Pannaria leproloma is shown to be a New Zealand endemic, and is characterized by coarse isidiomorphs/isidia, a high frequency of apothecia and the presence of two cytotoxic scabrosin esters, previously unknown from Pannariaceae, and present in 40 of the samples studied. It is not a member of the Pannaria sphinctrina group, as previously thought. It has frequently been confused with a related, finely sorediate, very sparingly fertile species, which lacks scabrosin esters in more than 99 of the specimens studied. This latter species is widely distributed both in southern South America (where it is one of the most common corticolous lichens), south-eastern areas of Australia and in New Zealand. It was originally described as Psoroma isidiosum, but had to be renamed when transferred to Pannaria, and is here named Pannaria farinosa.

New collections from inner China have revealed further species in the genus Fuscopannaria: two new species, Fuscopannaria cyanogranulosa P. M. Jørg. and Fuscopannaria obtegens P. M. Jørg. are described and Fuscopannaria subgemmascens Upreti & Divakar is reported as new to Sichuan. A key to the sorediate species of the region is provided. The first fertile specimen of Kroswia gemmascens has been discovered, much further west than previously known, showing the genus to be related most closely to Fuscopannaria despite its gelatinous, homoiomerous thallus. Some collections from the Mulu region in Borneo have added to our knowledge of the difficult lowland taxa of Parmeliella, two of which proved to be new: Parmeliella plumosella P. M. Jørg. and Parmeliella polydactyla P. M. Jørg. & Coppins, both being quite unusual in containing “violet” Nostoc as cyanobiont. There is a surprising number of Asian collections with brightly coloured medullas: red-orange material has been named several times and is correctly referred to as Parmeliella endomilta Vain. The specimens with a yellow medulla are named Parmeliella endolutea P. M. Jørg., nom. nov. A key to the brightly coloured species of Parmeliella concentrated in SE Asia is given. A new corticolous Protopannaria has been discovered in Sichuan, and is described as P. corticola P. M. Jørg.

Chrysothrix occidentalis Elix & Kantvilas, C. palaeophila Kantvilas & Elix and C. tchupalensis Elix & Kantvilas are described as new to science. In addition, the new combination Chrysothrix sulphurella (Räsänen) Kantvilas & Elix is proposed, C. granulosa G. Thor is reported for the first time from Australia (including Tasmania) and New Zealand, and C. xanthina (Vain.) Kalb for the first time from Tasmania, Norfolk Island and New Zealand. A key to the Australian species of Chrysothrix is presented. Chemical data on non-Australasian species of the genus are also provided.

The in-vitro growth rate of soredia from the epiphytic lichen species Physcia tenella was tested at different concentrations of phenols added in an in vitro experiment designed to evaluate the allelopathic effects of bark derived substances in stem flow. The conditions used were designed to resemble those found on bark of Populus×canadensis, as this tree species has been widely used for lichen mapping studies in Germany. Bark phenolic glycosides, flavonoids and tannins undergo hydrolytic decomposition in stem flow, resulting in a variety of monomeric phenolic acids, aldehydes and alcohols. Eleven phenolic substances of different biosynthetic origin in the concentration range between 10−6 M and 10−3 M in the culture medium were tested. IC50 values were calculated for each substance. Inhibition was highest for catechol, substituted phenolic glycosides, benzoic and ellagic acids, moderate for flavonoids, gallic acid, salicylic alcohol, salicylic aldehyde and low for salicylic acid. The tests show that bark phenols in natural concentrations inhibit soredial growth of the test species Physcia tenella and therefore have an influence on the growth of lichens on trees.

The new combination Lithographa skottsbergii (Zahlbr.) Fryday & Coppins is made for Enterostigma skottsbergii Zahlbr., described from the Juan Fernandez Islands off the coast of Chile. The species is known only from Chile but its geographical range is here extended to include maritime regions of south-west Chile. The distribution pattern of the Lithographa species with submuriform ascospores is also discussed.

New records of 15 Lepraria species from South America are presented. Two species are newly described from the Bolivian Andes: Lepraria achariana Flakus & Kukwa (major compounds: lecanoric, angardianic/roccellic acids and anthraquinones) and L. neojackii Flakus & Kukwa (major compounds: porphyrilic, angardianic/roccellic, cf. rangiformic acids and anthraquinone). Lepraria impossibilis, L. lecanorica and L. rigidula are reported as new for the Southern Hemisphere, L. alpina, L. aff. caesiella and L. squamatica as new to South America, and other species as new to several countries (Argentina, Bolivia, Brazil, Peru, Uruguay). In addition, two putative, undescribed species are discussed. Chemistry, ecology and general information concerning distribution of the species are presented, and the differentiation of some critical taxa discussed. A provisional key to Lepraria in South America is provided.

In this investigation we utilized parsimony and Bayesian analyses of mtSSU and nuLSU rDNA sequence datasets to show that the lichenized ascomycete genera Leptochidium and Polychidium (formerly classified in Placynthiaceae) form a well-supported monophyletic group with Massalongia (Peltigerales, Lecanoromycetes, Ascomycota). This group is also supported by morphological characteristics (ascus type, ascoma ontogeny and anatomy), but does not have a formal name on any level. We describe it here as the family Massalongiaceae. Massalongiaceae is related to a group consisting of Peltigeraceae-Nephromataceae, and Lobariaceae, but the detailed relationships within this group are not resolved with convincing support.

Eighteen species in the lichen genera Acanthothecis Clem. and Fissurina Fée (Graphidaceae) with colourless, trans-septate ascospores are recorded from India. Eight new species, namely Acanthothecis collateralis, Fissurina capsulata, F. coarctata, F. karnatakensis, F. khasiana, F. longiramea, F. taeniocarpoides and F. verrucosa, and a new variety, F. dumastioides var. salazinica, are described. Fissurina saxicola ad int., clearly distinguished from the other species is recorded, but is not formally described as new to science as the material is scanty. Acanthothecis consocians, F. globulifica, F. insidiosa and F. rugosa are reported for the first time from India. A key for the trans-septate species of Acanthothecis and Fissurina in India is provided.

The new species Megalaria allantoidea Fryday is described from the subantarctic Îles Kerguelen in the southern Indian Ocean, where it grows over terricolous bryophytes or Azorella selago cushions. It differs from all other described species of Megalaria in having large, sausage-shaped ascospores. The systematics of the genus Megalaria is reviewed, ascus structure of some previously described species revised, and the position of the new species in the genus discussed.

Genetic diversity in symbionts of the lichen Cladonia arbuscula was investigated. Forty-eight specimens of Cladonia arbuscula located within a 2 km range at Payuk Lake in Manitoba were collected. Population structure and method of symbiont transmission in C. arbuscula were inferred by examining the presence or absence of introns in the nuclear small subunit (SSU) ribosomal DNA (rDNA) of the mycobiont and restriction fragment length polymorphism (RFLP) of the internal transcribed spacer (ITS) rDNA in the photobiont. The mycobiont showed a high level of genetic variation and the photobiont a low level of variation within the small geographic range studied. An analysis of molecular variance of fungal genotypes showed significant population subdivision for the mycobiont when the data were analysed at P=0·05. No population subdivision was detected when P=0·001. The photobiont also showed no population subdivision. Photobiont genotypes did not correlate with mycobiont genotypes suggesting the symbionts were not transmitted together in the same propagule. Multiple fungal genotypes were also detected in C. arbuscula and possible explanations were discussed.

The new genus Aptrootia Lücking & Sipman is described for Thelenella terricola, an enigmatic terricolous and muscicolous, pyrenocarpous taxon known from Papua New Guinea and Costa Rica, and the new combination Aptrootia terricola (Aptroot) Lücking, Umaña & Chaves comb. nov. is introduced. Aptrootia is characterized by completely immersed perithecia with brown-black ostiolar region, surrounded by a white, cartilaginous thallus resembling that of Gomphillaceae. The hamathecium is typical of Trypetheliaceae, with thin, anastomosing paraphysoids embedded in a gelatinous matrix, but the dark brown ascospores are otherwise unknown within the family. The only known species was tentatively described in Thelenella, but hamathecium type and molecular data place Aptrootia within Trypetheliaceae.

Bacidia coprodes (Körb.) Lettau, until now treated as a synonym of Bacidia trachona (Ach.) Lettau, is resurrected. Morphological, chemical and ecological characteristics place this species close to Toninia in the Ramalinaceae, but we retain it in Bacidia because of uncertainties in the generic taxonomy of this family. Bacidia coprodes is fairly widespread on calcareous and enriched siliceous rock in Europe and eastern North America. In North America the species has also been known under the synonyms Bacidia granosa (Tuck.) Zahlbr. (basionym: Lecidea granosa Tuck.) and Bacidia pammellii (Fink) Zahlbr. (basionym: Bilimbia pammellii Fink). Morphological and chemical features, together with molecular data, suggest that B. trachona does not belong to Bacidia, but rather in the Pilocarpaceae.

In contrast to the frequently assessed macrolichens, microlichens are rarely considered in biodiversity assessments despite their high species richness. Microlichens require generally a higher species identification effort than macrolichens. Thus, microlichens are more expensive to assess. Here we evaluate if macrolichen richness can be used as an indicator of total and threatened microlichen richness. Furthermore, we tested if different sets of environmental variables (modelled climatic variables, forest structure, altitude, etc.) improve the regression models based on macrolichens only or even replace the macrolichens as predictors. Multiple linear regressions were used to model species richness of microlichens, and Poisson regressions for threatened microlichens.

On 237 forest plots (200 m2) distributed randomly across Switzerland, 77 macrolichens and 219 microlichens occurred. Macrolichen richness was positively related to the richness of microlichens (=0·27) and, in combination with threatened macrolichens as an additional predictor, also to the number of threatened microlichens (=0·14). Environmental variables alone and in different combinations explained between 0·20 and 0·41 () of the total variation of microlichen richness, and between 0·09 and 0·29 () of the total variation of threatened microlichen richness. All models based on environmental variables were considerably improved when macrolichens were included. Furthermore, macrolichen richness turned out to be the most important variable in explaining species richness of all, as well as threatened microlichens. The best models for total microlichen richness reached a of 0·56. Threatened microlichens were more difficult to model with the best model reaching a of 0·29.

We conclude that in biodiversity assessments with scarce resources, lichen sampling could be focused on the better known macrolichens, at least in many temperate lowland and mountain forests. In combination with environmental variables, reliable predictions of microlichen richness can be expected. If the focus is on threatened microlichens, however, models were not reliable and specialized taxonomists are necessary to assess these species in the field.

The effect of a copper-smelting plant on populations of Hypogymnia physodes and Tuckermanopsis sepincola was studied in the Middle Urals. A different population response was found between the two lichen species due to different life strategies. The pollution appears to decrease growth and developmental rate of H. physodes (a vegetatively reproducing strongly competitive species), resulting in a shift of population structure towards smaller, esorediate to low sorediate thalli. The background population of the sexually reproducing Tuckermanopsis sepincola consisted mainly of young, small thalli of a low fertility as a result of strong inter-species competition with H. physodes. At the polluted site, the sharp decrease in the abundance of H. physodes led to a shift in structure of the T. sepincola population towards larger and more fertile thalli. It may be concluded that T. sepincola benefits from air pollution by an indirect effect of the removal of a strong competitor, i.e. H. physodes.

Usnea is a species-rich and widespread lichenized fungal genus of well-lit parts of forest canopies (Motyka 1936, 1947; Clerc 1998). The bright greenish colour of these beard lichens reflects the presence of usnic acid in the cortex, which forms a thin, but dense sleeve around the trebouxioid photobiont in the outermost parts of the medulla. Usnic acid, a widely distributed dibenzofuran derivative produced by various mycobiont genera, strongly absorbs UV-B, but also the shortest PAR wavelengths (e.g. McEvoy et al. 2006, M. McEvoy, K. A. Solhaug and Y Gauslaa unpublished). Depending on species (Halonen et al. 1998), Usnea also contains a wide range of UV-B absorbing depsidones and depsides, though these are usually assumed to be confined to the medulla. Quantitative data on lichen compounds are rare in Usnea species, particularly with respect to the intrathalline variation.

Ecological studies are essential in understanding the response of crustose lichens to habitat dynamics and developing effective conservation strategy. While the combined response of individual crustose species within a community will be tremendously complex, the overall result of individualistic change can be simplified using trait-based analyses. In this paper we examine the response of crustose species with contrasting reproductive traits (predominantly sexual vs asexual reproduction) and which occur within a closely defined habitat (as epiphytes on the lower bole of aspen) to environmental drivers measured at two different scales, i.e. between and within aspen stands. Our results point to the important effect of tree age and subsequent shifts in bark quality (pH) on the composition of the crustose community. However, shifts in community composition putatively controlled by bark quality comprise a change from a community dominated by sexual species to a community with mostly asexual crusts. Our results suggest therefore that variation within this crustose community may be driven by the combined effects of allogenic change (tree age and bark quality) and autogenic processes that are related to a species’ adaptive life-history traits.

In order to examine genetic variation and population structure of the widespread lichen-forming ascomycete Xanthoria parietina from similar habitats, but different sites in Scandinavia, we investigated seven populations in Scania, southernmost Sweden, and compared the results with a corresponding study on Storfosna, central Norway. Sequence variations of the nuclear ribosomal DNA were used as molecular markers, for both a part of the IGS region and the complete ITS1-5.8S-ITS2 region. The amount of genetic variability observed was comparable in the two investigations. Divergence between populations in different habitats found in the previous study was also present in this study. Xanthoria parietina is genetically differentiated between habitats with no evidence of restricted gene flow between populations in the same habitat at the present spatial scale, at least at sites along the coast of Scandinavia. Differentiation between habitats is considerable at both study sites, which we attribute to restricted gene flow between habitats, i.e. habitat isolation.

In two lichen species, Hypogymnia physodes and Lecanora conizaeoides, often used as model organisms for pollution-sensitive and pollution-tolerant epiphytic lichens, respectively, the hypothesis was tested that the toxitolerance of the Trebouxia photobiont limits the tolerance of the entire lichen symbiosis. Being lecanoralean-trebouxioid associations, H. physodes and L. conizaeoides represent the most common type of lichens. Photobionts of both lichen species deriving from microhabitats with varying supply of S and heavy metals were identified using nuclear ITS nrDNA sequencing. The photobiont of L. conizaeoides was identified as T. simplex, whereas the photobiont of H. physodes belongs to an undescribed Trebouxia species, related to T. jamesii subsp. angustilobata and provisionally named as T. hypogymniae Hauck & Friedl ined. Since T. hypogymniae ined. is also known from Lecidea silacea, which is characteristic of rock and slag with high heavy metal content, a high sensitivity of this alga to pollutants is unlikely to be a key factor for the relatively low toxitolerance of H. physodes. Furthermore, the photobiont cannot be crucial for the extremely high toxitolerance of L. conizaeoides, as T. simplex is also known from pollution-sensitive lichens of the fruticose genus Pseudevernia. These findings suggest that the photobiont is not generally a key factor determining pollution sensitivity in the most common type of lichen symbiosis. The high specificity for T. simplex in L. conizaeoides in existing populations of L. conizaeoides suggest that already established thalli could be a source of photobiont cells for re-lichenization.

The effect of increasing concentrations (0·01, 0·1, 1 and 5 mg l−1) of intact (FLT) and photo-modified (phFLT) fluoranthene and the duration of exposure (1, 2, 3, 5 and 7 days) on the chlorophyll fluorescence parameters (F0, FV/FM, and ΦII) of symbiotic algae in the thalli of two foliose lichens Lasallia pustulata and Umbilicaria hirsuta was investigated. In addition the FLT concentration in thalli of both lichen species was determined and a bioconcentration factor (BCF) was calculated. The results obtained demonstrated that the concentrations of FLT and especially phFLT (1 and 5 mg l−1) applied affected primary photochemical processes of photosynthesis in the algae of both lichen species. The F0 value increased and the FV/FM and ΦII values decreased. The fluoranthene content in the thallus of both lichen species increased with increasing FLT concentration in the environment.

The foliicolous species Bacidia colchica Vězda was described from the eastern coast of the Black Sea (Vězda 1979, 1983) and is also known from SW France (Sérusiaux 1989; Sérusiaux et al. 2002) and S Italy (Puntillo 2000; Puntillo et al. 2000). However, its morphological features, such as the structure of the exciple, morphology of the paraphyses and ascus type, do not fit the current concept of Bacidia De Not. (Ekman 1996, 2001) but place this taxon in the Pilocarpaceae. The current circumscription of Pilocarpaceae is still under discussion, as well as the concept of some genera at present included in this family (Sérusiaux 1993; Lücking et al. 1994; Kalb et al. 2000; Lücking et al. 2001a; Sérusiaux et al. 2002; Andersen & Ekman 2005). In particular, the position of B. colchica should be in Fellhanera Vězda (Vězda 1986; Lücking et al. 1994; Sérusiaux 1996; Lücking 1997). Although several recent works have dealt with the European species of the genus Fellhanera (Sérusiaux 1996; Aptroot et al. 1998; Sparrius & Aptroot 2000; Sérusiaux et al. 2001; Sparrius 2002; Spier et al. 2002), none of them included B. colchica, despite some of the papers considering foliicolous taxa.