A phylogenetic study using large subunit ribosomal DNA sequence data of several species of Siphula, representing all phenotypically recognized species groups, suggests that Siphula is not monophyletic. One lineage, including the core group related to S. ceratites and the S. decumbens group, is placed with members of the Icmadophilaceae, whereas a second distinct lineage, comprising S. complanata, S. fragilis and their relatives, has evolved within the Coccotremataceae. To accommodate these species, the new genus Parasiphula is described as new to science. Parasiphula consists of species restricted to cool to cold latitudes of the Southern Hemisphere. The results show a remarkable case of parallel evolution of lineages that have lost sexual stages and propagate via thallus fragments.

This paper presents a study to partition the role of three regional-scale drivers – woodland extent and continuity, pollution regime, and climatic setting – in explaining the composition and richness of lichen epiphytes in Scotland. To do this we used partial canonical correspondence analysis and multiple least squares regression, to examine lichen communities across 170 study sites. First, our results demonstrate the importance of climate in explaining species composition. This highlights the relatively clean-air environment of Scotland within a European setting, and emphasizes the important consideration of regional context in the development of bioclimatic species-response models. This result contrasts with a previous similar study which collapsed complex environmental data into summary gradients, and which therefore discounted climate as a key factor. Second, we show a functional decoupling between composition and species richness, which was optimally explained by old-growth woodland extent and pollution, and only weakly explained by climate. The difference in explanatory variables between composition and richness is a focal issue in determining the processes by which species compositional change, driven by rapid and deep climate change, may indirectly impact species richness. For example, this impact may occur through an imbalance in rates of species extinction (for sensitive range-edge species) and establishment in a fragmented landscape (for dispersal-limited colonists), though operating against the ‘stabilizing effect’ of microclimatic setting.

Intrathalline phycobiont diversity was investigated in a rosette-forming lichen, Parmotrema pseudotinctorum, using a combination of Sanger sequencing, 454-pyrosequencing, conventional light and confocal microscopy, and transmission electron microscopy. A total of 39 thalli sampled in five Canary Island populations were investigated. Three novel lineages of lichen phycobionts were detected, all being inferred within the Trebouxia clade G. The most abundant phycobiont lineage, occurring in all lichen populations investigated, is described here as Trebouxia crespoana sp. nov. This species produces spherical to pyriform cells possessing a crenulate chloroplast with lobes elongated at their ends, and one corticola-type pyrenoid with very thin, unbranched tubules of curved profile. Trebouxia crespoana is clearly distinguished from all other Trebouxia species by a characteristic cap-like cell wall thickening produced on one side of vegetative cells, and the larger size of vegetative cells that reach 21(–26) µm in diameter.

The current view of the geographical ranges of lichens is often distorted by overly narrow or overly broad applications of names and by insufficient survey of most regions of the world. Here we present several cases where species of Teloschistaceae formerly thought to be limited to rather small territories in the western or eastern parts of Eurasia are in fact widespread in northern Eurasia. We support our findings with ITS nrDNA data in several new trees showing relationships in the genera Athallia, Calogaya, Caloplaca, Flavoplaca and Gyalolechia. The widespread species have little in common, except that most of them reproduce both sexually and asexually, and we discuss the possible influence of the combined reproduction on geographical range. Calogaya bryochrysion, Calogaya saxicola, Gyalolechia epiphyta and Gyalolechia ussuriensis are new combinations. Calogaya alaskensis is a younger synonym for C. bryochrysion. The generally arctic-alpine Calogaya bryochrysion also occurs on the bark of solitary trees in dry parts of the Altai Mountains. The Australian Flavoplaca cranfieldii is a younger synonym of F. flavocitrina. Gyalolechia epiphyta has been described numerous times, from different regions and substrata, as Caloplaca juniperi, C. laricina, C. tarani, Gyalolechia arizonica and G. juniperina. The name Gyalolechia xanthostigmoidea has recently been used for G. epiphyta, but it represents a distinct taxon. Gyalolechia ussuriensis is closely related to and morphologically indistinguishable from G. persimilis, but they have a different ecology and distribution and we regard them as distinct species. Caloplaca juniperina Tomin is lectotypified.

Two ubiquitous diazotrophic North American lichens, Peltigera aphthosa and P. polydaclyla, were subjected to simulated acid rain. Both lichens exhibited a 50% reduction in nitrogen fixation at pH 5, 80% reduction at pH 4 and complete inhibition at pH 2. Nitrogen fixation was zero after 20 days exposure to simulated rain at pH 3 and zero after fourdays at pH 2.

Lichenicolous fungi on species of the genera Baeomyces, Dibaeis, and Icrnadophila in Norway include Acarosporium lichenicola Ihien & Tonsberg sp. nov., Cercidospora parva Hafellner & Ihlen sp. nov., Phoma macuhformans Ihien sp. nov., Micarea inquinans (reported new to Scandinavia), Arthrorhaphzs vacillans, Pyrenzdzum actinellurn s. lat., Sphaerellotheciurn coniodes (all new to Norway), Arthrorhaphzs alpina, A. citrinella, A. grisea, A. rnuddii, Dactylospora athallina, D. attendenda, Epilichen glauconigellus, E. scabrosus, Stigmidium icmadophilae, Thelocarpon epibolum, and T. lichenicola. Their anatomy and morphology are described, and a key to the taxa provided. Host preferences are discussed, and distribution maps are provided for the obligately lichenicolous fungi and those that also occur autonomously.

To test the phylogenetic position of phenotypically peculiar species in the Physciaceae we generated 47 new sequences (26 of nrITS region and 21 of mtSSU rDNA) from 19 crustose taxa of Physciaceae mainly from the genus Rinodina. Phylogenetic analysis confirmed the Buellia and Physcia groups. The analysis revealed a considerable variability of characters traditionally used for classification, especially in the delimitation of the genera Buellia and Rinodina. While ascus types agree well with the distinction of the Buellia and Physcia groups, none of the other traditional characters, including excipulum type and ascospore thickening, were consistent within subclades of the Physcia group. We suggest that both excipulum type and ascospore characters are rather dynamic in the evolution of Rinodina species and only appear consistent in morphologically more complex foliose and fruticose groups, which are characterized by thallus characters not present in the crustose groups. Two recent taxonomic changes are supported by molecular characters: Endohyalina insularis (syn. ‘Rinodina’ insularis) and Rinodina lindingeri (syn. ‘Buellia’ lindingeri). In addition Rinodina parvula (syn. ‘Buellia’ parvula) is reinstated. New records for Endohyalina brandii, E. diederichii, E. insularis and Rinodina albana are presented.

Phycobiont cells of Parmelia laevigata contain chloroplasts with pyrenoids penetrated by a reticulum of tubules. The occurrence and significance of such tubules in algae is discussed. Although these tubules collapsed in desiccated cells, their lumen reappeared on rehydration. However, in such desiccated cells, pyrenoglobuli did not become peripherally located within the pyrenoid, except when damage occurred to the pyrenoid matrix. Rehydration of desiccated cells reduced the number of pyrenoglobuli per pyrenoid.

The reactivation of net photosynthesis and dark respiration from water vapour and from liquid water in the lichen Ramalina capitata var. protecta (H. Magn.) Nimis from sheltered habitats in Central Spain was investigated. CO2 gas-exchange response and thallus water content were measured in the laboratory as dry thalli were allowed to equilibrate by water vapour uptake under different relative humidities, and as saturated thalli dried. Water content of thalli from different habitats was also measured in the field during rainfall. The results show that the lichen is very efficient in using water vapour from the air for photosynthesis. Net photosynthetic rates were measured at very low water potentials (up to – 26-9 Megapascal) with water contents of the thalli below 30% dry weight. Maximum net photosynthetic rates measured after water vapour uptake were in some cases similar to those obtained after hydration by liquid water, while respiration rates were always lower after water vapour uptake, indicating a relatively larger activation of the photobiont. Moreover, photosynthetic rates at thallus water contents below 60% dry weight were higher when hydration was achieved through water vapour uptake than with liquid water. Field measurements had shown that this lichen reached water contents through water vapour absorption of 40% dry weight that would allow a positive balance of CO2 uptake. Possible ecological implications of differences in photosynthetic activation depending on the water source are discussed in terms of the carbon gain under natural conditions of this ombrophobous lichen.

Eugeniella palleola, Graphis paraschiffneri, and Malmidea cineracea are described from Nicaragua. Eugeniella palleola is characterized by having pale apothecial discs and prominent, white margins, and producing a complex chemistry including atranorin, stictic and norstictic acids, and an unknown substance. Graphis paraschiffneri has lirellae with a lateral thalline margin, striate labia, a completely carbonized excipulum, transversely septate ascospores, and contains norstictic acid in the thallus. Malmidea cineracea is characterized by a granulose-isidiate thallus with a yellowish medulla and a compact, crystal-encrusted excipulum. Malmidea nigromarginata and M. piperina are proposed as new combinations. Keys are presented to all known species of Eugeniella (9) and Malmidea (50).

Three species of Graphis (Graphidaceae) are described from Mexico from two research stations of the Universidad Nacional Autónoma de México (UNAM): Chamela Biological Station in the Cuixmala-Chamela Biosphere Reserve, Jalisco, and Los Tuxtlas Tropical Biological Station in the Los Tuxtlas Biosphere Reserve, Veracruz. The new species Graphis bungartzii Barcenas-Peña, Lücking, Herrera-Campos & R. Miranda is characterized by erumpent lirellae with a lateral thalline margin, striate labia and laterally carbonized exciple, transversely septate ascospores, and norstictic and connorstictic acids. Graphis chamelensis Barcenas-Peña & Lücking has prominent lirellae with a basal to lateral thalline margin, entire labia and completely carbonized exciple, transversely septate ascospores, and norstictic acid. Finally, Graphis rosae-emiliae Barcenas-Peña & Lücking is characterized by erumpent lirellae with lateral thalline margin, striate labia and completely carbonized exciple, transversely septate ascospores, and no substances detected by TLC. We present updates to the world key to Graphis for 41 newly described or reinstated species since the world key was published in 2009. The following new combination is proposed: Pallidogramme parvicarpum (B. O. Sharma & Khadilkar) Lücking comb. nov., based on Graphis parvicarpa B. O. Sharma & Khadilkar.

Two surveys of the lichen and bryophyte flora growing on oak twigs from a Welsh and a Danish locality were compared with additional data on bark pH and % nitrogen in thalli of Hypogymnia physodes. Despite differences in climate and lichen flora, both sites showed a shift in the lichen communities from nitrogen sensitive (nitrophobe) to nitrogen tolerant (nitrophile) species, which was correlated with both increasing bark pH and an increase in total nitrogen in thalli of H. physodes. The floristic survey from Wales was a repetition of a study eight years earlier (Wolseley & Pryor 1999) now showing a loss of nitrophobes in all sites and the appearance of nitrophiles in pasture sites in 2003. This study demonstrates that lichens on twigs can be used as an early warning system to detect a response to changes in land management and nitrogen deposition.

The campylidia hypothesis, first introduced by Müller Argoviensis (1881) and recently restored by Vězda (1983), for the erect helmet-shaped structures found on foliicolous lichens and usually known as ‘ Pyrenotrichum ’ is adopted as being the most satisfactory. In the Badimia pollilensis aggregate, campylidia are shown to derive from primordia identical to those of the apothecia. In the genus Sporopodium, algal cells are included in the conidiogenous layer and are dispersed together with conidia. This also seems to be the case in the genus Loflammia. Short descriptions are given for the most common campylidium known as ‘ Pyrenotrichum splitgerben ’ and for another not yet assignable to a peculiar genus. Loflammia denwulinii sp. nov. is described from New Guinea.

A preliminary annotated list of the foliicolous lichens and of their lichenicolous fungi occurring in the laurisilva in Madeira is presented. Fellhaneropsis Séerus. & Coppins gen. nov. is introduced to accommodate Bacidia myrtillicola Erichsen and Bacidia vezdae Coppins & James, both being present in Madeira on living leaves. Two new species are described: Byssoloma kalbii Sérus. sp. nov. and Fellhanera seroexspectata Sérus. sp. nov. The following combinations are introduced: Fellhanera lambinonii (Sérus.) Lücking & Sérus.,Fellhaneropsis myrtillicola (Erichsen) Sérus. & Coppins, F. vezdae (Coppins & James) Sérus. & Coppins, Woessia apiahica (Müll. Arg.) Sérus., W. canariensis (Lumbsch & Vězda) Sérus. and W. vasakii (Vězda) Sérus. A key to all foliicolous species of Fellhanera is presented. Bacidia buxi Vězda & Vivant and Bacidia gorgonea. Vězda & Poelt are reduced into synonymy with Fellhaneropsis myrtillicola, Tapellaria similes Kalb with Byssoloma marginatum(Arnold) Sérus., and Bacidia michaeliana Sérus. with .Bacidia lambinonii Sérus.

The following new species of pyrenocarpous lichens are described from Rondônia: Agonimia tenuiloba: corticolous, thallus with minute flabellate lobes developing goniocysts; ascomata smooth, grey, ellipsoidal; ascospores densely muriform, 30–50(–76)×20–35 µm. Anisomeridium lateriticum: saxicolous; conidiomata sessile, pyriform, ostiole with brown and hyaline septate setae; conidia simple to 1-septate, 8–11×2·0–2·5 µm. Anisomeridium triseptatum: corticolous, ascomata with lateral ostioles; ascospores (1–)3-septate, 25–30×7·5–10·0 µm, often with gelatinous appendages. Mycomicrothelia megaspora: ascospores ornamented, 1-septate, (27–)29–35(–40)×8–12 µm, often with a gelatinous layer 6–15 µm thick. Porina linearispora: corticolous; thallus green, shiny; ascomata immersed, 0·2–0·3 mm; ascospores filiform, (7–)9(–13)-septate, 75–90×1·5–2·0 µm. Porina maxispora: corticolous; thallus green, matt; ascomata immersed, 0·5–0·7 mm; ascospores filiform, (17–)23–35-septate, 95–110×4·5–5·5 µm. Porina novemseptatoides: saxicolous; thallus very thin, brown, glossy; ascomata superficial, 0·1–0·2 mm; ascospores fusiform, (7–)9-septate, 21–24×4·5–5·0 µm, with a c. 5 µm thick gelatinous layer. Porina termitophila: terricolous; thallus greyish green; ascomata emergent, 0·15–0·20 mm; ascospores fusiform, 1–3-septate, 13–15×2·5–3·0 µm. Pyrenula bispora: corticolous, thallus whitish, ascomata dispersed; hamathecium inspersed; ascospores 2 per ascus, muriform, 55–75×19–23 µm. Pyrenula leptaleoides: corticolous; thallus green to pale brown; ascomata deeply immersed in bark, with long necks fused in joint ostioles visible as brown dots on the surface; ascospores 23–27×8–11 µm, with rather angular lumina. Pyrenula rhomboidea: corticolous; thallus olive-brown; ascomata single, immersed; ascospores irregularly uniseriate, clavate-rhomboidal, 11–13×3·5–4·0 µm.

A key is provided to all species of pyrenocarpous lichens (except Trypetheliaceae) found in Rondônia. Nearly all species are new reports for Rondônia. Aspidothelium glabrum, Pyrenula leucotrypa and P. micheneri are newly reported for South America. The usually foliicolous Strigula nitidula is reported for the first time from bark.

The high lichen diversity is explained by the poor soils, supporting an only moderately dense forest where enough light can reach the tree trunks at ground level to support a rich flora of crustose lichens usually confined to the upper trunks.

Epiphytic lichens were sampled on selected trees in 19 sites radiating from Chiang Mai city including the adjacent mountain Doi Suthep in Northern Thailand using the VDI method (Verein Deutscher Ingenieure) to obtain frequency of occurrence in 10 area units per sampled tree. Sites selected included highly polluted sites in urban and adjacent industrial areas of Chiang Mai city, disturbed rural sites and undisturbed forest on Doi Suthep mountain, with altitudes varying from 260–1450 m. Lichen diversity was highest in upland sites and lowest in urban and agricultural sites. Analysis of lichen taxa at generic and at macrolichen species level and environmental data using PRIMER showed that upland and lowland sites were distinguished in the first division at both levels and correlated with altitude and vegetation type. Analysis of all taxa at generic level showed no separation of lowland sites but at macrolichen species level a better separation was obtained, suggesting that lichen diversity alone cannot be used for biomonitoring of air pollution. The relationship of epiphytic lichens to climate and pollution data available for Chiang Mai city and Doi Suthep is discussed and results compared with data from other studies in SE Asia.