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Hypotrachyna is a speciose genus of primarily tropical and oceanic lichen-forming fungi. It includes species with distinct distribution patterns, such as pantropical, restricted and disjunct species. We used a dataset of mitochondrial SSU, nuclear ITS and LSU ribosomal DNA from 89 specimens to study the historical biogeography of the genus. We employed Bayesian and maximum likelihood approaches for phylogenetic analyses, a likelihood-based approach to ancestral area estimation, and a Bayesian approach to estimate divergence times of major lineages within the genus based on molecular evolutionary rates for ITS and a secondary calibration point at the Hypotrachyna clade – Parmeliopsis split. Our analyses suggest that the genus might have originated in the Neotropics during the Eocene and that the split of major lineages happened primarily during the Eocene and Oligocene. The major diversification within those clades is estimated to have occurred during the Miocene. Pantropical species distributions are explained by long-distance dispersal. A number of currently accepted species were found to be non-monophyletic, illustrating that the delimitation of species in the genus needs attention. [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]

Parmelina tiliacea is a common, widely distributed species in south-western Europe, easily identifiable by morphology and much used as an air pollution bioindicator in many regions. A molecular phylogenetic survey of samples from many geographical areas, using Maximum Parsimony and Bayesian inference of nuITS and mtLSU rDNA regions, revealed a group of samples geographically restricted to a small region of the Iberian Peninsula and genetically separated from the other P. tiliacea specimens studied. These samples are morphologically indistinguishable from P. tiliacea, apart from subtle anatomical characters in the ascomata (hyphae of the exciple and ascospore width), which are frequently absent. Although geographically different, the two taxa occupy similar habitats and are even sympatric in some areas, indicating that they do not exchange genetic material. This previously overlooked, and apparently endemic lineage, is described as P. cryptotiliacea sp. nov., and the name Lichen tiliaceus is epitypified by a sequenced specimen to fix the application of Parmelina tiliacea to the widespread genotype. A second unexpected result was the discovery that the morphologically distinct P. pastillifera was nested within P. tiliacea. These two cases stress the need to use molecular tools to elucidate species concepts even within widespread morphologically well-characterized macrolichens. Such investigations are necessary to improve our understanding and estimation of biodiversity, and to facilitate the development of sound biodiversity conservation strategies for lichens. [ABSTRACT FROM AUTHOR]