Twenty-two species of Ramalina are reported from Brazil. Their taxonomy is discussed and a key is provided. Ramalina denticulata var. stephanophora is reduced to synonymy with R. aspera, R. flagellifera with R. camptospora, R. denticulata var. subolivacea and R. complanata f. reagens with R. complanata, R. dendriscoidella and R. tenella with R. dendroides, and R. bicolor with R. gracilis. Ramalina asahinae, R. calcarata, R. pusiola, R. sorediosa, and R. sprengelii are new to Brazil.

A taxonomic revision of 15 taxa of Diploschistes from India and Nepal is presented. Two species, D. awasthii and D. nepalensis, are described as new. Diploschistes caesioplumbeus (Nyl.,) Vainio, D. diacapsis (Ach.) Lumbsch and D. eugatieus (Massal.) Steiner are new records for the lichen flora of India.

Laurera robusta McCarthy & Kantvilas sp. nov. (Trypetheliaceae) is described from alpine heathland in Tasmania. Anthracothecium monosporum Müll. Arg. is synonymous with L. elatior (Stirton) D. Galloway, while L. megasperma var. tasmanica (Jatta) Zahlbr. is referable to Pyrenula.

A new species, Everniastrum diffractaicum the only member of the genus containing diffractaic acid, is described. It has much larger ascospores than those of any other member of the genus.

High performance thin layer chromatography (HPTLC) is a method that can be used for screening lichen substances. It is as simple to use as standard TLC, but has many advantages: It is more sensitive, it is possible to run more samples in a shorter period of time, and the amount of solvent used is much smaller. The material needed and the methods used are described in detail. Horizontal chromatogram development was used. Since two of the solvents used in system B have been substituted, and since the properties of the HPTLC plates are slightly different, our results are not entirely in accordance with the standardized TLC method. A revised table for the identification of 69 lichen substances (obtained from 62 taxa) is accordingly presented.

The decomposition of ground, dead (oven-dried) lichens has been studied in laboratory experiments that aimed to simulate decomposition in nature. Enzymes, common in soil animal guts and soil microbes, solubilized 29% of the lichen weight and 25% of lichen nitrogen. Approximately 9% of lichen nitrogen was mobilized to mineral forms during 97 days' incubation in soil or sand. Low moisture levels reduced the amount of nitrogen mobilized. In short-term (30 days) incubation studies, lichens at optimum moisture but low temperature lost 9% of their initial dry weight due to microbial metabolism. In contrast, lichens incubated for 30 and 135 days at similar moisture levels but higher temperatures lost 19% and 30% respectively of their initial dry weight due to microbial metabolism.

A laboratory experiment was conducted to determine the damage caused by snail grazing to 35 calcicolous lichen species and cyanobacteria from the Baltic island of Oland, Sweden. Individuals of four species of land snails (Balea perversa, Chondrina cliema, Clausilia bidentata and Helicigona lapicida) were allowed to graze on identified lichen species growing on pieces of limestone. Snail grazing on thalli and ascocarps was classified into four categories ranging from no damage to completely eaten. In general, some lichen species were heavily grazed, whereas others were only slightly damaged or not injured. Aspiciha calcarea, Tephromela atra and Verrucaria nigrescens were preferred by all snail species except Chondrina cliema. In general, lichen thalli that were not immersed in the calcareous rock and cyanobacteria were preferred, whereas ascocarps were avoided by one of the snail species (C. clienta). Immersed perithecia with a carbonized outer layer were avoided by all snail species except C. bidentata. Possibilities of chemical and mechanical defence properties in calcicolous lichens are discussed.