We studied lichen communities along forest edge-to-interior gradients on opposite sides of a major highway and along a remote lakeshore in central North Carolina, U.S.A., to investigate highway pollution effects on this sensitive ecosystem component. At each site we sampled lichens on trees at 10 m intervals along each of five parallel transects established at the forest edge and at 25, 60, 100, and 150 m into the forest in the highway sites, with a similar layout along a nonlinear lakeshore in a similar forest type, from which transect distances from the forest edge were estimated using average tree distances from the nearest shoreline. Lichen communities were inventoried on tree trunks from the base up to 1.5 m height, then compared both among and within sites. Species richness was highest in the control site, and did not differ between the two highway sites. The highway sites were more similar to one another than either was to the control site, based on Bray-Curtis similarity indices. No associations were detected among sites and sampled lichen biotic components in terms of growth form, photobiont type or reproductive mode. In the highway sites, total transect species richness increased from the forest edge to 150 m distant. In the control site, species richness decreased from the forest edge to the most distant transect. Findings suggest a negative effect of highway pollution on species richness of lichen communities, but not on species composition by habit, photobiont type or reproductive mode. Despite the elevated NO_x concentrations recorded along the highway, known nitrophilous species were largely absent, suggesting that other factors, including other pollutants, were affecting community structure near the highway.

Two new non-lichenized Arthonia are described from the branches and wood of pine trees (Pinus spp.) in the Coastal Plain of southeastern North America. Arthonia samdykeana is a characterized by its lack of photobiont, large irregularly shaped ascomata, and 6–9(–10–12)-celled ascospores that are macrocephallic. Arthonia gutberletiana is characterized by its lack of photobiont, black circular apothecia with persistent margins, hyaline 2-celled ascospores and occurrence on pine wood.

Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and forest health. Stand age has been implicated as a key factor in driving epiphytic species diversity and community composition. However, understanding the influence of substrate age, independent of the many confounding variables that affect live and dead wood substrates in a forest habitat, can be difficult. To test the hypothesis that substrate age has distinct effects on lichen community assembly independent of surface area, we sampled communities of calicioid lichens and fungi growing on wooden buildings that ranged from 2 to 82 years old. We found a total of 17 species, with a strong positive correlation between species richness and substrate age. We also tested the effects of surface area on species richness and found no relationship between the two variables. Our results indicate that substrate age influenced community composition; non-lichenized calicioid species acted as early colonizers and six calicioid species were recorded only on the oldest substrate. Old-growth associate species were found on substrates of varying ages, implying that additional variables may also be responsible for the colonization of old-growth associate species.

Buellia numerosa and B. subnumerosa are described as new from Japan. These two corticolous species share common morphological characters: whitish, smooth to rimose thallus; adnate apothecia; flat, epruinose disc; dispersa-type proper exciple; numerous ascospores per ascus; and Buellia-type ascospores. In addition, they share chemical characters: presence of fumarprotocetraric acid and atranorin. They are clearly distinguishable from previously-described Buellia species based on their ascospore numbers and metabolites, and from each other by the number of ascospores per ascus and characters of the asci. Buellia numerosa has 20–64 ascospores per ascus while B. subnumerosa produces 8–36. Also, brown overmature asci are always found in B. subnumerosa, but not in B. numerosa. A phylogenetic analysis based on the ITS region confirmed that they should be recognized as two different species.

Lichens have been a difficult group for botanists to understand. Only in the 20^th century did they find their correct position among the fungi. This paper outlines the long and rather complicated course from Theophrastos, the first person to use the term lichen (about 300 B.C.) to the molecular evidence by Gargas and coworkers in 1995 that proved lichens to belong among the fungi. It was, however, not the first time this classification was proposed. The first to formally include lichens in the fungi was J. B. Payer in 1848, and Persoon had already around 1800 suggested this in a letter to Acharius. It then took nearly 200 years to become a generally accepted idea, but during that process many important observations, still worthy of attention, were made.

A bryophyte inventory in the Serra do Aracá, Amazonas State, a sandstone tepui in northern Brazil (Guiana Shield), yielded 169 species in 68 genera and 29 families. Seven species are new to Brazil and 26 are new records for the north of the country. The Serra do Aracá holds 28% of the total number of bryophyte species recorded for northern Brazil. The most common families were Lejeuneaceae (31% of all species), Lepidoziaceae (14%), and Plagiochilaceae (6%) for liverworts, and Sematophyllaceae (7%), and Dicranaceae and Calymperaceae (6% each) for mosses. Together these six families accounted for half of the genera and almost 69% of the species collected. Seven distribution patterns were recognized, with species showing Tropical American distributions (49%). About 50% of the species are widespread in the country, nine being endemic to Brazil, and four restricted to the northern region. The results represent an increase in knowledge of the Brazilian bryoflora, being relevant for the conservation of bryophyte diversity in the Amazon Forest.

Oxystegus daldinianus (De Not.) Köckinger, O.Werner & Ros, a species recently identified from the Alps of central Europe, is reported as new to the New World from collections in North Carolina, U.S.A., with a key to species of the genus in North America. A refugial explanation is proffered for this montane disjunction. Species distinctions in Oxystegus and evolutionary relationships are evaluated with two tools—an analytic key, and support measured with sequential Bayes-based information theory.

The following corrections and amendments are made to the 2016 classification of lichenized fungi published in the previous issue of this journal. Four families are added: Harpidiaceae (Pezizomycotina incertae sedis), with the two genera Euopsis and Harpidium; Pleomassariaceae (Pleosporales), with the genus Splanchonema; Squamarinaceae (Lecanorales), with the two genera Herteliana (moved from Ramalinaceae) and Squamarina (moved from Stereocaulaceae); and Trichosphaeriaceae (Sordariomycetes: Trichosphaeriales), with the genus Cresporhaphis. The following previously overlooked genera are also added: Allophoron (Pezizomycotina incertae sedis), Cresporhaphis (Trichosphaeriaceae), Gabura (Arctomiaceae), Julella (Trypetheliaceae), Knightiella (Icmadophilaceae), Porpidinia (Lecideaceae), Protoroccella (Roccellaceae), Psoromidium (Pannariaceae) and Tremotylium (Arthoniales incertae sedis). The classification is adjusted for four genera: Asteroporum (moved from Pezizomycotina incertae sedis to Dothideomycetes incertae sedis), Eremastrella (moved from Psoraceae to Lecideaceae), Hosseusia (moved from Pannariaceae to Lecanoromycetes incertae sedis) and Joergensenia (moved from Lecanorales incertae sedis to Pannariaceae). Further, the following overlooked generic synonyms are listed: Buscalionia (= Marcelaria [nom. cons. prop.]), Degeliella (= Psoromaria), Dirinastrum (= Buellia), Gymnographa (= Phaeographis), Kroswia (= Fuscopannaria), Marfloraea (= Lepra), Medusulina (= Fissurina), and Phaeographina (= Pliariona); the genus Anapyrenium is discussed as a potential synonym of Thelomma. Species numbers are adjusted for nine genera: Austrella (Pannariaceae; 3 spp.), Icmadophila (Icmadophilaceae; 5 spp.), Lepidocollema (Pannariaceae; 23 spp.), Massalongia (Massalongiaceae; 6 spp.), Parmeliella (Pannariaceae; 70 spp.), Psoromidium (Pannariaceae; 1 spp.), Pyrgillus (Pyrenulaceae; 7 spp.), Siphula (Icmadophilaceae; 17 spp.) and Synarthonia (Arthoniales incertae sedis; 5 spp.). The fossil lichen Honeggeriella (complexa) is validated by adding MycoBank registration numbers, the validity of the genus name Pallidogramme (Graphidaceae) is discussed and confirmed, and the authorship of the name Thallinocarpon (Lichinaceae) is clarified. Several genera are (continued to be) considered non-lichenized, namely Chaenothecopsis (Eurotiomycetes: Mycocaliciales: Sphinctrinaceae), Limboria (newly lectotypified with L. constellata; Pezizomycotina incertae sedis), Naetrocymbe (Dothideomycetes: Pleosporales: Naetrocymbaceae), and Obryzum (Dothideomycetes incertae sedis: Obryzaceae); the status of the genus Pleurotrema (Dothideomycetes incertae sedis: Pleurotremataceae) is also discussed. Seven genera are corrected to have molecular data available: Adelolecia, Aspiciliopsis, Aspilidea, Crocodia, Parasiphula, Vezdaea and Xylopsora. With these corrections, the number of lichenized species is now tabulated at 19,409 and the number of fungal genera, families, and orders including lichens at 1,002, 119, and 40, respectively.