About: Parmotrema is a(n) research topic. Over the lifetime, 161 publication(s) have been published within this topic receiving 2044 citation(s).
01 Dec 2010-Taxon
TL;DR: An overview of current knowledge of the major clades of all parmelioid lichens is given and 27 genera within nine main clades are accepted, including 31 of 33 currently accepted parMelioid genera (and 63 of 84 accepted genera of Parmeliaceae).
Abstract: 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.
01 Dec 2000-Zeitschrift für Naturforschung C
TL;DR: This is the first report on the isolation and characterisation of com pounds from the lichen P. stuppeum as well as on their antioxidant activity.
Abstract: Lichen, Parmotrema stuppeum (P. stuppeum) was successively extracted with benzene and acetone. Both the extracts were fractionated on 1% oxalic acid impregnated silica gel column to obtain four phenolic compounds. The structures of compounds were identified by 1H and 13C NMR spectra as methyl orsenillate, orsenillic acid, atranorin and lecanoric acid respectively. Antioxidant activity of benzene extract, acetone extract and isolated compounds were evaluated in a beta-carotene-linoleate model system. The pure compounds showed moderate antioxidant activity. This is the first report on the isolation and characterisation of compounds from the lichen P. stuppeum as well as on their antioxidant activity.
01 Jan 1993-The Bryologist
01 Jan 2005-Mycologia
TL;DR: Molecular data from three genes are employed to continue a revision of the generic concept within the parmelioid lichens and establish that this genus is closely related to Parmotrema rather than to cetrarioid species as was considered previously.
Abstract: Parmotrema is one of the larger genera segregated from Parmelia s. lat. Additional genera recently have been segregated from this large genus based mainly on morphological and chemical fea- tures. We have employed molecular data from three genes to continue a revision of the generic concept within the parmelioid lichens. A Bayesian analysis of nuclear ITS, LSU rDNA and mitochondrial SSU rDNA sequences was performed. The genera Cano- maculina, Concamerella, Parmelaria and Rimelia ap- pear nested within Parmotrema. Alternative hypothe- ses to maintain the independence of Canomaculina, Concamerella and Rimelia are shown to be highly un- likely and are rejected. As a consequence these three genera are reduced to synonymy with Parmotrema. An alternative topology segregating Parmelaria from Par- motrema s. lat. cannot be rejected with the dataset at hand. However we have established that this genus is closely related to Parmotrema rather than to cetra- rioid species as was considered previously. The re- vised genus Parmotrema includes species that have an upper cortex consisting of a palisade plectenchyma or rarely paraplectenchyma with vaults, have a pored or fenestrated epicortex, lack pseudocyphellae, have or lack cilia, have laminal, perforate or eperforate apothecia, usually have simple rhizines and filiform, cylindrical, bacilliform or sublageniform conidia. It is closely related to Flavoparmelia but the status of these genera requires further investigation. Nineteen new combinations are made.
01 Nov 2004-Mycological Progress
TL;DR: Phylogenetic relationships within the Parmeliaceae are analysed cladistically on the basis of DNA characters from partial β-tubulin, partial glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and ITS sequences to identify eight monophyletic groups.
Abstract: Phylogenetic relationships within the Parmeliaceae are analysed cladistically on the basis of DNA characters from partial β-tubulin, partial glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and ITS sequences. 100 taxa representing 73 of the 88 genera currently recognised are included in the analyses. Eight monophyletic groups including two or more genera were identified in the tree calculated from the combined data matrix. Three of the groups cover almost half of the species of the family. The largest and strongest supported group includes seven genera with their distribution centres in the Southern Hemisphere: Almbornia, Chondropsis, Karoowia, Namakwa, Neofuscelia, Xanthomaculina and Xanthoparmelia. The second group is a clade of four essentially tropical genera: Concamerella, Flavoparmelia, Parmotrema and Rimelia. The third large group with strong support is the core of cetrarioid lichens, distributed primarily in cold areas of the Northern Hemisphere. The genus Parmelia sensu Hale is not closely related with most of its segregates. One new combination, Cetrariella commixta, is proposed. Coelopogon abraxas is reported from South America for the first time.