Porina rivalis Orange is described as new from rocks in streams in Great Britain. The involucrellum is yellow or orange within, but dark grey to purplish red at the surface; the ascospores are 3-septate, 13·0–18·5×4·0–5·5 μm.

Tremella cetrariicola is shown to be heterogeneous and to represent two phylogenetic sister species, which are shown here to be distinct in the morphology of the galls, basidia and basidiospores, and in their host selection. Tremella cetrariicola s. str. is confined to Tuckermannopsis, whilst the material on Cetrariella delisei is described here as the new Tremella cetrariellae. The new species is known from Finland, Greenland, Norway, Russia, Svalbard, and Sweden.

The cyanolichen genus Epiphloea is currently included within the Heppiaceae (Lichinomycetes) based on ascus characteristics. The presumed presence of a prototunicate ascus has been used as support for this classification, despite the incongruence with other characters (e.g. spores). Here, we use a molecular phylogeny of the two markers mtSSU rDNA and Mcm7 to investigate the position of Epiphloea. In addition, we have re-investigated the ascus characteristics. Our results place the two species, Epiphloea byssina and E. terrena, within the Collemataceae, nested in Leptogium s. str. The ascus type in both species is shown to be Lecanoralean and similar to the ascus in other Collemataceae, with a strongly amyloid tube-like structure. This observation supports the placement within Lecanoromycetes and refutes the earlier suggested affinities with Heppiaceae and Lichinomycetes. The correct names for these species are Leptogium byssinum and Leptogium terrenum.

In a recent phylogenetic analysis of the family Teloschistaceae based on three molecular markers, 31 genera were newly described or resurrected. One of these genera was Parvoplaca, currently including four species in which anthraquinones may be present or absent in the apothecia. We have re-analyzed the genus and propose one new species, P. nigroblastidiata Arup, Halıcı & Vondrák, and one new combination, P. chelyae (Pérez-Vargas) Vondrák, Halıcı & Arup. The new species is known at present from Sweden, Turkey and Alaska. It is characterized by an endophloedal thallus, black blastidia produced in small spots and zeorin-lecanorine apothecia with an orange disc and black thalline margin. It is morphologically similar to Caloplaca turkuensis, but differs in the zeorine-lecanorine apothecia and the thalline margin that is dark grey-black instead of grey.

Bryoria araucana sp. nov. is described from Chile on the basis of morphological, chemical and molecular data. It has a grey to dark greyish brown pendent thallus with the base usually black, branching angles mainly obtuse, terminal branches with few lateral branchlets acutely inserted, fumarprotocetraric acid, and often protocetraric and confumarprotocetraric acids. It is morphologically similar to the Northern Hemisphere B. trichodes, but lacks soralia and has inconspicuous concolorous or slightly darker pseudocyphellae. Bryoria glabra is also reported for the first time from the Southern Hemisphere. New phylogenetic data based on ITS, mtSSU and MCM7 analyses suggest that Bryoria sect. Bryoria is polyphyletic and needs revision.

The lichenicolous fungi Endococcus cladiae Zhurb. & Pino-Bodas, Lichenopeltella soiliae Zhurb. & Pino-Bodas and Lichenosticta hoegnabbae Zhurb. & Pino-Bodas are described as new to science from New Zealand growing on podetia of Cladia species. In addition to their host selection, Endococcus cladiae is distinguished by its ascospore size, (9·9–)11·5–14·1(–15·7) × (2·7–)3·1–3·9(–4·6) μm, Lichenopeltella soiliae by ascomata without ostiolar setae and production of 4-spored asci and 1-septate ascospore, occasionally with three pairs of setulae, and Lichenosticta hoegnabbae by comparatively long, bacilliform to fusiform conidia, (7·8–)9·1–10·9(–12·6) × (1·9–)2·1–2·3(–2·7) μm. Niesslia cladoniicola is reported for the first time from Australasia on C. aggregata in New Zealand. A key to the lichenicolous fungi growing on Cladia is provided.

Lichenization is a symbiotic ecological strategy that is widely distributed among the fungi, but in which the diversity of partners is relatively poorly known. Limited morphological diversity has hindered the recognition of true diversity in many lichen fungi, and also in their algal partners. In the temperate and boreal zones, the crustose microlichens are the most speciose but arguably the least studied, particularly in terms of their photobiont partners. In this study, we sampled eight species of Micarea s. str. collected from Europe, culturing and sequencing their green-algal partners using chloroplast (rbcL) and nuclear ribosomal (nucSSU) markers. All specimens collected in Great Britain were associated with members of Coccomyxa (including Pseudococcomyxa), but in the smaller sample of Ukrainian material, both Coccomyxa and Elliptochloris were found. This study extends the known range of fungal hosts for symbionts in the genus Coccomyxa, and supports earlier findings that a separate lineage of predominantly non-symbiotic Coccomyxa exists.