Gene expression variation can be partitioned into different components (regulatory, genetic and acclimatory effects) but for lichen-forming fungi, the relative importance of each of these effects is unclear. Here, we studied gene expression in the lichen-forming fungus Lobaria pulmonaria in response to thermal stress and parasitism by the lichenicolous fungus Plectocarpon lichenum. Our experimental procedure was to acclimate lichen thalli to 4 °C over three weeks and then expose them to 15 °C and 25 °C for 2 hours each, sampling infected and visually asymptomatic thalli at each temperature. Quantitative Real-Time PCR was utilized to quantify gene expression of six candidate genes, normalizing expression values with two reference genes. We found that two genes encoding heat shock proteins (hsp88 and hsp98), two polyketide synthase genes (rPKS1, nrPKS3) and elongation factor 1-1-α (efa) were upregulated at higher temperatures. Moreover, we observed higher expression of hsp98 at 25 °C in samples infected by P. lichenum than in uninfected samples. Finally, in partial redundancy analyses, most of the explained variation in gene expression was related to temperature treatment; genetic variation and long-term acclimatization to sites contributed far less. Hence, regulatory effects (i.e. direct adjustments of gene expression in response to the temperature change) dominated over genetic and acclimatory effects in the gene expression variability of L. pulmonaria. This study suggests that L. pulmonaria could become a valuable lichen model for studying heat shock protein responses in vivo.

Herpothallon biacidum Frisch et al. is described from Queensland, tropical Australia. The new species is characterized by a thick byssoid thallus that is loosely attached to the substratum, globular to claviform to short cylindrical pseudoisidia, a brown to brownish black hypothallus, and by the presence of gyrophoric and norstictic acids. This is the first reported co-occurrence of gyrophoric and norstictic acids in the genus. The differences between H. biacidum and other species containing either norstictic acid or gyrophoric acid are discussed. Herpothallon biacidum is also compared with Cryptothecia eungellaeae. Both occur in north Queensland and have the same chemistry, but the latter has a closely adnate thallus and lacks the dark hypothallus and pseudoisidia. The circumscription of Herpothallon and its distinction from Cryptothecia are discussed.

Pertusaria yunnana G. L. Zhou & Lu L. Zhang from south-western China is described as new to science. This corticolous species is characterized by the white pruinose disciform apothecia, asci with 8 ascospores, and the presence of atranorin in addition to fumarprotocetraric acid. Related lichen taxa are discussed and a key to 21 corticolous species of Pertusaria with disciform apothecia and 8-spored asci is also provided.

Leptogium quercicola (Collemataceae), a new corticolous species, is described from central and south-eastern Spain. It is closely related to L. lichenoides, but differs in the development of dense fruticolous cushions, with lobes narrower than the smallest known forms of L. lichenoides. Moreover, spore length and width of the two taxa are significantly different. In addition, the two species differ ecologically; L. quercicola growing directly on bark of Quercus spp., while L. lichenoides colonizes rocks, soil and bark but always among mosses.

Pyrgillus tibellii, a new lichen species, is described from India. It is characterized by mazaediate, perithecioid ascomata, an excipular margin with an orange reddish pruinose rim reacting K+ reddish violet, and large, 3-septate ascospores.

Twelve species of Rhizocarpon coexist with 94 other species of saxicolous lichens at Jonas Rockslide, Jasper National Park, Alberta, Canada. The position of each Rhizocarpon species in the community is assessed with respect to environmental factors and biotic relationships. Each species shows distinct correlations with measured environmental factors and a different set of interactions with other species. Rhizocarpon bolanderi and R. superficiale stand out as opposites with regard to their biotic associations and environmental correlations. Competition between pairs of Rhizocarpon species is predicted to vary in intensity, as some species pairs never occupy the same microenvironment, whereas others frequently occur in similar locations. Using thallus diameter as a measure, there is evidence of high recruitment rates into populations of the sub-genus Phaeothallus and lower recruitment rates in the sub-genus Rhizocarpon.

One new species and six new records of the crustose lichenized genus Graphis are reported from Thailand. Graphis koratensis Pitakpong, Kraichak & Lücking sp. nov. is characterized by lirelline ascocarps with whitish grey or grey-green pruina along the slit, transversely septate ascospores, and the presence of norstictic acid. Phylogenetic analyses with two loci (mtSSU and nuLSU) show the distinct position of this new species within the genus. Six new records for Thailand are reported, including G. cincta (Pers.) Aptroot, G. jejuensis K. H. Moon et al., G. nigrocarpa Adaw. & Makhija, G. renschiana (Müll. Arg.) Stizenb., G. seminuda Müll. Arg., and G. subserpentina Nyl.

The new generic names Metamelanea Henssen and Strotnatella Henssen are described inthe Lichinaceae. They are denned by the developmental morphology of the ascocarp and thallus structure. In both genera the thallus is subfruticose, and the cyanobiont a single-celled member of the Chroococcales. The genus Metamelanea is based on the type species M.umbonata Henssen, newly described from the Alps, and M. melambola (Tuck.) Henssen comb, nov., found in North America. The genus Strotnatella is based on the single species, S. bermudana (Riddle) Henssen, formerly Psorotichia bermudana Riddle. The new genera are compared with species of other genera of the Lichinaceae: Gyrocollema, Lecidopyrenopsis and Porocyphus; some micrographs of Lecidopyrenopsis corticola Vainio. are also included. The new combination Porocyphus ocellatus(Th. Fr.) Henssen is made; Pyrenopsis triptococcus Nyl. is selected as lectotype of Pyrenopsis subgen. Cladopsis Nyl. (syn. Cladopsis (Nyl) Hue).

The Southern Hemisphere lichen genus Villophora in subfamily Teloschistoideae is analyzed based on DNA sequence data. Six species are described, five of which are new to science: V. darwiniana and V. wallaceana grow on lignum and bark in southern Patagonia and Tierra del Fuego; V. onas and V. patagonica are lichenicolous or saxicolous on rocks in southern Patagonia; V. rimicola is saxicolous in Antarctica. Based on a three-gene DNA analysis, Tayloriellina is shown to be closely related to Villophora, and Tayloriellina microphyllina is established as a new combination. A key is provided to all species of the two genera. Raesaeneniana maulensis is combined into Villophora.

Umbilicaria propagulifera (Vainio) Llano is reported as new to Poland. A morphological description is given and its distribution in both southern and northern hemispheres is established. U. vellea var. dendrophora is considered to be a synonym. The chemistry of U. propagulifera is variable. Its affinities within the genus and its possible relationship, as a species pair, with U. cylindrica are discussed.

Stirtonia byssoidea, S. coei and S. latispora, all from coastal hammocks within Everglades National Park, are described as new to science. Stirtonia byssoidea is characterized by a felty byssoid thallus, conspicuous immersed white pruinose-like lirelliform ascigerous zones, small ascospores and the presence of perlatolic acid. It is closest to S. alba but has a different thallus type and much smaller ascospores. Stirtonia coei is recognized by its lirellate ascigerous zones raised well above a greyish crystallate thallus, large ascospores and a lack of chemistry. It is closest to S. curvata but differs by its I+ blue thallus, strongly raised ascigerous zones and by having no lichen substances. Stirtonia latispora can be identified by its white lirelliform ascigerous areas immersed in a greyish green thallus, large, broad ascospores with a conspicuously enlarged mid cell and lack of substances. It would also key out close to S. curvata but differs by the aforementioned ascigerous zones, an I+ blue thallus, wider ascospores with a different locular configuration and its lack of chemistry. A key to the six species known from the Neotropics is also provided.

The original material of Sphinctrina tigillaris, collected in 1864, was relocated, re-examined, found to represent a species of Chaenothecopsis, and is transferred to that genus as C. tigillaris comb. nov. It occurred on a specimen of a polypore, now identified as Perenniporia meridionalis, on a beam in a Northamptonshire church, and does not appear to have been collected since. Perenniporia meridionalis is a predominantly central and southern European species which has not previously been recognized in the British Isles, although other English specimens have now been located in collections at Kew and referred to the related P. medulla-panis. The name Sphinctrina tigillaris had been overlooked since its original description in 1865, and is nomenclaturally distinct from Lichen tigillaris, the basionym of Cyphelium tigillare. Notes on five other calicioid fungi found on polypores, and a key to the six now known, are also included.

A world key is given to the species of Pyxine with lichexanthone in the upper cortex. Pyxine pustulata Aptroot & Jungbluth is described as a new corticolous species of Pyxine from São Paulo State in Brazil, with lichexanthone in the cortex, upper surface K−, a yellow to ochraceous medulla and clusters of laminal polysidiangia. Brazil is clearly the centre of Pyxine diversity, with 34 out of c. 70 species known worldwide.

The lichen flora of hazel woodland on the island of Eigg off the west coast of Scotland is described. One area is interpreted as representing ancient ‘climax’ woodland partly on account of its rich epiphytic lichen flora. At other sites various levels of exploitation have modified the lichen communities. Site comparison has enabled a number of species to be recognised which may be useful in the recognition of relict hazel woodland in other oceanic areas. The ecology of the indicator species is discussed. Pertusaria alpina Hepp ex Ahles is reported as new to the British Isles.

Eight corticolous species of Haematomma are recognized in Australia, including four new species (H. eremaeum, H. pruinosum, H. sorediatum and H. stevensiae spp. nov.) and one new combination (H. infuscum). The characters found useful in differentiation of the species included apothecium form, apothecial pigmentation, spore septation, and thallus chemistry. Taxonomic and distributional data are provided for all species. Two taxa are reduced to synonymy for the first time, and a key is provided.

Caloplaca erecta Arup & H. Mayrhofer is described here as new to science. It belongs to a group of dwarf-fruticose species, but cannot be accommodated within any of the known species of that group. It forms dense cushions of erect lobes on siliceous rocks, and is known only from Mt. Maungatua. This is the second dwarf-fruticose species of Caloplaca in the Australasian area, in addition to C. cribosa.