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We studied the evolutionary history of the Parmeliaceae (Lecanoromycetes, Ascomycota), one of the largest families of lichen-forming fungi with complex and variable morphologies, also including several lichenicolous fungi. We assembled a six-locus data set including nuclear, mitochondrial and low-copy protein-coding genes from 293 operational taxonomic units (OTUs). The lichenicolous lifestyle originated independently three times in lichenized ancestors within Parmeliaceae, and a new generic name is introduced for one of these fungi. In all cases, the independent origins occurred c. 24 million yr ago. Further, we show that the Paleocene, Eocene and Oligocene were key periods when diversification of major lineages within Parmeliaceae occurred, with subsequent radiations occurring primarily during the Oligocene and Miocene. Our phylogenetic hypothesis supports the independent origin of lichenicolous fungi associated with climatic shifts at the Oligocene-Miocene boundary. Moreover, diversification bursts at different times may be crucial factors driving the diversification of Parmeliaceae. Additionally, our study provides novel insight into evolutionary relationships in this large and diverse family of lichen-forming ascomycetes., (© 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.)

Adaptive radiations play key roles in the generation of biodiversity and biological novelty, and therefore understanding the factors that drive them remains one of the most important challenges of evolutionary biology. Although both intrinsic innovations and extrinsic ecological opportunities contribute to diversification bursts, few studies have looked at the synergistic effect of such factors. Here we investigate the Teloschistales (Ascomycota), a group of >1,000 lichenized species with variation in species richness and phenotypic traits that hinted at a potential adaptive radiation. We found evidence for a dramatic increase in diversification rate for one of four families within this order--Teloschistaceae--which occurred ∼ 100 Mya (Late Cretaceous) and was associated with a switch from bark to rock and from shady to sun-exposed habitats. This adaptation to sunny habitats is likely to have been enabled by a contemporaneous key novel phenotypic innovation: the production in both vegetative structure (thallus) and fruiting body (apothecia) of anthraquinones, secondary metabolites known to protect against UV light. We found that the two ecological factors (sun exposure and rock substrate) and the phenotypic innovation (anthraquinones in the thallus) were all significant when testing for state-dependent shifts in diversification rates, and together they seem likely to be responsible for the success of the Teloschistaceae, one of the largest lichen-forming fungal lineages. Our results support the idea that adaptive radiations are driven not by a single factor or key innovation, but require a serendipitous combination of both intrinsic biotic and extrinsic abiotic and ecological factors.

Many black meristematic fungi persist on rock surfaces-hostile and exposed habitats where high doses of radiation and periods of desiccation alternate with rain and temperature extremes. To cope with these extremes, rock-inhabiting black fungi show phenotypic plasticity and produce melanin as cell wall pigments. The rather slow growth rate seems to be an additional prerequisite to oligotrophic conditions. At least some of these fungi can undergo facultative, lichen-like associations with photoautotrophs. Certain genera presenting different lifestyles are phylogenetic related among the superclass Dothideomyceta. In this paper, we focus on the genus Lichenothelia, which includes border-line lichens, that is, associations of melanised fungi with algae without forming proper lichen thalli. We provide a first phylogenetic hypothesis to show that Lichenothelia belongs to the superclass Dothideomyceta. Further, culture experiments revealed the presence of co-occurring fungi in Lichenothelia thalli. These fungi are related to plant pathogenic fungi (Mycosphaerellaceae) and to other rock-inhabiting lineages (Teratosphaeriaceae). The Lichenothelia thallus-forming fungi represent therefore consortia of different black fungal strains. Our results suggest a common link between rock-inhabiting meristematic and lichen-forming lifestyles of ascomycetous fungi.

Phylogenetic relationships of the lichen genus Polyblastia and closely related taxa in the family Verrucariaceae (Verrucariales, Chaetothyriomycetidae) were studied. A total of 130 sets of sequences (nuLSU rDNA, nuITS rDNA and RPB1 region A-D), including 129 newly generated sequences, were analysed. Phylogenetic relationships were inferred using a Bayesian approach based on two datasets. A first analysis of a larger, two-locus dataset (nuLSU and RPB1) for 128 members of the Verrucariaceae, confirmed the polyphyly of Polyblastia, Thelidium, Staurothele, and Verrucaria, as currently construed. The second analysis focused on 56 Polyblastia and allied taxa, but using an additional locus (nuITS rDNA) and two closely related outgroup taxa. The latter analysis revealed strongly supported groups, such as Polyblastia s. str., the Thelidium group (a mixture of Polyblastia, Thelidium, Staurothele and Verrucaria species). The genus Sporodictyon, which is here accepted, also accommodates Sporodictyon terrestre comb. nov. Morphological features traditionally used for characterizing Polyblastia, Thelidium, Staurothele and Verrucaria, such as spore septation and colour, occurrence of hymenial photobiont, involucrellum structure, and substrate preference, were found to be only partially consistent within the strongly supported clades, and thus are not always reliable features for characterizing natural groups.