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The importance of the anatomy and fine morphology of reproductive structures for the systematics of the family Parmeliaceae is highlighted by the new genus Notoparmelia, described here for Australasian species of Parmelia. These species were known to form a monophyletic lineage but correlated characters for its delimitation were lacking. A major characteristic used here for the circumscription of this genus is the overlooked apothecial anatomy. The proper exciple is reduced to one layer formed exclusively by large hyphae without any clear branching pattern and embedded in an abundant polysaccharide matrix. This feature differs from the rest of Parmeliaceae which have a stratified three-layered proper exciple composed of a thin hyaline layer, intermediate layer and basal cortex-like structure. The anatomy of proper exciple, together with the thickness of spore walls and other morphological characters such as lobe morphology, pseudocyphellae and rhizine type, allow a precise diagnosis of the new genus. The area of distribution is also useful for characterizing this genus. Sixteen new combinations are proposed. [ABSTRACT FROM AUTHOR]

In traditional morphology-based concepts many species of lichenized fungi have world-wide distributions. Molecular data have revolutionized the species delimitation in lichens and have demonstrated that we underestimated the diversity of these organisms. The aim of this study is to explore the phylogeography and the evolutionary patterns of the Xanthoparmelia pulla group, a widespread group of one of largest genera of macrolichens. We used a dated phylogeny based on nuITS and nuLSU rDNA sequences and performed an ancestral range reconstruction to understand the processes and explain their current distribution, dating the divergence of the major lineages in the group. An inferred age of radiation of parmelioid lichens and the age of a Parmelia fossil were used as the calibration points for the phylogeny. The results show that many species of the X. pulla group as currently delimited are polyphyletic and five major lineages correlate with their geographical distribution and the biosynthetic pathways of secondary metabolites. South Africa is the area where the X. pulla group radiated during the Miocene times, and currently is the region with the highest genetic, morphological and chemical diversity. From this center of radiation the different lineages migrated by long-distance dispersal to others areas, where secondary radiations developed. The ancestral range reconstruction also detected that a secondary lineage migrated from Australia to South America via long-distance dispersal and subsequent continental radiation. [ABSTRACT FROM AUTHOR]

Abstract: The species delimitation in fungi is currently in flux. A growing body of evidence shows that the morphology-based species circumscription underestimates the number of existing species. The large and ever growing number of DNA sequence data of fungi makes it possible to use these to identify potential cases of hidden species, which then need to be studied with extensive taxon samplings. We used Parmeliaceae, one of the largest families of lichenized fungi as a model. Intra- and interspecific distances derived from maximum-likelihood phylogenetic trees inferred from 491 nuclear ITS rDNA sequences were examined for five major clades of parmelioid lichens. The intra- and interspecific distances were well separated in most cases allowing the calculation of a threshold, with exceptions of highly deviating distances in a few cases. These situations are shown to be taxa in which the current delimitation needs revision. Thus the analysis of the distance distributions is shown to be a powerful tool for identifying species complexes. [Copyright &y& Elsevier]

Disjunct intercontinental distributions have always fascinated biologists. With the increasing availability of molecular sequence data, there is a renewed interest in historical biogeography, especially in groups in which species boundaries have changed dramatically as a result, such as lichenized fungi. In the hyperdiverse family Parmeliaceae, Parmelina and Myelochroa have contrasting centres of distribution, with Myelochroa being most diverse in eastern Asia and Parmelina in Western Europe and the Mediterranean. We used multi-locus sequence data from 53 specimens to understand the impact of historical events on the current distribution patterns in these genera. We reconstructed phylogenetic relationships, estimated divergence times and inferred ancestral distributions. Our analyses suggested that the ancestor of the two genera occurred in the Old World and that these genera split during the Eocene. Diversification in both genera was estimated to have occurred during the Miocene, with the ancestor of Myelochroa probably occurring in Asia, whereas the ancestor of Parmelina probably occurred in the Turanian region and Europe or only Europe. The two Parmelina spp. occurring in the New World (P. coleae, P. yalungana) are not closely related and migrated independently from the Old World. [ABSTRACT FROM AUTHOR]

Aim: Contemporary species' distributions are shaped by both geography and historical events, such as extinction, diversification in specific areas and long‐distance dispersals. In the most diverse family of lichen‐forming fungi, Parmeliaceae, the Hypogymnioid clade, is an example of an evolutionary lineage comprised of species occurring in temperate to subpolar regions in both hemispheres. Here, we elucidate the timing of diversification events and the impact of historical events on the species distribution in this lineage. Location: Worldwide. Taxon: Genera Arctoparmelia, Brodoa, Hypogymnia and Pseudevernia (Parmeliaceae). Methods: Our sampling focused on the most diverse genus of the clade, Hypogymnia, including c. 70% of the described species. We reconstructed phylogenetic relationships using a multi‐locus data set, estimated divergence times, and inferred ancestral distributions. Results: Our analyses suggest that the ancestor of the Hypogymnioid clade occurred in the Holarctic. In each of the four genera, all recovered as monophyletic here, diversification have occurred largely during the Miocene and Pliocene. A number of currently accepted species did not form monophyletic groups, especially in cases where specimens were collected from distinct geographic areas, with multiple, distinct clades corresponding to the geographic region of origin. Our results suggest that only a very few species in the Hypogymnioid clade have cosmopolitan distributions, all of which reproduces using vegetative propagules including both symbiotic partners. Main conclusions: While the diversification occurred predominantly in the Northern Hemisphere during the Miocene, a long‐distance dispersal event from the Northern to the Southern Hemisphere, resulted in diversification of a clade of species largely restricted to the Southern Hemisphere. Similar to other groups in this diverse family, our study highlights the need for re‐evaluation of species boundaries among members of the Hypogymnioid clade. [ABSTRACT FROM AUTHOR]