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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. [ABSTRACT FROM AUTHOR]

The lichen-forming fungal genus Flavoparmelia includes species with distinct distribution patterns, including subcos-mopolitan, restricted, and disjunct species. We used a dataset of nuclear ITS and LSU ribosomal DNA including 51 specimens to understand the influence of historical events on the current distribution patterns in the genus. We employed Bayesian, maxi-mum likelihood and maximum parsimony approaches for phylogenetic analyses, a likelihood-based approach to ancestral area reconstruction, and a Bayesian approach to estimate divergence times of major lineages within the genus. We identified two major clades in the genus, one of them separating into two subclades and one of those into four groups. Several of the groups and clades have restricted geographical ranges in the Southern Hemisphere, but two groups include species with wider distribution areas. Our analyses suggest that the genus originated in southern South America during the Eocene-Oligocene transition and that the diversification of the Australasian groups occurred recently. The subcosmopolitan distribution of species is explained by long-distance dispersal, while vicariance probably played a major role in the origin of the genus. Several currently accepted species were found to be non-monophyletic, indicating that the species delimitation in the genus requires further studies. [ABSTRACT FROM AUTHOR]

* Premise of the study: In spite of the recent advances in generic and species circumscriptions and in recognizing species diversity in lichen-forming fungi, the timing of speciation and the factors that promote diversification in lichens remain largely unexplored. We used brown parmelioids as a model to assess the timing of divergence and explore the impact of geological and climatic events on lineage divergence and diversification in lichenized fungi. Additionally, to clarify the phylogenetic position of the species currently placed in Melanelia disjuncta group, we evaluated the taxonomic status and phylogenetic relationships within Parmeliaceae. * Methods: Phylogenetic relationships and divergence time estimates were inferred from a four-loci data set. Alternative hypotheses were tested using Shimodaira-Hasegawa and expected likelihood weights tests. * Key results: The M. disjuncta group forms a strongly supported, monophyletic lineage independent from Melanelia s.s. The M. disjuncta clade arose ca. 23.1 million years ago (Ma). Our results suggest that most of the lineages within the clade diversified during the Miocene (17.6 to 11.2 Ma). The split of other brown parmelioids, such as Emodomelanelia-Melanelixia occurred ca. 41.70 Ma, and the radiation of Melanelixia began during the Eocene-Oligocene transition (ca. 33.75 Ma). * Conclusions: Montanelia is described here as a new genus to accommodate species of the Melaneliadisjuncta group. Further, the study indicates that the current species delimitation within the newly described genus requires revision. We provide evidence of lineage divergence of Montanelia at the Oligocene-Miocene boundary. Our results indicate that the diversification during Miocene would have happened during major mountain uplifts. [ABSTRACT FROM AUTHOR]

Biogeographical studies of lichens used to be complicated because of the large distribution ranges of many species. Molecular systematics has revitalized lichen biogeography by improving species delimitation and providing better information about species range limitations. This study focuses on the major clade of tropical parmelioid lichens, which share a chemical feature, the presence of isolichenan in the cell wall, and a morphological feature, microscopic pores in the uppermost layer. Our previous phylogenetic studies revealed that the largest genus in this clade, Hypotrachyna, is polyphyletic with a clade mainly distributed in South and East Asia clustering distant from the core of the genus. To divide the Hypotrachyna clade into monophyletic groups and to reevaluate morphological and chemical characters in a phylogenetic context, we sampled ITS, nuclear large subunit (nuLSU) and mitochondrial small subunit (mtSSU) rDNA sequences from 77 species. We are erecting the new genus Remototrachyna for a core group of 15 former Hypotrachyna species. The segregation of Remototrachyna from Hypotrachyna receives support from morphological and chemical data, as well from maximum parsimony, maximum likelihood, and Bayesian phylogenetic analyses of the DNA. We used a likelihood approach to study the geographic range evolution of Remototrachyna and Bulbothrix, which are sister groups. This analysis suggests that the ancestral range of Remototrachyna was restricted to India and that subsequent long-distance dispersal is responsible for the pantropical occurrence of two species of Remototrachyna. [ABSTRACT FROM AUTHOR]