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The widespread species Parmotrema crinitum (Ach.) M. Choisy and Parmotrema perlatum (Huds.) M. Choisy are mainly distinguished by their reproductive strategies. While P. crinitum propagates by isidia, P. perlatum produces soredia. In this study, we aim to evaluate the phylogenetic relationship between both species and to critically examine their species boundaries. To this purpose, 46 samples belonging to P. crinitum and P. perlatum were used in our analysis, including 22 for which we studied the morphology and chemistry, before extracting their DNA. We used 35 sequences of the internal transcribed spacer region of nuclear ribosomal DNA (ITS) of Parmotrema perlatum from Europe and Africa (20 of which were newly generated), and 11 of Parmotrema crinitum from Europe, North America and North Africa (two newly generated). Additionally, 28 sequences of several species from Parmotrema were included in the ITS dataset. The ITS data matrix was analyzed using different approaches, such as traditional phylogeny (maximum likelihood and Bayesian analyses), genetic distances, automatic barcode gap discovery (ABGD) and the coalescent-based method poisson tree processes (PTP), in order to test congruence among results. Our results indicate that all samples referred to P. crinitum and P. perlatum nested in a well-supported monophyletic clade, but phylogenetic relationships among them remain unresolved. Delimitations inferred from PTP, ABGD and genetic distance analyses were comparable and suggested that P. crinitum and P. perlatum belong to the same lineage. Interestingly, two samples of P. perlatum separate in a different monophyletic clade, which is supported as a different lineage by all the analyses. [ABSTRACT FROM AUTHOR]

Tropical regions harbor rich biodiversity but are relatively poorly explored, especially in lesser known taxonomic groups, such as lichenized fungi. In addition, the identification of species is complicated by frequent occurrence of cryptic species and the plasticity of phenotypic features traditionally used to identify species. Here, we aim to explore species diversity and provide tools for accurate sample identification of the genus Parmotrema from rainforests in Thailand. We gathered a three-locus DNA sequence data set and this was analysed in phylogenetic and DNA barcode frameworks. While some morpho-species were recovered as monophyletic, others did not form monophyletic groups. Our study unmasked cryptic lineages in Parmotrema species distributed in the tropics and show that phenotype-based sample identification may underestimate species diversity in this group of lichens. Further, genetic distances based on ITS DNA sequences (i.e. DNA barcode approach) were shown to be a valuable tool for sample identification. In addition, our study highlights the need for taxonomic reexamination of the following phenotypically delimited species: P. corniculans, P. crinitum, P. haitiense, P. maclayanum, P. perlatum and P. subtinctorium. [ABSTRACT FROM AUTHOR]

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]

Asexual species with vegetative propagation of both symbiont partners (soredia) in lichens may harbor lower species diversity because they may indeed represent evolutionary dead ends or clones. In this study we aim to critically examine species boundaries in the sorediate lichen forming fungi Parmotrema reticulatum–Parmotrema pseudoreticulatum complex applying coalescent-based approaches and other recently developed DNA-based methods. To this end, we gathered 180 samples from Africa, Asia, Australasia, Europe, North and South America and generated sequences of internal transcribed spacer of nuclear ribosomal DNA (ITS) and DNA replication licensing factor MCM7 (MCM7). The dataset was analysed using different approaches such as traditional phylogeny–maximum likelihood and Bayesian–genetic distances, automatic barcode gap discovery and coalescent-based methods–PTP, GMYC, spedeSTEM and *Beast–in order to test congruence among results. Additionally, the divergence times were also estimated to elucidate diversification events. Delimitations inferred from the different analyses are comparable with only minor differences, and following a conservative approach we propose that the sampled specimens of the P. reticulatum–P. pseudoreticulatum complex belong to at least eight distinct species-level lineages. Seven are currently classified under P. reticulatum and one as P. pseudoreticulatum. In this work we discuss one of only few examples of cryptic species that have so far been found in sorediate reproducing lichen forming fungi. Additionally our estimates suggest a recent origin of the species complex–during the Miocene. Consequently, the wide distribution of several of the cryptic species has to be explained by intercontinental long-distance dispersal events. [ABSTRACT FROM AUTHOR]

Accurate specimen identification is challenging in groups with subtle or scarce taxonomically diagnostic characters, and the use of DNA barcodes can provide an effective means for consistent identification. Here, we investigate the utility of DNA barcode identification of species in a cosmopolitan genus of lichen-forming fungi, Parmelia (Parmeliaceae). Two hundred and two internal transcribed spacer (ITS) sequences generated from specimens collected from all continents, including Antarctica, were analysed, and DNA barcodes of 14 species of Parmelia s.s. are reported. Almost all species show a barcode gap. Overall, intraspecific divergence values were lower than the threshold previously established for Parmeliaceae. However, the mean and range were elevated by deep barcode divergences in three species, indicating the likely occurrence of overlooked specieslevel lineages. Here, we provide a DNA barcode reference library with well-identified specimens sampled worldwide and sequences from most of the type material to enable easy and fast accurate sample identification and to assist in uncovering overlooked species in Parmelia s.s. Further, our results confirm the efficiency of the ITS region in the identification of species of Parmelia s.s. [ABSTRACT FROM AUTHOR]

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]

In the last decade, a number of cryptic species have been discovered in lichenized fungi, especially in species with a cosmopolitan or disjunctive distribution. Parmelia saxatilis is one of the most common and widely distributed species. Recent molecular studies have detected two species, P. ernstiae and P. serrana, within P. saxatilis s. lat., suggesting the existence of considerable genetic diversity that may not yet be expressed at the phenotypic level. Due to the complexity in the P. saxatilis s. lat. group, we used this as a model to study the species boundary and identify cryptic lineages. We used Phylogenetic (Bayes, ML and MP) and genetic distance approaches to analyze ITS and β-tubulin sequences. Our results confirm the existence of another cryptic lineage within P. saxatilis s. lat. This lineage is described herein as a new species, P. mayi. It forms an independent, strongly supported, monophyletic lineage, distantly related to the morphologically similar species P. ernstiae, P. saxatilis and P. serrana. Morphologically, it is indistinguishable from P. saxatilis but the new species is separated by molecular, bioclimatic, biogeographic and chemical characters. At present, P. mayi appears to have a restricted distribution in the northern Appalachian mountain territories of North America. It is found in climatic conditions ranging from hemiboreal and orotemperate to cryorotemperate ultrahyperhumid bioclimates. [ABSTRACT FROM AUTHOR]

Recently, the number of cryptic species known has increased considerably, showing that species diversity has in many cases been underestimated in the past. Parmelia sulcata is a widely distributed species and one of the most common taxa in temperate Europe. The first intra-specific molecular studies on P. sulcata showed an unexpectedly high genetic variability. In the present work, we study the biodiversity of this taxon including specimens from four continents and using three molecular markers (nuITS, nuIGS rDNA, and partial β-tubulin gene). Two monophyletic groups of P. sulcata were encountered; one of these is epitypified as P. sulcata s. str and the other one is segregated as the new cryptic species P. encryptata sp. nov. Issues surrounding the lectotypification of Parmelia sulcata have also been elucidated. [ABSTRACT FROM AUTHOR]

We used a genetic distance approach in conjunction with molecular phylogeny to establish species boundaries and detect cryptic lineages in the Parmotrema reticulatum – P. pseudoreticulatum complex. The phylogeny of specimens from a broad geographic distribution was reconstructed from the internal transcribed spacer region. Pairwise genetic distances were calculated and compared to an intraspecific range defined for the parmelioid lichens to circumscribe species-level groups. Our results showed that P. reticulatum and P. pseudoreticulatum are polyphyletic, being comprised of at least seven well-supported lineages. In contrast, the genetic distance approach revealed ten cryptic lineages within the P. reticulatum – P. pseudoreticulatum complex. Neither morphology nor geography was conclusive in attempting to corroborate these genetic lineages. However FST indices suggest significant genetic differentiation between these lineages. Our results suggest that the morphology-based circumscriptions underestimated species in Parmotrema and that, in some cases, genetic distances may be used as an additional tool to determine species boundaries in morphologically cryptic species complexes. The most significant contribution of the present study is the application of a fast and accurate method to identify problematic groups and candidate species using the ITS locus with a genetic distances approach. [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]

This study focuses on European Usnea species with sorediate shrubby thalli, with the aim to evaluate the morphological and chemical separation of species in the light of molecular data. Twenty-two Usnea species, including widely distributed taxa such as U. diplotypus, U. fulvoreagens, U. glabrescens, U. lapponica, U. subfloridana, U. substerilis and U. wasmuthii, were included in the study using Bayesian and maximum parsimony analyses of nuclear ITS and beta-tubulin sequences. The analyses showed that: 1) most taxa that are morphologically well delimited are also distinct by means of molecular characters, 2) shrubby taxa in the section Usnea that are difficult to determine by traditional characters form a group of closely related but still genetically distinct entities, except U. diplotypus and U. substerilis which appear to be polyphyletic. The branch lengths differed largely between two parts of the ITS tree (sections Usnea and Ceratinae). Usnea intermedia is proposed as the sexually reproducing counterpart for the sorediate U. lapponica. Additionally, some new chemotypes of Usnea species were determined. [ABSTRACT FROM AUTHOR]

Two asexual reproductive strategies of the common lichen Pseudevernia furfuracea are described. Although the species propagates mainly by isidia, some specimens also show the development of soralia. Morphological, chemical and molecular analyses were performed on three such sorediate specimens from the Canary Islands, Morocco and Turkey. Maximum parsimony, maximum likelihood and Bayesian analyses indicate that: a) sorediate samples represent only a morphological variant of the reproductive mode and b) the separation of taxa (at species level or below) on the basis of their containing either olivetoric acid or physodic and oxyphysodic acids is not appropriate. In addition, a phylogenetic reconstruction of the genus Pseudevernia is presented for the first time. The tree shows two sister monophyletic clades, one containing American species (P. intensa, P. cladonia, P. consocians), and the second encompassing the P. furfuracea samples (including sorediate specimens). The biological and taxonomic significance of soralia in sorediate samples is discussed. [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]

Morphological and phylogenetic relationships of the worldwide Mediterranean lichen forming fungus, Parmelina quercina, have been studied. Specimens from western Europe, western North America and southern Australia were analysed using molecular data (nuITS rDNA, nuLSU rDNA and mtSSU rDNA) and selected morphological features (upper cortex maculae, scanning electron microscopy examination of the epicortex, ascospores and conidia shape and size, and amphithecial retrorse rhizines). The results conclusively reveal that: (1) there is not one single species but four separate species in the Mediterranean or sub Mediterranean areas of the world. Parmelina quercina and Parmelina carporrhizans (Euroasiatic species), Parmelina coleae sp. nov. (North America) and Parmelina elixia sp. nov. (Australia); (2) largely debated P. carporrhizans is not a synonym of P. quercina but supported as a valid species circumscribed to Macaronesic relict sites; (3) the geographical isolation of the Australian population is correlated with a large genetic distance; (4) morphological characters (ascospores and conidial variability and thallus epicortex) correlate with the phylogenetic hypothesis; (5) the new or revalidated species within Parmelina quercina are not cryptic species but morphologically recognizable taxa. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 91, 455–467. [ABSTRACT FROM AUTHOR]

The phylogenetic position of the European crustose pioneer lichen Moelleropsis (Biatora) humida (Kullhem) Coppins & P. M. Jørg. is studied using partial sequences of the mitochondrial SSU and nuclear LSU rDNA of 64 ascomycetes, including sequences of all known species of Arctomiaceae. The analysis places M. humida in the Arctomiaceae with strong support as sister to the Tasmanian genus Wawea. The genus Arctomia is monophyletic and sister-group to the Wawea+Moelleropsis humida clade. The new genus Gregorella is described to accommodate Moelleropsis humida and the new combination Gregorella humida (Kullhem) Lumbsch is proposed. The ontogeny of the ascomata of Gregorella humida is similar to that of other Arctomiaceae, in that the generative tissue is formed on a thallus outgrowth. The Arctomiaceae did not cluster with the bulk of cyanobacterial lichens in the Lecanorales suborder Peltigerineae (or Peltigerales), but is part of Ostropomycetidae. The closest relative of Arctomiaceae could not be identified, since the relationships of major clades within Ostropomycetidae lacked support. [ABSTRACT FROM AUTHOR]