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The new species Psoroma capense and P. esterhuyseniae are described from four alpine localities in the Western Cape Province of South Africa and are the only known Psoroma species from Africa. The specimens were all collected from moist sites near watercourses, on cool and mostly south-facing cliffs. Psoroma capense resembles P. tenue in gross morphology but differs in the ascending thallus squamules, lack of secondary compounds and short-ellipsoid to ovoid ascospores. However, a phylogenetic analysis involving the markers ITS, nucLSU, mtSSU and Mcm7, comparing the only recent collection of P. capense with previously published sequences, shows that it belongs to the P. hypnorum lineage, with no known, closely related species. Psoroma esterhuyseniae resembles P. hypnorum but has subglobose to short-ellipsoid ascospores without apical perispore extensions. The two species are thought to have evolved from one or two long-distance dispersal events during the Pleistocene. [ABSTRACT FROM AUTHOR]

The composition of lichen ecosystems except mycobiont and photobiont has not been evaluated intensively. In addition, recent studies to identify algal genotypes have raised questions about the specific relationship between mycobiont and photobiont. In the current study, we analyzed algal and fungal community structures in lichen species from King George Island, Antarctica, by pyrosequencing of eukaryotic large subunit (LSU) and algal internal transcribed spacer (ITS) domains of the nuclear r RNA gene. The sequencing results of LSU and ITS regions indicated that each lichen thallus contained diverse algal species. The major algal operational taxonomic unit (OTU) defined at a 99% similarity cutoff of LSU sequences accounted for 78.7-100% of the total algal community in each sample. In several cases, the major OTUs defined by LSU sequences were represented by two closely related OTUs defined by 98% sequence similarity of ITS domain. The results of LSU sequences indicated that lichen-associated fungi belonged to the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes, Leotiomycetes, and Sordariomycetes of the Ascomycota, and Tremellomycetes and Cystobasidiomycetes of the Basidiomycota. The composition of major photobiont species and lichen-associated fungal community were mostly related to the mycobiont species. The contribution of growth forms or substrates on composition of photobiont and lichen-associated fungi was not evident. [ABSTRACT FROM AUTHOR]

Many lichens have extensive distributional ranges covering several climatic zones and are able to colonize extreme habitats, including high alpine and polar regions. Cladonia borealis, one of the dominant lichen species on King George Island, is a cosmopolitan species inhabiting polar, subpolar, and alpine areas. It is usually found on soil, humus, and mosses, and is morphologically highly diverse. To understand the phylogeographic history of C. borealis on King George Island, we compared specimens from there with specimens from Norway and Chile. We conducted phylogenetic and haplotype network analyses of the partial SSU, ITS1-5.8S-ITS2, and partial LSU rDNA sequences including intron sequences in LSU rRNA genes. Nuclear rDNA locus of C. borealis from King George Island was separated into two monophyletic lineages. It is suggested that they originated in multiple independent introduction events after long-distance dispersal from other continents. [ABSTRACT FROM AUTHOR]