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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]

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]

Parmelioid lichens are a diverse and ubiquitous group of foliose lichens. Generic delimitation in parmelioid lichens has been in a state of flux since the late 1960s with the segregation of the large, heterogeneous genus Parmelia into numerous smaller genera. Recent molecular phylogenetic studies have demonstrated that some of these new genera were monophyletic, some were not, and others, previously believed to be unrelated, fell within single monophyletic groups, indicating the need for a revision of the generic delimitations. This study aims to give an overview of current knowledge of the major clades of all parmelioid lichens. For this, we assembled a dataset of 762 specimens, including 31 of 33 currently accepted parmelioid genera (and 63 of 84 accepted genera of Parmeliaceae). We performed maximum likelihood and Bayesian analyses of combined datasets including two, three and four loci. Based on these phylogenies and the correlation of morphological and chemical characters that characterize monophyletic groups, we accept 27 genera within nine main clades. We re-circumscribe several genera and reduce Parmelaria to synonymy with Parmotrema. Emodomelanelia Divakar & A. Crespo is described as a new genus (type: E. masonii). Nipponoparmelia (Kurok.) K.H. Moon, Y. Ohmura & Kashiw. ex A. Crespo & al. is elevated to generic rank and 15 new combinations are proposed (in the genera Flavoparmelia, Parmotrema, Myelochroa, Melanelixia and Nipponoparmelia). A short discussion of the accepted genera is provided and remaining challenges and areas requiring additional taxon sampling are identified. [ABSTRACT FROM AUTHOR]