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Philippe Clerc - One of the best experts on this subject based on the ideXlab platform.
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new insights into the Usnea cornuta aggregate parmeliaceae lichenized ascomycota molecular analysis reveals high genetic diversity correlated with chemistry
Molecular Phylogenetics and Evolution, 2019Co-Authors: Alice Da Cruz Lima Gerlach, Rosa Mara Borges Da Silveira, Zeynep Toprak, Yamama Naciri, Elena Araujo Caviro, Philippe ClercAbstract:Abstract Biological processes such as hybridization, incomplete lineage sorting and gene flow can obscure the recognition of distinct evolutionary lineages, particularly in groups of organisms that have recently diverged. Therefore, compiling pieces of evidence from diverse data sources is critical to accurately assess species boundaries in such groups. The increasing availability of DNA sequence data allows for a much deeper understanding of diversification and speciation processes and their consequences on biodiversity. In this study, we applied an integrative approach based on DNA sequence, chemical, geographic and morphological data to attempt to define species boundaries in the lichen-forming genus Usnea (Parmeliaceae), particularly the U. cornuta aggregate, a cosmopolitan species group. We provide the first species delimitation for this group in the neotropics based on the multispecies coalescent (MSC) model. Using ITS rDNA and two protein-coding genes, Mcm7 and RPB1, we estimated the species tree under the MSC model in a Bayesian framework using STACEY. Our results indicate that at least nine strongly supported distinct lineages coexist in the U. cornuta aggregate, which are well chemically characterized. Additionally, we found evidence for the polyphyly of three morphospecies, Usnea brasiliensis, U. cornuta and U. dasaea.
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taxonomy of the corticolous shrubby esorediate neotropical species of Usnea adans parmeliaceae with an emphasis on southern brazil
Lichenologist, 2017Co-Authors: Alice Da Cruz Lima Gerlach, Philippe Clerc, Rosa Mara Borges Da SilveiraAbstract:Seventeen corticolous shrubby apotheciate Usnea species without vegetative propagules are reported from Brazil, including five species that are new to science: Usnea aurantiaca-parvula A. Gerlach & P. Clerc (characterized by an orange medulla and lageniform spinulose fibrils), U. cirrosa Motyka, U. cladocarpa Fee (syn. nov.: U. ramillosa Motyka), U. concinna Stirton (lectotype designated here, syn. nov. U. radiata Stirton, U. florida var. scabrosa Zahlbr.), U. cristatula Motyka, U. erinacea Vain., U. fleigiae A. Gerlach & P. Clerc (characterized by large spores and a thin, lax medulla), U. grandispora A. Gerlach & P. Clerc (characterized by large spores, a black base and protocetraric or salazinic acids in the medulla), U. kalbiana P. Clerc & A. Gerlach (characterized by a vitreous cortex and annular cracks in the basal part), U. lunaria Motyka, U. meridionalis Zahlbr. (syn. nov.: U. michauxii I. I. Tav.), Usnea cf. moreliana Motyka, U. parvula Motyka, U. steineri Zahlbr, U. subelegans (Vain.) B. de Lesd. (lectotype designated here), U. subparvula A. Gerlach & P. Clerc (characterized by spinulose fibrils and protocetraric acid in the medulla) and one as yet unidentified species (named Usnea sp. 1). Usnea cirrosa, U. cristatula and U. erinacea are new records for Brazil. A full description with morphological, anatomical (CMA and ascospores) and chemical features (TLC), as well as geographical distribution, is provided for each species along with an identification key to all species reported. Molecular data from the ITS rDNA, RPB1 and Mcm7 markers are present for most taxa, except for U. concinna, U. cristatula, U. kalbiana, U. lunaria, U. cf. moreliana and U. subelegans.
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new species and new records in the genus Usnea parmeliaceae lichenized ascomycota from tropical south america
Lichenologist, 2016Co-Authors: Camille Truong, Philippe ClercAbstract:Usnea is a cosmopolitan genus of lichen-forming Ascomycota (Parmeliaceae, Lecanorales). This hyperdiverse genus remains poorly known, especially in tropical regions, and recent efforts have been made to clarify the species concepts and describe the diversity of species. We describe five new species from tropical South America based on morphological and chemical features supported by molecular data from the ITS rDNA, nuLSU, RPB1 and Mcm7 markers. Usnea clerciana is a Galapagos endemic characterized by inflated branches holding elongated tubercles, excavate soralia and/or apothecia. Usnea aranea and U. subaranea share inflated branches with numerous papillae and a loose arachnoid medulla, but differ in the minute and irregular soralia in U. aranea, that are circular and excavate in U. subaranea. Usnea rubriglabrata and U. subglabrata are characterized by inflated branches with excavate soralia, with a reddish cortex pigmentation in U. rubriglabrata that is lacking in U. subglabrata. Usnea aranea, U. rubriglabrata, U. subaranea and U. subglabrata are so far endemic to continental South America; the three former species are closely related and cluster in a highly supported clade, characterized by species distributed in the tropical Andes. New records for the region are provided and U. moreliana is resurrected, corresponding to the valid name for U. rubricornuta.
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testing the use of its rdna and protein coding genes in the generic and species delimitation of the lichen genus Usnea parmeliaceae ascomycota
Molecular Phylogenetics and Evolution, 2013Co-Authors: Camille Truong, Pradeep K Divakar, Rebecca Yahr, Ana Crespo, Philippe ClercAbstract:In lichen-forming fungi, traditional taxonomical concepts are frequently in conflict with molecular data, and identifying appropriate taxonomic characters to describe phylogenetic clades remains challenging in many groups. The selection of suitable markers for the reconstruction of solid phylogenetic hypotheses is therefore fundamental. The lichen genus Usnea is highly diverse, with more than 350 estimated species, distributed in polar, temperate and tropical regions. The phylogeny and classification of Usnea have been a matter of debate, given the lack of phenotypic characters to describe phylogenetic clades and the low degree of resolution of phylogenetic trees. In this study, we investigated the phylogenetic relationships of 52 Usnea species from across the genus, based on ITS rDNA, nuLSU, and two protein-coding genes RPB1 and MCM7. ITS comprised several highly variable regions, containing substantial genetic signal, but also susceptible to causing bias in the generation of the alignment. We compared several methods of alignment of ITS and found that a simultaneous optimization of alignment and phylogeny (using BAli-phy) improved significantly both the topology and the resolution of the phylogenetic tree. However the resolution was even better when using protein-coding genes, especially RPB1 although it is less variable. The phylogeny based on the concatenated dataset revealed that the genus Usnea is subdivided into four highly-supported clades, corresponding to the traditionally circumscribed subgenera Eumitria, DolichoUsnea, Neuropogon and Usnea. However, characters that have been used to describe these clades are often homoplasious within the phylogeny and their parallel evolution is suggested. On the other hand, most of the species were reconstructed as monophyletic, indicating that combinations of phenotypic characters are suitable discriminators for delimitating species, but are inadequate to describe generic subdivisions.
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pendulous Usnea species parmeliaceae lichenized ascomycota in tropical south america and the galapagos
Lichenologist, 2013Co-Authors: Camille Truong, Juan Manuel Rodriguez, Philippe ClercAbstract:Eumitrioid Usnea species are characterized by a tubular central axis throughout the entire thallus. Four species were identified in South America: Usnea baileyi is a (sub-) tropical species occurring both in continental South America and the Galapagos; U. perplectata has a scattered distri- bution worldwide and occurs in continental South America, mainly on the eastern range; U. flaveola and the newly described species U. subflaveola are both so far endemic to the Neotropical Andes. Distinct chemotypes, as well as anatomical characters, such as the thickness ratio of the medulla or the presence of medullar pigmentation, are diagnostic in delimiting these species. A detailed descrip- tion of the species is provided together with an identification key.
Camille Truong - One of the best experts on this subject based on the ideXlab platform.
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new species and new records in the genus Usnea parmeliaceae lichenized ascomycota from tropical south america
Lichenologist, 2016Co-Authors: Camille Truong, Philippe ClercAbstract:Usnea is a cosmopolitan genus of lichen-forming Ascomycota (Parmeliaceae, Lecanorales). This hyperdiverse genus remains poorly known, especially in tropical regions, and recent efforts have been made to clarify the species concepts and describe the diversity of species. We describe five new species from tropical South America based on morphological and chemical features supported by molecular data from the ITS rDNA, nuLSU, RPB1 and Mcm7 markers. Usnea clerciana is a Galapagos endemic characterized by inflated branches holding elongated tubercles, excavate soralia and/or apothecia. Usnea aranea and U. subaranea share inflated branches with numerous papillae and a loose arachnoid medulla, but differ in the minute and irregular soralia in U. aranea, that are circular and excavate in U. subaranea. Usnea rubriglabrata and U. subglabrata are characterized by inflated branches with excavate soralia, with a reddish cortex pigmentation in U. rubriglabrata that is lacking in U. subglabrata. Usnea aranea, U. rubriglabrata, U. subaranea and U. subglabrata are so far endemic to continental South America; the three former species are closely related and cluster in a highly supported clade, characterized by species distributed in the tropical Andes. New records for the region are provided and U. moreliana is resurrected, corresponding to the valid name for U. rubricornuta.
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host switching promotes diversity in host specialized mycoparasitic fungi uncoupled evolution in the biatoropsis Usnea system
Evolution, 2014Co-Authors: Ana M Millanes, Paul Diederich, Camille Truong, Martin Westberg, Mats WedinAbstract:Host switching promotes diversity in host-specialized mycoparasitic fungi: uncoupled evolution in the Biatoropsis-Usnea system
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testing the use of its rdna and protein coding genes in the generic and species delimitation of the lichen genus Usnea parmeliaceae ascomycota
Molecular Phylogenetics and Evolution, 2013Co-Authors: Camille Truong, Pradeep K Divakar, Rebecca Yahr, Ana Crespo, Philippe ClercAbstract:In lichen-forming fungi, traditional taxonomical concepts are frequently in conflict with molecular data, and identifying appropriate taxonomic characters to describe phylogenetic clades remains challenging in many groups. The selection of suitable markers for the reconstruction of solid phylogenetic hypotheses is therefore fundamental. The lichen genus Usnea is highly diverse, with more than 350 estimated species, distributed in polar, temperate and tropical regions. The phylogeny and classification of Usnea have been a matter of debate, given the lack of phenotypic characters to describe phylogenetic clades and the low degree of resolution of phylogenetic trees. In this study, we investigated the phylogenetic relationships of 52 Usnea species from across the genus, based on ITS rDNA, nuLSU, and two protein-coding genes RPB1 and MCM7. ITS comprised several highly variable regions, containing substantial genetic signal, but also susceptible to causing bias in the generation of the alignment. We compared several methods of alignment of ITS and found that a simultaneous optimization of alignment and phylogeny (using BAli-phy) improved significantly both the topology and the resolution of the phylogenetic tree. However the resolution was even better when using protein-coding genes, especially RPB1 although it is less variable. The phylogeny based on the concatenated dataset revealed that the genus Usnea is subdivided into four highly-supported clades, corresponding to the traditionally circumscribed subgenera Eumitria, DolichoUsnea, Neuropogon and Usnea. However, characters that have been used to describe these clades are often homoplasious within the phylogeny and their parallel evolution is suggested. On the other hand, most of the species were reconstructed as monophyletic, indicating that combinations of phenotypic characters are suitable discriminators for delimitating species, but are inadequate to describe generic subdivisions.
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pendulous Usnea species parmeliaceae lichenized ascomycota in tropical south america and the galapagos
Lichenologist, 2013Co-Authors: Camille Truong, Juan Manuel Rodriguez, Philippe ClercAbstract:Eumitrioid Usnea species are characterized by a tubular central axis throughout the entire thallus. Four species were identified in South America: Usnea baileyi is a (sub-) tropical species occurring both in continental South America and the Galapagos; U. perplectata has a scattered distri- bution worldwide and occurs in continental South America, mainly on the eastern range; U. flaveola and the newly described species U. subflaveola are both so far endemic to the Neotropical Andes. Distinct chemotypes, as well as anatomical characters, such as the thickness ratio of the medulla or the presence of medullar pigmentation, are diagnostic in delimiting these species. A detailed descrip- tion of the species is provided together with an identification key.
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the lichen genus Usnea parmeliaceae in tropical south america species with a pigmented medulla reacting c yellow
Lichenologist, 2012Co-Authors: Camille Truong, Philippe ClercAbstract:In tropical South America (Venezuela, Colombia, Ecuador, Peru, Bolivia and Brazil), we investigated the diversity of Usnea species with a pigmented, C+ yellow medulla. Four species are treated: the sorediate U. ceratina and U. entoviolata, the latter being new for South America, and the non-sorediate U. cristatula and U. flavorubescens, the latter being newly described here. A detailed description is provided for each species together with an identification key.
Rodríguez, Juan Manuel - One of the best experts on this subject based on the ideXlab platform.
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Pendulous Usnea species (Parmeliaceae, lichenized Ascomycota) in tropical South America and the Galapagos
2017Co-Authors: Truong Camille, Rodríguez, Juan Manuel, Clerc PhilippeAbstract:The diversity of pendulous Usnea species in tropical South America (Bolivia, Brazil, Colombia, Ecuador, Paraguay, Peru and Venezuela) and the Galapagos Islands is discussed with reference to 23 species. Usnea crenulata Truong & Clerc is newly described. Usnea articulata, U. deformis, U. dimorpha, U. geissleriana, U. merrillii, U. perhispidella, U. sanctaeritae, U. subflammea and U. transitoria are newly reported for South America. Modern descriptions are provided for Usnea amabilis, U. arthroclada, U. dodgei, U. humboldtii and U. regia. We propose to reject the synonymy of U. hesperina with U. schadenbergiana, and the valid name for U. hesperina is therefore U. subgracilis. Distinct patterns of unidentified triterpenoids have been detected by thin-layer chromatography and are used to characterize several species within this group. The morphology, branch anatomy, chemistry, ecology and distribution of each species are given, together with an identification ke
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Nuevas citas de macrolíquenes para Argentina y ampliaciones de distribución en el centro del país.
Sociedad Argentina de Botánica, 2016Co-Authors: Rodríguez, Juan Manuel, Hernández, Juan Martin, Filippini Edith, Cañas Martha, Estrabou CeciliaAbstract:New records of macrolichens and increasing distributional range in central Argentina. Four species of lichenized Ascomycetes are mentioned for the first time from Argentina: Endocarpon pallidulum, Placidium arboreum, Pyxine astridiana and Usnea michauxii. A brief description of each one is presented considering morphological, anatomical and chemical characteristics. The distribution of 68 lichen species in Argentina is also extended. Se mencionan por primera vez para el país cuatro especies de Ascomycetes liquenizados: Endocarpon pallidulum, Placidium arboreum, Pyxine astridiana y Usnea michauxii. Se presenta una breve descripción de cada una considerando características morfológicas, anatómicas y químicas. A su vez se amplía la distribución de 68 especies de líquenes en el centro de Argentina
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Nuevas citas de macrolíquenes para Argentina y ampliación de distribución del centro del país
Sociedad Argentina de Botánica, 2016Co-Authors: Rodríguez, Juan Manuel, Hernández, Juan Martin, Filippini, Edith Raquel, Cañas, Martha Susana, Estrabou CeciliaAbstract:Se mencionan por primera vez para el país cuatro especies de Ascomycetes liquenizados: Endocarpon pallidulum, Placidium arboreum, Pyxine astridiana y Usnea michauxii. Se presenta una breve descripción de cada una considerando características morfológicas, anatómicas y químicas. A su vez se amplía la distribución de 68 especies de líquenes en el centro de Argentina.New recors of microlichensand increasing distributional range in central Argentina. Four species of lichenized ascomycetes are mentioned from the first time from Argentina.Endocarpon pallidulum, Placidium arboreum, Pyxine astridianaand Usnea michauxii.A brief description of each one is presented, considering morphological, anatomical and chemical characteristics.The distyribution of 68 lichen species in Argentina is also extended.Fil: Rodriguez, Juan Manuel. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; ArgentinaFil: Hernández, Juan Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Filippini, Edith Raquel. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; ArgentinaFil: Cañas, Martha Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Estrabou, Cecilia. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Ecología y Recursos Naturales Renovables; Argentin
Mario J Simirgiotis - One of the best experts on this subject based on the ideXlab platform.
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secondary metabolite profiling of species of the genus Usnea by uhplc esi ot ms ms
Molecules, 2017Co-Authors: Francisco Salgado, Laura Albornoz, Carmen Cortez, Elena E Stashenko, Kelly Urreavallejo, Edgar Nagles, Cesar Galiciavirviescas, Alberto Cornejo, Alejandro E Ardiles, Mario J SimirgiotisAbstract:Lichens are symbiotic associations of fungi with microalgae and/or cyanobacteria, which are considered among the slowest growing organisms, with strong tolerance to adverse environmental conditions. There are about 400 genera and 1600 species of lichens and those belonging to the Usnea genus comprise about 360 of these species. Usnea lichens have been used since ancient times as dyes, cosmetics, preservatives, deodorants and folk medicines. The phytochemistry of the Usnea genus includes more than 60 compounds which belong to the following classes: depsides, depsidones, depsones, lactones, quinones, phenolics, polysaccharides, fatty acids and dibenzofurans. Due to scarce knowledge of metabolomic profiles of Usnea species (U. barbata, U. antarctica, U. rubicunda and U. subfloridana), a study based on UHPLC-ESI-OT-MS-MS was performed for a comprehensive characterization of their secondary metabolites. From the methanolic extracts of these species a total of 73 metabolites were identified for the first time using this hyphenated technique, including 34 compounds in U. barbata, 21 in U. antarctica, 38 in U. rubicunda and 37 in U. subfloridana. Besides, a total of 13 metabolites were not identified and reported so far, and could be new according to our data analysis. This study showed that this hyphenated technique is rapid, effective and accurate for phytochemical identification of lichen metabolites and the data collected could be useful for chemotaxonomic studies.
Paul A Keller - One of the best experts on this subject based on the ideXlab platform.
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phytochemical and pharmacological studies on four indonesian epiphytic medicinal plants drynaria rigidula hydnophytum formicarum Usnea misaminensis and calymperes schmidtii
Natural Product Communications, 2019Co-Authors: Ari Satia Nugraha, Tashi Wangchuk, Anthony C Willis, Rachada Haritakun, Heri Sujadmiko, Paul A KellerAbstract:Phytochemical studies performed on 4 Indonesian epiphytic medicinal plants, Drynaria rigidula L., Hydnophytum formicarum Jack, Usnea misaminensis (Vain) Motyka, and Calymperes schmidtii Broth., rev...
