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.

Seasonal growth increments (%) were measured in the foliose epiphytic lichen Pseudocyphellaria berberina in north-western Patagonia. Growth was determined by measuring increase in weight (expressed as percentage of the original biomass) in transplanted thalli. Transplants were either hung freely from wooden frames or attached to tree trunks in a Nothofagus dombeyi forest and then weighed every three months between January 2001 and April 2003. The influence on growth increment of treatment, donor thallus, temperature, and absolute and relative humidity was analysed. Mean annual growth increment after two years, in both treatments was 12±1·07% (±SE). Growth increment was greatest in winter and lowest in summer; the mean winter growth increment was 6±0·50%, representing half of the annual growth, whereas most of the remaining growth occurred during both spring and autumn. Growth increments were similar for freely-hanging lichens and for the transplants attached to tree trunks. Individual trees had no consistent effect on growth while the donor thallus had a significant effect in the first season which then diminished, indicating acclimation in the transplants. Initial transplant weight had no influence on final cumulative growth, nor was there any consistent correlation between one season and another in the growth of transplants. Both transplantation methods proved to be useful for experiments on the growth of P. berberina.

As part of our ongoing studies of the Graphidaceae in North America, we resolve the status of all taxa traditionally assigned to the genus Graphina that have been reported from the continent north of Mexico. Treatments for the North American members of Acanthothecis, Carbacanthographis, and Diorygma are presented because several species of Graphina have been reassigned to these genera, and our studies of accumulated herbarium materials revealed the existence of several previously unreported and unrecognized species. The following new combinations are made: Acanthothecis leucopepla, A. mosquitensis, A. peplophora, and A. poitaeoides. Carbacanthographis muriformis is described as new to science based on material from Florida. The following taxa are reported from North America for the first time: Acanthothecis poitaeoides,Diorygma junghuhnii, D. reniforme.

The distribution patterns of lichens belonging to the family Peltulaceae and procaryotic algae (cyanobacteria) were studied in a rock pool on a sandstone koppie (‘Inselberg’). situated in the mopane savanna of the northern Transvaal. The co-dominant lichen species along the wall of the pool were: Peltula clavata (Krempelh.) Wetmore, P. euploca (Ach.) Poelt ex Pisut, P. obscurans (Nyl.) Gyelnik, and P. placodizans (Zahlbr.) Wetmore. The cyanobacteria Gloeocapsa sanguinea (Ag.) Kütz. emend. Jaag, Plectonema tomasinianum Gom. ex Gom., Rivularia sp., Scytonema sp. and Tolypothrix sp. grew epilithically between the lichen thalli. Unicellular species of the genus Chroococcidiopsis Geitler or Myxosarcina Printz occurred cryptoendolithically. The distribution patterns of several lichen species are presented and statistical tests reveal distinct correlations of the habitats of some species with light levels and water supply; e.g. the olive-green P. placodizans preferred the fully exposed situation near and along the rim of the rock pool; the black species P. clavata was restricted to areas next to the water level.

The Caloplaca holocarpa group contains members of the family Teloschistaceae with a strongly reduced thallus and conspicuous yellow, orange or red apothecia. In the absence of well-defined thallus characters, taxa of this group must be identified mainly by apothecial characters and are as a result often difficult to separate. The species of this group have been shown not to form a monophyletic entity, with representatives of other Teloschistaceae with more complex thalli intermixed among them. Caloplaca skii and C. syvashica are recognized here as two homogeneous clades with Caloplaca holocarpa-like phenotypes. Caloplaca skii, which is widespread in southern Europe, resembles C. cerinelloides but is distinguished by its smaller and narrower ascospores and by growing predominantly on xerophilous shrubs. Caloplaca syvashica is restricted to shrubs in salt marshes in the northern Black Sea region. It is similar to the British Caloplaca suaedae and Australian C. yarraensis, but differs from both, mainly in ascospore characters. Caloplaca yarraensis is closely related to the new C. syvashica but arguments against their conspecificity are emphasised. A key for epiphytic C. holocarpa-like Teloschistaceae from Europe is provided.

Detailed morphological and anatomical studies informed by molecular inferences with mtSSU as a marker revealed two new species of Micarea in Western Europe, both belonging to the core group of the genus, namely the M. prasina group: M. herbarum from the Netherlands and Poland and M. meridionalis from Portugal and Italy. Micarea herbarum looks like a small or depauperate M. denigrata but clearly differs by the lack of gyrophoric acid, while M. meridionalis is distinguished by its granular thallus and the production of micareic acid.

The Caloplaca crenulatella species complex is monophyletic, based on analysis of ITS nrDNA sequences. It is characterized mainly by its ascospores and a simplified thallus. Caloplaca aquensis, C. borysthenica, C. interfulgens, C. lactea, C. marmorata and C. tominii represent well-defined monophyletic lineages within it. Caloplaca diffusa, described here as a new species, is a well-supported lineage with a distinctive phenotype. Caloplaca crenulatella s. lat. and C. ferrarii s. lat. are heterogeneous taxa appearing in four and two places respectively within our tree. Caloplaca ochracea also belongs to the group, although it has different ascospore characters. Caloplaca gyalolechiaeformis and C. pseudocitrina are later synonyms of C. tominii. Arctic and North American sorediate specimens morphologically very close to C. tominii represent a separate lineage recently recognized as C. erichansenii. The North American Caloplaca nashii has a C. crenulatella-like phenotype but does not belong to the C. crenulatella complex. The identities of Caloplaca lacteoides and Caloplaca epigaea are not clear, but the latter may be a terricolous ecotype of one of the entities within C. crenulatella s. lat. A key to the European species of the group is provided.

This study focuses on dry acidophilous Scots pine forests, well known for their high biodiversity of cryptogams. We hypothesized that dense forests and heavy management were responsible for changes in species diversity, decreasing trends in lichen cover and increasing moss cover. This hypothesis was tested in three types of Scots pine forests maintained under three different management regimes: 1) managed forests (forest plantations regenerated by planting), 2) semi-natural forests (forest plantations regenerated naturally), both located in the Borská nížina lowland in SW Slovakia, and 3) natural forests (primordial vegetation without visible management actions from the association Cladonio-Pinetum Juraszek 1928), located in the Bory Tucholskie National Park, NW Poland.

We observed that the cover of the canopy tree layer had the most significant influence on the diversity of lichens. Managed forests are planted and maintained to achieve denser tree stocking, and although the environmental conditions created appear optimal for moss species, they are less suitable for terricolous lichens.

The importance of organic chemistry in the classification of lichens is well established, but inorganic chemistry has been largely overlooked. Six lichen species were studied over a period of 23 years that were growing in 11 protected areas of the northern Great Lakes ecoregion, which were not greatly influenced by anthropogenic particulates or gaseous air pollutants. The elemental data from these studies were aggregated in order to test the hypothesis that differences among species in tissue element concentrations were large enough to discriminate between taxa faithfully. Concentrations of 16 chemical elements that were found in tissue samples from Cladonia rangiferina, Evernia mesomorpha, Flavopunctelia flaventior, Hypogymnia physodes, Parmelia sulcata, and Punctelia rudecta were analyzed statistically using multivariate discriminant functions and CART analyses, as well as t-tests. Genera and species were clearly separated in element space, and elemental discriminant functions were able to classify 91–100 of the samples correctly into species. At the broadest level, a Zn concentration of 51 ppm in tissues of four of the lichen species effectively discriminated foliose from fruticose species. Similarly, a S concentration of 680 ppm discriminated C. rangiferina and E. mesomorpha, and a Ca concentration of 10 436 ppm discriminated H. physodes from P. sulcata. For the three parmelioid species, a Ca concentration >32 837 ppm discriminated Punctelia rudecta from the other two species, while a Zn concentration of 56 ppm discriminated Parmelia sulcata from F. flaventior. Foliose species also had higher concentrations than did fruticose species of all elements except Na. Elemental signatures for each of the six species were developed using standardized means. Twenty-four mechanisms explaining the differences among species are summarized. Finally, the relationships of four species based on element concentrations, using additive-trees clustering of a Euclidean-distance matrix, produced identical relationships as did analyses based on secondary product chemistry that used additive-trees clustering of a Jaccard similarity matrix. At least for these six species, element composition has taxonomic significance, and may be useful for discriminating other taxa.

The new lichenicolous Llimoniella phaeophysciae, known from Italy, Spain and the USA (Arizona) on Phaeophyscia, resembles Geltingia associata in the subcylindrical asci with uniseriate, shortly ellipsoid ascospores, but is distinguished by several important characters. Gelatinopsis acarosporicola, G. heppiae, Geltingia groenlandiae and Psorotichia terricola (syn. nov. Gelatinopsis leptogii) are considered to be congeneric with L. phaeophysciae, although some of them have elongate clavate and not subcylindrical asci and they are consequently combined in Llimoniella. These five species are distinguished from Llimoniella s.str. by a different excipular and epihymenial pigmentation not reacting with KOH and are treated as the informal L. phaeophysciae group. The new L. placopsidis is described from Placopsis in New Zealand. More complex pigmentation patterns are documented for L. pyrenulae and L. ramalinae. A revised key to the species of Llimoniella is presented. Gelatinopsis ericetorum and G. roccellae are combined in Rhymbocarpus. A redescription of Geltingia associata is given.

A revision is presented of the sorediate, lecanoric acid-containing Punctelia species occurring in Europe. Two species are common in western andcentral Europe, viz. Punctelia subrudecta s. str. and Punctelia ulophylla comb. nov.They differ in several morphological characters, most notably in the colour andpruinosity of the margin. Both species occur sympatrically, often together on onetree. A third species, Punctelia perreticulata, is known in Europe only from the Mediterranean.

The widespread and ubiquitous lichen-forming fungus Protoparmeliopsis muralis is able to form a thallus with Trebouxia species. In this study, several photobiont strains were isolated from different specimens of P. muralis and cultured in vitro. The compatibility of Trebouxia spp. and Asterochloris algae with P. muralis were investigated in in vitro resynthesis experiments and the re-lichenized bionts were observed with the scanning electron microscope. It was found that, in addition to compatible photobionts, also a presumably incompatible Asterochloris sp. was able to interact with the mycobiont. The life strategy that enables the mycobiont to form associations with a wider range of photobionts could be advantageous for the survival of the lichen and successful colonization of new habitats.

A phylogenetic analysis is presented, based on 57 morphological, anatomical, chemical and ecological characters, including 19 species from the genera Arthonia, Arthothelium and Syncesia. The aim of the study was to test the monophylyof some of the groups within the genus Arthonia suggested, for example, by Redinger (e.g. species with reddish ascomata, with grey-pruinose ascomata and with brown-black hypothecia). The results strongly support that Arthonia and Arthothelium are paraphyletic genera. The best-supported node contains all Arthonia species together with A. crozalsiana de Lesd., A. ruana A. Massal. (both hitherto placed in Arthothelium) and Syncesia myrticola (Fée) Tehler. A well-supported clade is formed by a group of pioneer species, often non-lichenized or poorly lichenized, including the type species of Arthonia, A. radiata. The species with reddish and/or K+ reddish ascomata form one clade and the species with more or less brownish or blackish hypothecia form another clade with Syncesia myrticola, the sister group to the Opegraphaceae and Roccellaceae. The results are discussed and compared with Redinger' grouping. Relationships to other genera within Arthoniaceae are briefly discussed. Arthothelium scandinavicumi Th. Fr., Arthonia dispersa (Schrad.) Nyl., A. punctiformis Ach. and A. mediella Nyl. are lectotypified.

The epiphytic lichen vegetation on the trunks of Pinus sylvestris and Picea abies was studied and analysed by canonical correspondence analysis in relation to a number of environmental variables. The distribution and abundance of epiphytic lichen species proved to be dependent on the age of the stand, showing divergent responses in relation to phorophyte species and environmental variables such as acidity of the bark and vertical location on the trunk. The importance of stand age in the pattern of community variation is concluded to be an outcome of interaction between changes in the structure of the tree canopy, microclimate and properties of the bark. The responses of single lichen species to changes in the environment seem to vary considerably, indicating differences in competitive ability and ecological strategy between the species.

SEM observations of the surface of branch tips of Bryoria fuscescens, before and after treatment to remove the matrix produced by the cortical hyphae, are described. Cortical hyphae are arranged in a simple, apical bundle, parallel to the long axis of the branch, which becomes, behind the apex, a hollow cylinder containing the algal population. The cortical structure is less complex than that of Usnea subfloridana. Substantial amounts of extracellular matrix are produced and the significance of this is discussed.

In order to evaluate the relative usefulness of the numerous bio-indication methods that use epiphytes as indicators for air pollution, a range of these different methods was applied within the same region (Flanders, Northern Belgium). The study area shows important air pollution gradients and little climatic differentiation. Ninety-one IAP indices were calculated with data collected in the immediate vicinity of SO⊂2 measuring stations on one randomly chosen tree, on ten neighbouring trees and in a sampling grid placed on the tree carrying the largest number of epiphytes. A large majority of indices showed a significant Spearman rank order correlation with mean SO⊂2 winter values over the 5 years 1990-94. Indices based on a selection of 17 lichens gave better results than those based on all lichens. The latter indices showed higher correlation than those using all epiphytes (including bryophytes). Indices using a quantitative estimate of cover or abundance or a combination of these did not result in a higher correlation. Sampling ten trees gave slightly higher correlation than the grid method or sampling of one tree. Taking into account supplementary evaluation criteria (time investment and degree of lichenological knowledge required), sampling of 17 bio-indicator species using a sampling grid is recommended within the study area. Monitoring the presence of all corticolous lichens within a sampling grid is recommended in general.