The generic name Paralethariicola gen. nov. is introduced for a lichenicolous fungus very similar to Lethariicola, but differing by the presence of excipular hairs, asci with a hemiamyloid apical ring and a more flattened apex, curved or slightly helicoid ascospores with ± pointed ends, and thicker paraphyses. The single species, Paralethariicola aspiciliae sp. nov., is lichenicolous on Aspicilia, and is known from continental Spain and Sardinia.

The new species Thyrea porphyrella Schultz, Büdel & Porembski, in the Lichinaceae, is described from tropical South America. It grows on granite inselbergs in SE Brazil and in southern Guyana. Diagnostic characters are the very thin, superficially smooth but conspicuously uneven to folded thallus lobes of reddish-brown to crimson colour.

ITSl and ITS2 regions were sequenced from a number of Parmeliopsis ambigua and P. hyperopta specimens from Uppland, Sweden. The data were analysed cladistically and the ITS region was found to contain enough variation to support the hypothesis that the taxa should be regarded as species rather than chemotypes.

Three species of the Buellia epigaea-group, Buellia dijiana Trinkaus, Buellia georgei Trinkaus, Mayrhofer & Elix, and Buellia lobata Trinkaus & Elix, are described as new from Australia. The taxonomy, morphology, anatomy, chemistry, biogeography, and ecology of the three taxa are discussed. Characters which distinguish these species from the corresponding taxa in the northern hemisphere include secondary compounds (presence of xanthones) and filiform conidia. An extended key is provided for the whole Buellia epigaea group as well as other terricolous species of the genus.

Three new species, Chaenothecopsis eugenia, Chaenothecopsis vinosa and Chaenothecopsis weiana are described from the Gongga Mountains in China. Chaenothecopsis pibsa is reported as new to Eurasia, and Chaenotheca sphaerocephala as new to Asia. Three genera, Cyphelium, Pyrgidium and Stenocybe, and 13 species are reported as new to China. Descriptions and illustrations of the new species are presented along with data on their habitat ecology and distribution.

The Azorean lichen previously and erroneously referred in the literature to Erioderma wnghtii, belongs to the complex, widespread species E. leylandii, and is escribed as subsp. azoricum, possibly representing a relic, ancestral form with a composite chemistry. It is presently only known from Pico where it is under threat owing to the destruction of the forests.

The lichen flora associated with twenty saline lagoons in England is described. Though often scarce, lichens were present on shingle, miscellaneous stones, half-submerged concrete structures, retaining walls, salt marsh vegetation, wooden posts, and strand-line materials. Sites that had been modified by the activity of man often held richer assemblages than ones in a more natural condition. The lichen flora is a mixture of common-place species and maritime specialists. The large lagoon behind Chesil Beach, known as ‘The Fleet’, was the most important site surveyed. Many of the marine lichens present are typical of very sheltered coastlines. Caloplaca suaedae, found at two sites, is described as new to science.

Epiphytic lichens (and some non-lichenizedfungi) on 34 coppices (204 stems) of Corylus avellana were investigated in a 140 ha study area in south-western Norway. A total of 65 species were recorded on a total bark area of 63 m⊃2. Corylus in broad-leaved deciduous forest supported more species of macrolichens, and fewer species of microlichens, than Corylus in pine forest. The macrolichen flora of the deciduous forest differed from that of the pine forest by having a rich flora of species belonging to the Lobarion alliance. Old Corylus coppices with tall stems (>8 m), large girth (>8cm diameter at breast height) and a noticeable cover of macrolichens (>10% of bark area) supported the highest number of rare species, and overall, species of macrolichens. More than 50% cover of microlichens indicated richness and rarity of microlichens on Corylus. 11 2001 The British Lichen Society

A phylogenetic hypothesis based on nuclear ITS sequence data is presented for the family Physciaceae based on various representatives of foliose and fruticose groups and a number of species selected from the crustose genera Rinodina and Buellia s.l. The analysis supports the monophyly of the Physcia- and the Buellia- groups. This is in agreement with existing morphological evidence, particularly ascus characters. The Physcia group in the analysis includes the genera Anaptychia, Heterodermia, Hyperphyscia, Mobergia, Phaeophyscia, Phaeorrhiza, Physcia, Physconia, Rinodina, and Rinodinella, while the Buellia group includes Amandinea, Buellia and Diploicia. The genera Physcia, Phaeophyscia, Phaeorrhiza and Rinodinella were well supported as monophyletic groups. The support for Physconia is low. Rinodina and Buellia are not supported as monophyletic genera. In agreement with ascus and ascospore characters, Buellia lindingeri is placed within the Rinodina group, close R. lecanorina. The genus Amandinea as currently circumscribed was not supported as a monophyletic group. The analysis confirms results from other lichen families that foliose members have evolved more than once from crustose lichens. Rinodina and Rinodinella species without chemical compounds in their thalli form the sister group to Phaeophyscia, and both groups form a monophyletic assemblage. A more detailed analysis of the Physcia group is presented. Whilst several of the foliose genera were well supported, there is only poor support for traditionally accepted crustose genera. The taxonomic implications of these findings are discussed.

Two new species belonging to the lichen families Pilocarpaceae and Ectolechiaceae are described from tropical Africa: Calopadia lucida sp. nov. (Ectolechiaceae) from Tanzania, being similar to C. puiggarii but differing in the UV fluorescent thallus and the pruinose apothecia, and Fellhanera ivoriensis sp. nov. (Pilocarpaceae) from the Ivory Coast, differing from the related F.rhapidophylli by the sorediate thallus and from other sorediate taxa by the combination of pale soralia, dark brown apothecia, and the ellipsoid-bacillar conidia. A key to the nine sorediate species of Fellhanera is provided.

Lichen communities were examined on 62 churches in Mecklenburg–Vorpommern, Germany. Ninety-six lichen species and subspecies, and three species of lichenicolous fungi identified. Tylothallia biformigera and Lecanora campestris subsp. dolomitica are reported as new Germany, and another 20 species are considered as threatened. This implies that the stone walls churches represent an extremely important habitat in Mecklenburg–Vorpommern, where natural outcrops are rare. The distribution of lichen species was analyzed quantitatively in relation to several habitat factors. Aspect, substratum and inclination were found to be important factors for 35, 34 31 species, respectively. The height of the relevé was a significant factor for many species. Twenty-three species, which are described in the literature with oceanic to suboceanic distributions, occur significantly more frequently near the coast. The ways in which microclimate affects each these habitat factors and contributes to the presence or absence of a species or group of species discussed. Some species have narrow and specific habitat demands, whereas others thrive under wide range of environmental conditions. The advantages of a strictly schematic approach with detailed statistical analysis are discussed.

Micarea neostipitata sp. nov. is described from conifer trunks in conifer woodlands and bogs in eastern U.S.A. It is superficially similar to M.stipitata, but differs from that and other related species in having minute crystalline inspersions in the hymenium and pycnidial wall, which apparently belong to lobaric acid, shorter conidia, and in possessing fumarprotocetraric acid in the thallus.

The Coccotremataceae is a small family including two genera: Coccotrema with a crustose, granulate to verrucose thallus and Lepolichen with terete lobes and rhizines. The generic concept based on this morphological difference was re-evaluated using three molecular markers, mt SSU rDNA, nu LSU rDNA, and the nu ITS region. The analysis of the ITS region does not provide sufficient resolution within the Coccotremataceae, while the other two data sets contradict the current generic concept. The mt SSU and nu LSU data sets and the combined analysis of the two data sets all place Lepolichen within Coccotrema. However, an alternative topology with monophyletic Coccotrema cannot be rejected when the ITS data set is included in the combined analyses. This shortcoming of the ITS data set can be overcome by the combined analysis of all three data sets, where monophyletic Coccotrema can be rejected using parametric bootstrapping, as in the mt SSU and nu LSU data sets and combination thereof. It is proposed to reduce Lepolichen into synonymy with Coccotrema. The correct name for the only species previously placed in Lepolichen is Coccotrema coccophontm (Mont.) I. Schmitt, Messuti & Lumbsch.

Menegazzia wandae Bjerke from Chile is newly described. It is characterized by lacerate soraliathat are formed on laminar pustules; the sinuous, rather imbricate lobes with brown-black margins, and the presence of thamnolic acid in the medulla. Apothecia are unknown, and pycnidia are rare. The species is known from Chile between latitudes 38°30´S and 46°40´S.

The identity of photobionts from 20 species of the Physciaceae from different habitats and geographical regions has been determined by ITS rDNA sequence comparisons in order to estimate the diversity of photobionts within that lichen group, to detect patterns of specificity of mycobionts towards their photobionts and as a part of an ongoing study to investigate possible parallel cladogenesis of both symbionts. Algal-specific PCR primers have been used to determine the ITS rDNA sequences from DNA extractions of dried lichens that were up to 5 years old. Direct comparisons and phylogenetic analyses allowed the assignment of Physciaceae photobionts to four distinct clades in the photobiont ITS rDNA phylogeny. The results indicate a diversity within the genus Trebouxia Puymaly and Physciaceae photobionts that is higher than expected on the basis morphology alone. Physciaceae photobionts belonged to 12 different ITS lineages of which nine could unambiguously be assigned to six morphospecies of Trebouxia. The identity of the remaining three sequences was not clarified; they may represent new species. Specificity at the generic level was low as a whole range of photobiont species were found within a genus of Physciaceae and different ranges were detected. The photobionts of Physcia (Schreb.) Michaux were closely related and represented one morphospecies of Trebouxia, whereas the algal partners of Buellia De Not and Rinodina (Ach.) Gray were in distant lineages of the ITS phylogeny and from several Trebouxia morphospecies. Photobiont variation within a genus of Physciaceae may be due to phylogeny, geographical distance or because photobionts from neighbouring lichens were taken (“algal sharing“). At the species level Physciaceae mycobionts seem to be rather selective and contained photobionts that were very closely related within one morphospecies of Trebouxia.

The lichen composition on wayside Quercus robur in the Netherlands was related tobark properties (pH, EC, NH4+, SO42-, NO3-)and levels of air pollution (SO2 and NH3). The pH of the bark and the susceptibility to toxic substances appear to be the two major primary factorsaffecting epiphytic lichen composition. These factors have independent effects on the lichen composition.Most of the so-called nitrophytic species appear to have a low sensitivity to toxiceffects of SO2; their only requirement being a high bark pH. An increased bark pH appears to be the primary cause of the enormous increase in nitrophytic species and the disappearance of acidophytic species over the last decade in the Netherlands. Measurements of ambient NH3 concentrations in air show that there is a nearly linear relationship between the NH3concentration andthe abundance of nitrophytes on Quercus. The abundance of nitrophytes was not correlated with SO2 concentrations. Most of the acidophytic species appear very sensitive to NH3 since in areas with concentrations of 35 µg m-3 or more, all acidophytic species have disappeared. Current methods using species diversity to estimate or monitor SO2 air pollution need some modification, otherwise the air quality may be erroneously considered to be relatively good in areas with high NH3 levels.

A new method has been developed to measure chlorophyll a fluorescence of bryophytes and lichens in situ in the field. Specially designed aluminium stands fixed to rocks or other suitable substrata allow several cryptogam thalli to be measured sequentially with only one pulse amplitude modulated (PAM) chlorophyll a fluorescence analyser. The stands guarantee a fixed position for the fluorescence probe in relation to the thallus surface and also provide the possibility to darken the thalli so that both the apparent and the potential quantumefficiency of PSII (▵F/Fm′ and Fv/Fm) can be measured. A detailed analysis of chlorophyll a quenching parameters (qP, qN, NPQ) can also be performed with only minimal changes in the environmental conditions. The method allows easy detection of periods of metabolic activity and inactivity of the poikilohydric organisms. In combination with gas–exchange and microclimatic measurements the carbon balance also can be calculated. The method is described in detail and examples of its application in the field are presented

The new genus Coniarthonia is described to accommodate a group of species previously placed in Anhonia and Arthotheliwn. Crystallized red pigments that are distributed throughout hydrophobic ascomatal structures are characteristic of the new genus, which includes species with both muriform and transversely septate ascospores. Coniarthonia erythrocarpa, C. gregarina, C. pulchernma, C. pyrrhula and C. ivilmsiana are new combinations, and C. haematodea is new to science. Two subgroups are distinguished in the genus: the C. pyrrhula group, with larger ascospores, and the C. pulckcrruna group, which has comparatively small, one-septate ascospores. The reddish compounds are characterized by TLC. A key to the species is provided.

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.