpon constrictum is a synonym of R. richardii. Rinodina fatiscens is shown to be a synonym of R. aspersa. The nomenclature of Aspicilia caesiocinerea and Rinodina atrocinerea is also considered, the latter requiring change of author citation.