Samples of Hypogymnia physodes were transplanted to the environment of the former uranium mine at Žirovski vrh, Slovenia for two exposure experiments. The levels of the long-lived radionuclides, 238U, 226Ra and 210Pb in lichen material were measured after 4 and 7 months in the first experiment, and 4, 8 and 12 months in the second, and compared with the levels in lichens growing in-situ from the same sampling locations. They were also compared with the nuclide levels found in air particulates by gamma spectrometry obtained at the regular site monitoring stations. The results showed that each of the radionuclides had its own distribution pattern in this environment. The highest 226Ra levels were found in lichens in the near vicinity of the dry-tailings pile, while U concentrations were high in the valley of the confluence of the Todraščica and Brebovščica streams close to the former yellow-cake production plant in Todraž, and then decreased downstream. 210Pb was the most uniformly distributed radionuclide and exhibited the highest level. The results also confirm that active biomonitoring with transplanted lichens can be a useful and cheap supplement to instrumental air pollution monitoring.

Gloeoheppia is re-established as a separate taxon; the genus differs from Heppia in apothecial development and thallus structure. Gloeoheppia and the related genera Gudelia Henssen and Pseudopeltula Henssen described here are placed in the new family Gloeoheppiaceae in the Lichinales. In habit, the genera of Gloeoheppiaceae resemble species of Heppia and Peltula, whereas in apothecial development they correspond to some extent to the Lichinaceae. The species Gloeoheppia polyspora Henssen, Gloeoheppia rugosa Henssen, Pseudopeltula dicyanophora Henssen, Pseudopeltula heppioides Henssen, Pseudopeltula myriocarpa Henssen and Gudelia mexicana Henssen, are described for the first time. In Gloeoheppiaceae the thalli are ecorticate and the hyphae reticulately branched. The prototunicate asci contain eight, or up to 16, colourless and simple, occasionally two-celled spores. In species of Pseudopeltula, the apothecia are of a complex structure. The cyanobionts are small and single-celled; in P. dicyanophora ‘ internal cephalodia ’ with an additional, filamentous cyanobiont are formed. Lectotypes are designated for Endocarpon turgidum Ach. and Heppia furva Hue in Patouill.

Growth of the mycobiont of Ramalina siliquosa and the secondary metabolites subsequently produced under various osmotic culture conditions were examined. The secondary metabolite content and the growth rate changed greatly when different quantities of sucrose were added to the culture medium. Salazinic acid was found only in mycobionts cultured on a medium with 10 or 20% sucrose, the mycobiont growth rate being higher than on conventional medium. Similarly, in Lobaria discolor, gyrophoric acid was found only in mycobionts cultured on a medium with 10% sucrose.

Ten species and one variety of Verrucaria Schrader are known from creeks and rivers in eastern Australia. Verrucaria austroalpina sp. nov., V. inconstans sp. nov., V. mundula sp. nov., V. mundula var. deminuta var. nov., V. phaeoderma sp. nov., V. tasmanica sp. nov. and V. tholocarpa sp. nov. are described. The combination V. puncticulata (P. M. McCarthy) P. M. McCarthy is made for V. hydrela var. puncticulata P. M. McCarthy. Verrucaria margacea (Wahlenb.)Wahlenb. and V. praetermissa (Trevisan) Anzi are reported from the Southern Hemisphere for the first time.

The lichen flora and habitats in the Syowa region of continental Antarctica were surveyed. The distribution patterns of lichens appear to reflect habitat salinity, derived from wind-blown sea spray. Some halotolerant species are established in saline habitats where snow dunes are well developed. Snow and ice ameliorate the salinity of the habitat and provide a major source of moisture for lichens. Wind-borne drift snow carried by katabatic winds or occasional snow showers also provide the source of moisture to lichens growing on dry rock habitats in the Syowa region.

Lobaria pulmonaria and other members of the Lobarion were found to inhabit drainage channels below old and large wounds on the trunks of various deciduous trees in stands of long ecological continuity in a forest reserve dominated by Picea abies in southeastern Norway. Such channels were richer in minerals and had a higher pH than normal bark, which was covered with more acidophytic epiphytic communities, mainly the Pseudevernion. Chemical microhabitat differentiation was most clear in edaphically poor sites. The restriction of a previously ubiquitous Lobarion to mineral-rich microsites on stems is probably an effect of acid rain. Since acidification seems to make the Lobarion more dependent upon old and damaged stems, modern forestry probably aggravates the damage caused by acid rain.

A simple DNA extraction method is described, applicable to many different kinds of lichens. The method involves the use of the detergents DTAB and CTAB and yields DNA that can be directly amplified with the polymerase chain reaction or digested with restriction enzymes

The taxonomy of the foliicolous members of Arthoniaceae (Anhonia, Arthothelium, Cryptothecia, Eremothecella) in Costa Rica is revised. Cryptothecia farkasiae sp. nov. is described, being closely related to Stirtonia sprucei, and bearing pycnidia reminiscent of Eremothecella. Anhonia lividofusca is placed in synonymy with A. aciniformis. Pycnidia and pycnospores are further described for Anhonialeptosperma, A. cyanea, A. palmulacea, A. trilocularis, Anhothelium cingulatum, Stinonia sprucei and S. macrocephala, and campylidia were found on thalli of Anhonia aciniformis. Anhonia nigratula and Cryptothecia Candida are reported for the first time from Costa Rica, and new localities are given for previously reported species. Ecological data are provided, and the relationships between foliicolous members of the Arthoniaceae are discussed.

The health, abundance, metal content and species richness of corticolous macrolichens and bryophytes of Quercus ilex were compared at nine roadside stations in Montseny Biosphere Reserve, 40 km NNE of Barcelona, and at a control site outside the industrial metropolis. Stations were characterized by traffic levels and the correlated parameter airborne particles. Corticolous flora at all stations was dominated by sorediate Parmelia species (P. caperata, P. soredians, P. subrudecta, P. subaurifera, P. sulcata and P. perlata). Damage, mainly due to arthropod feeding and fungal parasites, ranged from 14 to 33% of mean cover per station in the park and was 10% at the control site. Elevated levels of Pb, Zn and Cu were found in large thalli near the roadsides.

The standing crop of the epilithic foliose lichen Mastodia tesselata and some other species, the nutrient status (chloride, phosphate, nitrate and ammonium) of the substratum, slope and moisture availability were studied in 29 sample plots on Petermann Island (65°10'S, 66°30'W), Antarctica. The observed standing crop values for Mastodia ranged from 49 to 614 g m 2, with an average of 310 g m 2 (17 sample plots), and were 542 g m−2 for Rinodina petermannii (one sample plot) and 314 g m−2 for the alga Prasiola crispa in two meltwater pools. A regression equation with log-transformed ammonium and phosphate concentrations as predictors explained 75% of the observed variance in Mastodia standing crop. No significant influence of chloride or nitrate concentration on the Mastodia standing crop was detected, indicating that Mastodia is a salt-tolerant lichen species, but is not an obligate halophyte. The maximal standing crop of Mastodia on Petermann Island proved to be lower than maximal values found for fruticose macrolichen vegetation in maritime and continental Antarctic. The Mastodia standing crop on Petermann Island was similar to the standing crop of this species on subantarctic Marion Island.

The influence of acute gamma radiation on four physiological characteristics of lichens was investigated. Membrane permeability in irradiated thalli of Cladonia arbuscula, Cetraria islandica and Hypogymnia physodes increased considerably compared to controls. The nitrogen content in Peltigera aphthosa appeared to be stable to acute gamma radiation. Up to 1000 Gy there was no essential decrease in respiration intensity in H. physodes and P. aphthosa or of peroxidase activity in P. aphthosa..

Extensive material of Caloplacafrom Arctic and Antarctic regions has been critically examined. A list of 49 species is presented for Arctic regions. They are presumed to have a more or less circumpolar distribution. Twenty-two species are listed from the Antarctic region, but about ten more, probably undescribed species, are present there. About one-third of the species in the Antarctic region are bipolar or widespread in cold regions; these include mainly terricolous and muscicolous species and none of them are maritime. It is assumed that migration of the bipolar or cosmopolitan species has taken place along the Andean mountain chain, whereas the maritime polar species have evolved separately in the two hemispheres. The Caloplaca species of the Antarctic region are provisionally assigned to the following distribution types: continental Antarctic, western Antarctic, insul-Antarctic and sub-Antarctic. Caloplaca exsecuta, C. saxicola and C. phaeocarpella are recorded as new to the Antarctic region. Caloplaca johnstonii (Dodge) Søchting & Olech, comb, nov., is established as the correct name of C. tenuis Øvstedal.

Thalli of Ramalina capitata were sprayed with deionized water, 10 mM solutions of KNO3 or NH4Cl, or maintained without any water supply, for 10 days under controlled conditions. The lichens without a water supply showed an increase n antheraxanthin, lutein and β-carotene. The samples treated with deionized water showed a significant increase in violaxathin, antheraxanthin and β-carotene. The lack of a significant difference in zeaxanthin could indicate the absence of de-epoxidation of violaxanthin to zeaxanthin via antheraxanthin. Those samples treated with nitrate solution showed a significant increase in all pigments except for antheraxanthin. In contrast, ammonium treatment did not induce changes compared to water alone, except that antheraxanthin decreased. The lichens treated with nitrate exhibited a significant increase in both chlorophyll a and chlorophyll b, but ammonium affected only chlorophyll b.

Three long-term studies of lichen growth and colonization have been undertaken at Signy Island, South Orkney Islands, in the maritime Antarctic. Small individual thalli of several crustose species and uncolonized plots on 12 fresh rock surfaces were photographically monitored at intervals of 3–4 years over a period of up to 20 years. The development of Ochrolechia frigida colonies on a regenerating moss bank, recently uncovered by a receding glacier, was similarly monitored. The results indicate that many lichens growing in sites enriched by nitrogenous compounds derived from populations of sea birds, have relatively rapid colonization and growth rates. Mean percentage increase in thallus area can be as high as 15–32% per annum in some nitrophilous saxicolous species (e.g. Acarospora macrocyclos, Xanthoria elegans and species of Buellia and Caloplaca), but as low as, 0·4–4% in nitrophobous species (Lecanora physciella, Lecidea sp., Rhizocarpon geographicum). Umbilicaria antarctica and Usnea Antarctica also yielded data indicating high growth rates, with colonist plants reaching several centimetres after 20 years. Colonization by mixed assemblages of lichens of new rock surfaces can attain 40->90% cover after 20 years in nutrient-enriched sites, and even 20–25% in non-biotically influenced sites. Colonization by or increase in extant O. frigida on the regenerating moribund moss bank was also quite rapid. It is suggested that the exceptionally large thalli of several lichen species and the locally extensive dense lichen fellfield communities in the maritime Antarctic may be much younger than previously supposed.