The activity concentration of 131I, 134Cs and 137Cs radionuclides in lichens was traced one and a half months after the Fukushima nuclear accident. The samples were collected in Tsukuba City, which is located c. 170 km south of the Fukushima Daiichi nuclear power plant (NPP). The activity concentrations differed depending on species and habitat. For example, the maximum activity concentration of 137Cs was 22596 Bq kg–1 dry weight in Physcia orientalis (collected from the trunk of Zelkova serrata on 30 June 2011), and 1928 Bq kg–1 in Hyperphyscia crocata (from the trunk of Quercus myrsinaefolia collected on 8 March 2012). The activity concentration of 137Cs in Dirinaria applanata and Phaeophyscia spinellosa growing on vertical habitats decreased by c. 50% within a year, indicating radionuclides might have been washed off by rain. The radionuclides were apparently derived from the Fukushima NPP accident because: 1) one specimen collected at the same place one year before the accident did not contain radionuclides, 2) high activity concentrations of radionuclides were detected after the accident, 3) 131I, which has a short half-life of 8 days, was detected one and a half months after the accident, and 4) the ratio of 134Cs/137Cs in lichens was 0·90–0·98 on 26 April 2011, which is consistent with the values reported for radiocesium from the Fukushima NPP accident.

Removing lichen substances from dry lichen thalli using pure acetone is the least detrimental method. Measurements of properties strictly related to the photobiont, such as chlorophyll a fluorescence (ChlaF), are frequently used to verify acetone toxicity but they cannot reveal possible damage accumulated at the whole thallus level. Here, measurements of ChlaF have been integrated with others concerning the status of cell membranes and photobiont population (potassium leakage, malondialdehyde and photosynthetic pigment content). Dry thalli of Flavoparmelia caperata, Parmotrema perlatum and Xanthoria parietina were subjected to sequential acetone washings according to standard protocols. Membrane permeability was assessed before and after the washing treatment, and after a recovery period of 48 hours. Measurements of ChlaF were taken in a parallel experiment. Acetone washings increased potassium leakage in all the species from 3·9 to 6·6 times greater than the control level. After recovery, only P. perlatum returned to the control level. ChlaF was affected only in F. caperata, with a 20% decrease in Fv/Fm which had not fully recovered after 48 hours. There was neither an increase in lipid peroxidation of membranes nor a change in the photosynthetic pigment content. The sensitivity of F. caperata to this method and the impact of the results on its future application are discussed.

Cyanobacteria symbiotic with 17 members of the Lichinaceae and Heppiaceae were brought into unialgal culture and their free-living characteristics examined. A diversity of cyanobacterial types was observed; this diversity was much greater than that reported in the literature. Both the in situ identification of cyanobionts and their role as an aid to the identification of these lichens are questioned.

After a brief historical survey of the developments of vegetation science in general, and of lichen community studies in particular, this paper presents critical comments on some of the main methodological problems in the study of lichen vegetation, with particular regard to the phytosociological approach. It is suggested that in the description and classification of lichen communities lichenologists should avoid the inflation of community names that characterize the present state of the phytosociology of phanerogamic vegetation. This can be accomplished on the basis of a sound methodological approach, where the use of numerical methods can play a major role.

Four species of corticolous lichenized and non-lichenized ascomycetes are described from a tropical lowland rainforest in southern Venezuela: Mycomicrothelia xanthonica Komposch, Aptroot & Hafellner along with the closely related M. macrocarpa Komposch, Aptroot & Hafellner (Arthopyreniaceae), Pseudopyrenula cryptotheca Komposch, Aptroot & Hafellner (Trypetheliaceae), and Ancistrosporella psoromica Komposch, Aptroot & Hafellner (Opegraphaceae). Descriptions and illustrations are presented and the relationships of the taxa discussed. In addition, the following new combination is proposed: Ancistrosporella curvata (Aptroot) Komposch (Opegrapha curvata Aptroot). Ancistroporella G.Thor is regarded as typographical error and corrected to Ancistrosporella.

The diversity of pendulous Usnea species in tropical South America (Bolivia, Brazil, Colombia, Ecuador, Paraguay, Peru and Venezuela) and the Galapagos Islands is discussed with reference to 23 species. Usnea crenulata Truong & Clerc is newly described. Usnea articulata, U. deformis, U. dimorpha, U. geissleriana, U. merrillii, U. perhispidella, U. sanctaeritae, U. subflammea and U. transitoria are newly reported for South America. Modern descriptions are provided for Usnea amabilis, U. arthroclada, U. dodgei, U. humboldtii and U. regia. We propose to reject the synonymy of U. hesperina with U. schadenbergiana, and the valid name for U. hesperina is therefore U. subgracilis. Distinct patterns of unidentified triterpenoids have been detected by thin-layer chromatography and are used to characterize several species within this group. The morphology, branch anatomy, chemistry, ecology and distribution of each species are given, together with an identification key.

Cladonia is one of the largest lichen-forming ascomycete genera. It was formerly divided into ten sections, three of which, Crustaceae (Cladina), Tenues, and Impexae, are called the reindeer lichens. While previous studies have elucidated the relationships between species and sections, they often examined only one or a few specimens of each species in the analysis. This study examined the monophyly of selected members of sections Crustaceae, Tenues, and Impexae and their relationships in the genus Cladonia using the internal transcribed spacer region of the nuclear ribosomal DNA (ITS rDNA) and the mitochondrial small subunit gene of the mitochondrial ribosomal DNA (mtSSU). The phylogenetic tree contained four clades, two representing species in section Impexae, one representing species that belong to sections Crustaceae and Tenues, and one clade with C. arbuscula and related species. Five of 22 species, C. pycnoclada, C. stellaris, C. evansii, C. ciliata and C. subtenuis, showed monophyly in the phylogenetic tree; some of these 5 species have been shown previously to be monophyletic. The thallus branching pattern was interpreted as an important heritable character using the mtSSU network. Three duplets of paraphyletic species were further examined using ITS rDNA haplotype networks and AMOVA analysis. The results for the species duplets showed some mixing of haplotypes but the AMOVA analysis provided support for species separation within the duplets. While the evidence supports distinct species, further study is needed to conclusively show separate species in these duplets.

Recent fieldwork carried out for the study of the lichen flora in the Upper Douro region (north-east Portugal) has resulted in a remarkable collection of Peltula specimens, including one new species (Peltula lobata J. Marques, M. Schultz & Paz-Berm.), three new species records for mainland Europe [Peltula bolanderi (Tuck.) Wetmore, Peltula farinosa Büdel and Peltula zahbruckneri (Hasse) Wetmore] and seven species new for mainland Portugal, that are reported here with a notes on their morphology and currently known distribution. The new species Peltula lobata is differentiated from any other known Peltula species by its thallus shape and size, presence of large, sessile apothecia with widely opened discs and by a complete absence of soredia. Identical specimens were also obtained from the nearby locality of Siega Verde in the province of Salamanca, and from the southern locality of Abla in the province of Almeria, both in Spain. New insights into the morphological diversity of Peltula euploca and Peltula bolanderi are also provided. The region is revealed to be a hotspot for Peltula diversity and a very promising area for further research on the morphological and molecular variation among the former species. A revised key to European species of the genus is also presented.

Two new species, Malmidea pallidoatlantica and Malmidea sulphureosorediata, are described from NE Brazil. The first is close to M. atlantica but differs by the hyaline or pale hypothecium. The second species is a bright golden yellow sorediate crust which is assigned to the genus Malmidea because it contains the same anthraquinone pigment as M. atlantica and M. pallidoatlantica. The three species together could be referred to as the Malmidea atlantica group. Both new species were found in Mata Atlântica fragments. Malmidea sulphureosorediata was found in the Serra da Jibóia, a mountain range with a maximum elevation of 800 m, in a transitional area between the Atlantic forest and Caatinga vegetation in Bahia State. Malmidea pallidoatlantica was found in Mata do Crasto, one of the most important Atlantic forest remnants in Sergipe. It is a well-preserved Mata Atlântica relict of c. 700 hectares, at sea level.

The new lichen genus Myochroidea is described to accommodate four species of the Lecidea leprosula group. Myochroidea is characterized by a crustose, areolate, minutely crenate to almost coralloid or indistinct, grey-brown to olive-brown thallus, reddish brown apothecia with an often persistent margin, moderately branched and anastomosing paraphyses with often swollen, pigmented apical cells, asci of the Micarea-type, and colourless, one-celled, fusiform to broadly ellipsoid ascospores. The new combinations Myochroidea leprosula (Arnold) Printzen, T. Sprib. & Tønsberg comb. nov., M. porphyrospoda (Anzi) Printzen, T. Sprib. & Tønsberg comb. nov., M. rufofusca (Anzi) Printzen, T. Sprib. & Tønsberg comb. nov. and the new species M. minutula Printzen, T. Sprib. & Tønsberg are published. Lecidea porphyroplaca Hinteregger & Poelt is a synonym of M. rufofusca. Descriptions of the four species and an identification key are provided. Myochroidea leprosula and M. rufofusca are reported as new to North America.

The crustose lichen Lecanora conizaeoides has declined markedly around London with progressively diminishing sulphur dioxide pollution of the air since the 1960s. To identify the immediate causes of its decline, we applied S in the form of bisulphite (0·2 & 2 mM) and sulphate (2 mM), and N as nitrate (2 mM) to relict colonies of the lichen on beech trunks in a plantation in Windsor Forest. Growth of the lichen was monitored by estimating changes in percentage cover. By the end of a 25-month period of two-weekly treatments, all the chemical treatments had resulted in significant decreases in cover of L. conizaeoides compared to distilled water controls, with the 2 mM bisulphite causing the greatest loss. Bark surface pH was also lowered by the chemical treatments, but most by the 2 mM bisulphite applications. Similar results were obtained in two laboratory experiments where the nutrient applications were repeated under a controlled environment and thallus area monitored photographically. No evidence was obtained to support the hypothesis that growth of L. conizaeoides is stimulated by an elevated sulphur supply. We conclude that the disappearance of the lichen is linked to gradual increase in bark pH caused by the combined effects of a marked reduction in SO2 emissions and rising emissions of NH3.

The present treatment shows that the lichen family Trypetheliaceae is an important component of lowland and montane tropical forests in Bolivia. A total of 75 species are currently recognized in Bolivia, of which 24 are new to science and a further 37 are reported for the first time from the country. The following species are described: Architrypethelium penuriixanthum Flakus & Aptroot sp. nov. that differs from A. hyalinum in the lack of lichexanthone in the thallus; Astrothelium amylosporum Flakus & Aptroot sp. nov. that differs from A. subdisjunctum in having 8-spored asci and amyloid ascospores; A. bullatum Flakus & Aptroot sp. nov. that differs from A. megaspermum in having a bullate thallus, a clear hamathecium, 8-spored asci and smaller amyloid ascospores; A. carrascoense Flakus, Kukwa & Aptroot sp. nov. that differs from A. meristosporum in having broader ascospores without distinctly thickened median septa, an unidentified xanthone as major substance, and mostly eccentric ostioles; A. elixii Flakus & Aptroot sp. nov. that differs from all other Astrothelium species in the presence of lichexanthone in the outer layer of thallus and pseudostromata and isohypocrellin inside the pseudostromata, and muriform ascospores; A. inspersotuberculosum Flakus & Aptroot sp. nov. that differs from A. tuberculosum in having an inspersed hamathecium; A. megaeneum Flakus & Aptroot sp. nov. that differs from A. croceum in having a thallus covered by parietin, and mostly fused ascomata with intermediate, fused to separated ostioles surrounded by a common ostiolar area; A. neodiplocarpum Flakus, Kukwa & Aptroot sp. nov. that differs from A. diplocarpum in the absence of medullary pigment and in the amyloid ascospores; A. nigrocacuminum Flakus, Kukwa & Aptroot sp. nov. that differs from A. megochroleucum in having fused, eccentric ostioles and black (UV−) tops of the pseudostromata; A. pallidoflavum Flakus & Aptroot sp. nov. that differs from A. cinnamomeum in having wider ascospores; A. pyrenuliforme Flakus & Aptroot sp. nov. that differs from A. ecuadoriensis ecuadoriense in having shorter ascospores and in the presence of pseudocyphellae; A. subscoria Flakus & Aptroot sp. nov. that differs from A. scoria in having non-aggregated ascomata; A. variabile Flakus & Aptroot sp. nov. that differs from A. ochroleucoides in the longer ascospores; Bathelium boliviense Flakus & Aptroot sp. nov. that differs from B. lineare in the presence of isohypocrellin inside the pseudostromata; B. flavostiolatum Flakus & Aptroot sp. nov. that differs from all other Bathelium species in the presence of lichexanthone near the ostioles (tops of pseudostromata UV+ yellow) and an orange (K+ carmine red) pigment inside the pseudostromata, the absence of lichexanthone in the thallus, an inspersed hamathecium, and 13–17-septate ascospores; B. inspersomastoideum Flakus & Aptroot sp. nov. that differs from B. mastoideum in having an inspersed hamathecium; B. mirabile Flakus, Kukwa & Aptroot sp. nov. that differs from other Bathelium species in the pseudostromata containing isohypocrellin inside and parietin outside; B. pruinosum Flakus, Kukwa & Aptroot sp. nov. that differs from Astrothelium ochroleucoides in having 8-spored asci, shorter ascospores, an inspersed hamathecium, and an unidentified anthraquinone (orange pigment K+ carmine red) inside the pseudostromata; Constrictolumina chiquitana Flakus, Kukwa & Aptroot sp. nov. that differs from other known Constrictolumina species in having brown and 1-septate to submuriform ascospores; Dictyomeridium lueckingii Flakus & Aptroot sp. nov. that differs from D. proponens in having smaller and less septate ascospores; Polymeridium xanthoexcentricum Flakus & Aptroot sp. nov. that differs from P. alboflavescens in having mostly eccentric ostioles; Pseudopyrenula flavosuperans Flakus & Aptroot sp. nov. that differs from P. superans in having a hamathecium inspersed with yellow oil globules; Trypethelium astroideum Flakus & Aptroot sp. nov. that differs from T. subeluteriae in having K+ carmine red pseudostromata containing parietin inside and black tops with an additional unidentified anthraquinone (rust-red pigment K+ purple, UV−) on the outside, partly fused ostioles, and larger ascospores; and T. xanthoplatystomum Flakus & Aptroot sp. nov. that differs from T. platystomum in the presence of lichexanthone in the thallus.

The coelomycete Acaroconium punctiforme gen. sp. nov. is described from four members of the lichen-forming family Acarosporaceae, three species of Acarospora and Sarcogyne regularis. The new fungus is characterized by pycnidial conidiomata with a distinct ostiolar collar, enteroblastic conidiogenesis, and the production of simple brown conidia. The separation of the fungus from other somewhat similar pycnidial fungi growing on lichens and plant material is discussed.

Lecanora symmicta var. sorediosa Westman, a soraliate, yellow, crutose lichen frequently found on wood substrata along the sea shores in the arctic and boreal regions of the northern hemisphere, is now generally accepted as a distinct species, and has recently been provided with a new name: Lecanora arae-frigidae R. Sant. Besides usnic acid it contains zeorin, thiophanic acid and two accessory xanthones. The Finnish material of L. symmicta (Ach.) Ach. examined for comparison differs having thiophanic acid inconstant as well as three unknown substances, while lacking one of the xanthones. One specimen of L. orae-frigidae from the White Sea coast in Karelian A. S. S. R. was growing with a small thallus of Lecanora grantii Magnusson, a new record of the latter species for Europe.

Thirteen isidiate taxa in the Teloschistales are briefly discussed, i.e. Letrouitia corallina (Müll. Arg.) Hafellner, L. leprolyta (Nyl.) Hafellner, Caloplaca bassiae (Ach.) Zahlbr., C. granulosa (Müll. Arg.) Jatta, C. herbidella (Hue) H. Magn., C. isidiigera Vězda, C. isidiosa (Vainio) Zahlbr., C. littorea Tavares, C. namibensis Kärnef., C. ochraceofulva (Müll. Arg.) Jatta, C. verruculifera (Vainio) Zahlbr., Xanthoria domogledensis Veˇzda and X. isidioidea (Beltr.) Szat. The presumed origins and affinities of these taxa, which are also often fertile, are discussed. The role of isidia in reproduction and dispersal, and the justification of specific status in some of these taxa is questioned.

A survey aimed at studying the effects of hydrogen sulphide (H2S) on epiphytic lichen vegetation was carried out at Acquapassante (Mt. Amiata, Central Italy). In 1992, lichen vegetation was surveyed using a sampling grid often units, on 18 chestnut trees along a transect from a chimney emitting H2S to c. 200 m in the direction of the prevailing winds. A Lichen Biodiversity Index (LBI) was calculated as the sum of the frequencies of all species present within the grid. The same survey was repeated five years later. Concentration Analysis was applied to describe the data structure, and Procrustes Analysis was used to verify the congruence between the ordinations of 1992 and 1997. The statistically significant linear and non-linear regressions found between environmental variables (distance of relevés from the chimney, bark pH, lichen biomass of selected foliose and fruticose species, total sulphur content of Evernia prunastri, Hypogymnia physodes, Parmelia sulcata and Ramalina fastigiata) and the position of the relevé points on the ordination axes suggest that species distribution along the transect is related to differences in H2S tolerance. However, some crustose species (Lecanora cf. conizaeoides, L. saligna and Scolkiosporum umbrinum) should be probably excluded from the computation of the LBI for monitoring purposes, as their optimum is in the immediate vicinity of the H2S source.

The following new combinations are made: Anema cernohorskyi (Servít) Henssen, A. prodigulum(Nyl.) Henssen, Cryptothelelaatokkaënsis (Vainio) Henssen, C. rhodosticta (Taylor) Henssen, Gonohymenia heppii (Müll. Arg.) Henssen, G. iodopulchra (Crozals) Henssen, G. minnesotensis (Fink) Henssen, G. polyspora (Magnusson) Henssen, G. schleicheri (Hepp) Henssen, Metamelanea caesiella (Th. Fr.) Henssen, Paulia myriocarpa (Zahlbr.) Henssen, P. pyrenoides (Nyl.) Henssen, P. schroederi (Zahlbr.) Henssen, Peccania arabica (Müll. Arg.) Henssen, P. teretiuscula (Flagey) Henssen, P. tiruncula (Nyl.) Henssen, Pterygiopsis coracodiza (Nyl.) Henssen, P. umbilicaia (Vezda) Henssen, Thelignya groenlandica(Dahl) Henssen, T. Hgnyota (Wahlenb.) P. M. Jørg. & Henssen, Thyrea pachyphylla (Müll. Arg.) Henssen, T.pachyphylla var. laxa (Müll. Arg.) Henssen. The following new names (one as a new species) were found necessary: Pyrenopsis haematina P. M. Jørg. & Henssen and Thyrea confusa Henssen. New synonyms are given for several names. The world-wide distribution of the genera Phloeopeccania and Pterygiopsis is mentioned.

The systematic position of the lichen genus Heppia in the order Lichinales was investigated. 18S rDNA sequence data were analyzed using a Bayesian approach to infer phylogeny using Markov chain Monte Carlo methods. The Lichinales are divided at family level into the sister groups Lichinaceae and Peltulaceae. The genus Heppia forms a highly supported clade in the family Lichinaceae. It is shown that the genus Heppia is morphologically well circumscribed within the Lichinaceae. As a nomenclatural consequence, the family name Heppiaceae is placed into synonymy under the older name Lichinaceae.