Lithographa serpentina Coppins & Fryday is newly described from Campbell Island (New Zealand), and is unique within its genus and order for having submuriform ascospores. Also newly described are Lithographa opegraphoides Coppins & Fryday from the Falkland Isles, Rimularia actinostoma Coppins & Fryday from Canada (British Columbia), and Rimularia austrolimborina Coppins & Fryday from southern Chile. The new combination Lithographa graphidioides (Cromb.) Imshaug ex Coppins & Fryday is made to accommodate the previously misunderstood Stigmatidium graphidioides Cromb. and the more recently described Lithographa subantarctica Hertel & Rambold. A key to all described species of Lithographa is provided.

The new species, Polysporina frigida Kantvilas & Seppelt is described and illustrated. It is the first record of this genus from the Antarctic continent.

The new genus and species Nyungwea pallida is characterized by a thin thallus lichenized with Trentepohlia and pale stipes producing goniocysts. Its taxonomic position is uncertain. It is named after the large pristine montane forest of Nyungwe in Rwanda (East Africa) where it was first found; it is also known from the Mabira forest in Uganda.

The new species Arthothelium desertorum is described from the Namib desert. It is characterized by its saxicolous habit and areolate thallus containing divaricatic acid.

A new species, Chrysothrix septemseptata, is described from India. It is characterized by 7-septate ascospores, which is unique within the genus. It is currently known only from the Sundarbans Biosphere Reserve, where it grows in mangrove plantations.

Thirty-one taxa of Gyalideopsis and its recent segregates (Ferraroa, Jamesiella, Lithogyalideopsis) are reported in a first assessment of the group from Costa Rica. Six species are described as new, all originating from perhumid montane rainforest: Gyalideopsis altamirensis Lücking & Umaña, with broadly sessile, brown apothecia and single-spored asci with muriform ascospores (hyphophores unknown); G. macarthurii Lücking, Umaña & Aptroot, with dark greyish brown apothecia having their margin covered by triangular thalline lobules and shortly bristle-shaped hyphophores producing moniliform diahyphae; G. pseudoactinoplaca Lücking & Chaves, with sessile, globose diahyphal bunches similar to those of Actinoplaca and resembling isidia (apothecia unknown), G. wesselsii Lücking, Sipman & Chaves, with verrucose thallus, dark greyish brown, applanate apothecia with single-spored asci producing muriform ascospores, and minutely spathulate, dark brown hyphophores with moniliform diahyphae, and Jamesiella chaverriae Chaves, Umaña & Lücking, with isidioid hyphophores (‘thlasidia’) which are flask-shaped and apically thinly ciliate (apothecia unknown). A further species, Gyalideopsis sp., with distinctly stipitate, umbelliform hyphophores, is not formally described due to the lack of apothecia and hyphophores. A further nine species are reported as new to Costa Rica: G. buckei, G. capitata, G. confluens, G. giganteoides, G. megalospora, G. napoensis, G. nepalensis, G. palmata, and Lithogyalideopsis zeylandica. A world-wide key to all presently known 94 taxa of Gyalideopsis and its recent segregates is presented, as well as a checklist.

Lichens were recorded on Quercus petraea trunks and twigs near ammonia recording stations in ‘continental’ Norfolk, and ‘oceanic’ Devon in order to test indicator values developed for epiphytic lichens in areas of high atmospheric ammonia in the Netherlands. Lichens on trunks in Norfolk showed a similar correlation of nitrophyte indices with ammonia concentration and bark pH as those in Holland, whereas in Devon there was no correlation with nitrophyte indices on trunks and a negative correlation with acidophyte indices. Results on twigs in both sites suggest that lichens on twigs respond more rapidly to recent changes in ammonia concentrations while trunks may maintain relict lichen communities due to either a legacy of previous acidification or ecological continuity. The results suggest that loss of acidophytes is taking place prior to the establishment of nitrophytes indicating the importance of establishing levels of ammonia at which sensitive communities are at risk.

A field experiment was established to examine the effect of nutrient addition on the growth and competitive abilities of Parmelia caperata, P. saxatilis and Xanthoria parietina. Thallus fragments were attached to roofing slates in a split-plot experimental design in monospecific and multispecific mixtures and sprayed with nutrient solution at application frequencies representing a range of nutrient enrichments. Growth rates were measured as change in thallus diameter and the strength of competition determined by counting the number of thallus overlaps. Nutrient application significantly affected thallus growth with medium application rates promoting more thallus growth than controls (distilled water) or higher application rates in all three species. Nutrient addition at medium applications significantly increased the number of thallus overlaps made by all three species compared with controls, suggesting that competition became more intense. Although symmetrical competition was observed between all three species it was noted that growth and competition of thalli in two-species mixtures could not be used to predict the result in three-species mixtures. These results suggest that elevated nutrient levels can affect lichen growth rates and competition between thalli, leading to alterations in lichen community structure.

In the mid-1950s, two distinguished Italian researchers, the mycologist Raffaele Ciferri (1895–1965) and the phytosociologist Ruggero Tomaselli (1920–1982), decided that a separate system of naming lichen mycobionts independent of the intact thalli was necessary. In this they were stimulated by the pioneering studies of Thomas (1939) in particular, which showed how different cultured isolated mycobionts appeared from whole lichen thalli. Thomas had already introduced separate names, ending in the suffix “-myces”, and they determined to introduce a comprehensive suite of generic names for lichen mycobionts in a series of papers (Tomaselli & Ciferri 1952; Ciferri & Tomaselli 1953, 1954, 1957). The numbers of generic names coined and validly published with Latin diagnoses were substantial: 15 in 1952, 203 in 1953, and a further nine in 1954. They made proposals to change the provisions of the Code, which then already ruled that names given to lichens were to be regarded as applying to their fungal components, but these were defeated and never adopted; this rule remains in the Code in Art. 13.1 (Greuter et al. 2000).