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.

Lichenization is a symbiotic ecological strategy that is widely distributed among the fungi, but in which the diversity of partners is relatively poorly known. Limited morphological diversity has hindered the recognition of true diversity in many lichen fungi, and also in their algal partners. In the temperate and boreal zones, the crustose microlichens are the most speciose but arguably the least studied, particularly in terms of their photobiont partners. In this study, we sampled eight species of Micarea s. str. collected from Europe, culturing and sequencing their green-algal partners using chloroplast (rbcL) and nuclear ribosomal (nucSSU) markers. All specimens collected in Great Britain were associated with members of Coccomyxa (including Pseudococcomyxa), but in the smaller sample of Ukrainian material, both Coccomyxa and Elliptochloris were found. This study extends the known range of fungal hosts for symbionts in the genus Coccomyxa, and supports earlier findings that a separate lineage of predominantly non-symbiotic Coccomyxa exists.

A number of possible displacing agents have been tested for their ability to release extracellular bound lead from Cladonia portentosa. Metal cations (Ni and Cu), thiol–rich reagents (glutathione, ammonium pyrrolidinedithiocarbamate) and some chelating agents (EGTA, EDTA at pH 9·5 or pH 2·7) were ineffective or caused membrane damage. Disodium EDTA at pH 4·5 was found to be an effective displacing agent, although the Na caused some release of intracellular K without membrane damage. This displacement procedure showed that no Pb suppliedin the laboratory entered the protoplast in 2 h. The effect of Ca, Cu, Pb, and Sr on membrane integrity was investigated.

In Norway three species are recognized in the genus Bryoria sect. Implexae, B. capillaris (Ach.) Brodo & D. Hawksw., B. implexa (Hoffm.) Brodo & D. Hawksw., and B. nadvornikiana (Gyeln.) Brodo & D. Hawksw. Notes on their morphology, chemistry, ecology and distribution are given. Bryoria friabilis Brodo & D. Hawksw., B. pseudofuscescens (Gyeln.) Brodo & D. Hawksw., and B. vrangiana (Gyeln.) Brodo & D. Hawksw. are considered to be conspecific with B. implexa. Bryoria setacea (Ach.) Brodo & D. Hawksw. is considered to be conspecific with B. capillaris.

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.

Morphological, anatomical, and chemical studies have been made of the types of about 90% of the world's reported Phyllopsora species, of types in related genera, and of much non-type material, including specimens collected in recent years by the authors and other botanists in East Africa. The findings are reported, and on their basis an attempt is made to delimit the genus. A detailed account is given, with key, of the East African species. The following 11 species are reported for East Africa, three of them being newly described: Phyllopsora albicans Mull. Arg., P. breviuscula (Nyl.) Mull. Arg., P. buettneri (Mull. Arg.) Zahlbr., P. chlorophaea (Mull. Arg.) Zahlbr., P. confusa sp. nov., P. haemophaea (Nyl.) Mull. Arg., P. martinii sp. nov., P. mediocris sp. nov., P. pannosa Mull. Arg., P. santensis (Tuck.) comb, nov., P. thaleriza (Stirton) G. Schneider. In addition one species is reported as undetermined (Species A). The following taxa are reduced to synonymy: Phyllopsora porphyromelaena (Vainio) Zahlbr. and P. formosana Zahlbr. with P. albicans; P. brachyspora Mull. Arg. with P. breviuscula; P. subparvifolia (Mull. Arg.) Mull. Arg. and Lecidea schizophylla (Vainio) Malme with P. chlorophaea; P. kiiensis (Vainio) G. Schneider and Lecidea schizophylla var. isidiata Malme with P. haemophaea; P. miradorensis (Vainio) G. Schneider with P. santensis; Psora ochroxantha f. aelhiopica (Stizenb.) Dodge with P. thaleriza; Lecidea ernstiana Mull. Arg. with P. ochroxantha (Nyl.) Zahlbr.; P. melanocarpa Mull. Arg. with Neophyllis pachyphylla (Mull. Arg.) G. Schneider; P. schizophylloides (Malme) G. Schneider with P. munda (Malme) Zahlbr.; and P. spinulosa (Vainio) Zahlbr. with P. polydactyla (Mull. Arg.) Zahlbr. The following new names and combinations are made: Bacidia laciniosa nom. nov., B. spruceana (Mull. Arg.) comb, nov., Phyllopsora bibula (Taylor) comb, nov., P. glabriuscula (Nyl.) comb, nov., P. janeirensis (Mull. Arg.) comb, nov., P. microphyllina (Tuck, ex Nyl.) comb, nov., P. pertexta (Nyl.) comb, nov., P. pyrrhomelaena (Tuck.) comb, nov., and P. santensis (Tuck.) comb. nov.

The genetic diversity within and among populations of Xanthoria parietina was studied at the subspecific level with a fingerprinting technique (RAPD-PCR) applied to sterile cultured multispore isolates, each being derived from a single apothecium. Populations from coastal, rural and urban sites from NW, SW and central France and from NE Switzerland were investigated. Between 1 and 8 microsites of a few decimetres square, each comprising 13 to 27 thalli of X. parietina, were analysed per population. A total of 132 isolates from epiphytic and 3 isolates from epilithic specimens were investigated. Phenotypic variation was recorded among some of the thalli in the field and among sterile cultured isolates in the laboratory. A high diversity of genotypes was observed, even among thalli growing side by side in phenotypically homogenous populations. An average of 73·5 % polymorphism was found in all samples. As shown with Principal Coordinates Analysis (PCO), most of the genetic variation (90%) resided within, not among, populations. As X. parietina had previously been shown with molecular and fingerprinting techniques to be homothallic, the potential genetic background of this diversity is discussed. Intense genotype rather than gene (allele) flow seems to be an important element in X. parietina populations.

Cladonia monomorpha is recognized as a distinct species in the Cladonia pyxidata group. It is characterized by thallus lobes with narrowly recurved margins, by the presence of discoid, bullate plates on the podetial surface and by long and sometimes branched proliferations of the scyphus margins supporting the apothecium discs. It is described from the Netherlands, where it occurs in acid inland sand dune areas with the highest terrestrial lichen diversity. It appears to be widespread in Europe on siliceous rock and acid sand.

Phylogenetic relationships among the hypothetical species pairs Lobaria kurokawae / L. retigera and L. pseudopulmonaria / L. isidiosa were investigated based on TLC techniques and the phylogenetic analysis of the internal transcribed spacers (ITS) nrDNA. Results of TLC demonstrate that L. retigera and L. kurokawae can be chemically distinguished from L. isidiosa and L. pseudopulmonaria by the absence of retigeranic acid. Parsimony analysis of 18 specimens shows two monophyletic clades – a L.retigera lineage and a L. isidiosa lineage—both including their apotheciate counterparts. Unlike the original hypothesis of species pairs, our study reveals transitions from isidiate morphs that have the potential to rarely form apothecia, towards apotheciate morphs that produce no vegetative propagules.

It has been suggested that the absence of anthraquinones is not a synapomorphic character, but appears independently in unrelated lineages of Teloschistaceae. We analyzed ITS nrDNA regions in species of the genus Caloplaca and present evidence for five such examples: the Caloplaca cerina group, C. obscurella, the C. servitiana group, the C. xerica group and the C. variabilis group (Pyrenodesmia). In some cases, loss of anthraquinones is observed only in individuals within ordinarily pigmented populations, but sometimes the loss covers whole lineages containing one or more species. Both situations are observed in the C. servitiana group. Loss of anthraquinones is always followed by the synthesis of ‘alternative’ pigments (often Sedifolia-grey). In the specimens with anthraquinone-containing apothecia studied, these pigments are not visible in apothecial sections after dissolving anthraquinones in K. Fully unpigmented apothecia have not been observed.

The Caloplaca xerica group is a newly established, infraspecific grouping of species related to, and similar to, C. xerica. The Caloplaca servitiana group is also newly established and represents an isolated lineage covering two rather different, but related species. Caloplaca neotaurica is described here as a new species with apothecia of two colour variants; orange-red (with anthraquinones) and grey (with Sedifolia-grey).

The genus Huea represents another taxon lacking anthraquinones within Teloschistaceae. The genera Apatoplaca and Cephalophysis, which lack anthraquinones, are tentatively placed in Teloschistaceae, but their phylogenetic identity has not been recognized. Hueidea is reported to have no anthraquinones, but its secondary metabolites should be studied further and its possible placement in Teloschistaceae assessed.

We suggest that Caloplaca abbreviata var. lecideoides and C. celata represent variants of C. stillicidiorum lacking anthraquinones.

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 species of the genus Fuscidea occurring in North America are revised. Two new species, Fuscidea appalachensis Fryday and F. texana Fryday, are described from eastern North America and southern Texas, respectively. Three new combinations are also made in Fuscidea: Lecidea aleutica Degel. is shown to be a distinct species and not a synonym of Fuscidea lowensis (H. Magn.) R. Anderson & Hertel as previously suggested and is here recognized as F. aleutica (Degel.) Fryday; non-sorediate, apotheciate specimens from eastern North America previously referred to F. recensa (Stirt.) Hertel, V. Wirth & Vězda are recognized as Fuscidea recensa var. arcuatula (Arnold) Fryday; and Fuscidea scrupulosa (Eckf.) Fryday is shown to be the correct name for Fuscidea subreagens (H. Magn.) Oberholl. & V. Wirth. Fuscidea subfilamentosa (Zahlbr.) Brako is shown to be a member of the Lecidea hypnorum group and the new combination Lecidea subfilamentosa (Zahlbr.) Fryday is made, and Lecidea gyrodes H. Magn., described from Tennessee, is shown to be a synonym of F. recensa var. arcuatula. Fuscidea cyathoides (Ach.) V. Wirth & Vězda, F. kochiana (Hepp) V. Wirth & Vězda and F. lightfootii (Sm.) Coppins & P. James are considered not to have been correctly reported from North America.

The relationship of Aspicilia uxoris within Megasporaceae is assessed within a phylogenetic context. ‘Aspicilia’ uxoris and other related species are recovered as sister to the genus Lobothallia s. str. and described here as a new genus. Teuvoa (Ascomycota, Megasporaceae) is erected based on nuclear ITS and LSU sequence data and morphological characters. In addition to Teuvoa uxoris, a second species, T. junipericola, is added to the new genus based on material collected from North America. Teuvoa junipericola, T. uxoris and T. tibetica form a group with 8-spored asci, absence of extrolites, rather short-sized conidia and ascospores, lack of a subhypothecial algal layer, and different substratum preferences (on organic substratum) with a sister relationship to genus Lobothallia s. lat. (Aspicilia subgenus Pachyothallia Clauzade & C. Roux). Based on spore measurements of the holotypes, Lecanora ferganensis Tomin from central Asia (Kyrgyzstan, Tajikistan and Uzbekistan), Lecanora atrodiscata Gintovt, from Tajikistan and Lecanora takyroides Dzhur. from Turkmenistan are new synonyms to T. uxoris. A lectotype for Lecanora ferganensis is designated, expanding the known distribution of T. uxoris from Algeria, Morocco and Spain, into Central Asia.

In our earlier work, we demonstrated that the oxidases tyrosinase and laccase occur widely in lichens from the Peltigerales. Recently, we discovered the occurrence of another oxidoreductase, a heme peroxidase, in the Peltigeralean ‘jelly lichens’ Leptogium and Collema. Here we present the results of a survey of peroxidase activity in a range of lichens. In addition to the jelly lichens, strong peroxidase activity also occurs within the Peltigeralean genera Lobaria, Pseudocyphellaria and Sticta. Significant activity occurs in the cell wall, and, unlike laccase activity, peroxidase activity increases considerably following the rehydration of dry thalli. However, activity is absent from Peltigera and from the non-Peltigeralean species tested here. Electrophoretic investigation showed that lichen peroxidases are oligomeric. Possible roles for peroxidases in lichen biology are discussed.

The new genus Degelia (Pannariaceae) is described to accommodate three primarily Southern Hemisphere taxa: D. gayana (Mont.) comb, nov., D. duplomarginata (P. James & Henssen) comb, nov., and D. durietzii sp. nov. A key to the species is given, with data on synonymy, morphology, anatomy, chemistry, habitat and distribution. Coccocarpia gayana var. melacarpina Nyl. is reduced to synonymy with Degelia gayana. Relationships of Degelia with genera in the Pannariaceae and Coccocarpiaceae are discussed. Degelia is distinguished from other genera in the Pannariaceae by periclinal arrangement of cells in the upper cortex, a lower cortex of 2–3 layers of thick-walled periclinal hyphae, and Scytonema as the phycobiont; and from genera in the Coccocarpiaceae by the structure and ontogeny of the apothecia. D. duplomarginata is known from New Zealand and Hawaii, D. durietzii from New Zealand and Tasmania and D. gayana from New Zealand, Tasmania, Australia, Chile and Tristan da Cunha.

The endemic African lichen Parmelia hottentotta (Ach.) Ach. and related species are placed in a new genus, Xanthomaculina Hale, on the basis of cortical chemistry and a combination of conidial and morphological characters, including umbilicate growth form, presence of cilia and a vaulted cortex.