Usnea Research Articles

Lichen Mycota in South Korea: The Genus Usnea

Usnea Adans. is a somewhat rare lichen in South Korea, and, in nearly two decades, no detailed taxonomic or revisionary study has been conducted. This study was based on the specimens deposited in the lichen herbarium at the Korean Lichen Research Institute, and the samples were identified using information obtained from recent literature. In this study, a total of eight species of Usnea, including one new record, Usnea hakonensis Asahina, are documented. Detailed descriptions of each species with their morphological, anatomical, and chemical characteristics are provided. A key to all known Usnea species in South Korea is also presented.

Testing the use of ITS rDNA and protein-coding genes in the generic and species delimitation of the lichen genus Usnea (Parmeliaceae, Ascomycota)

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.

Five Apothecium-producing Lichenized Fungi of the Genus Usnea in Taiwan

Most species of the genus Usnea that commonly produce apothecia in Taiwan have not been collected for a long time. We rediscovered five species, including Usnea masudana, U. orientalis, U. pseudogatae, U. shimadae, and U. sinensis, by investigating their morphology, chemistry, and molecular data. Ten internal transcribed spacer (ITS) sequences of the five species were first reported. Distributions of the species were also provided. Although no latitudinal tendency was observed among the Usnea species in Taiwan, we consider high elevation places of the subtropics and tropics to contain plenty of Usnea species that produce apothecia.

Using haplotype networks, estimation of gene flow and phenotypic characters to understand species delimitation in fungi of a predominantly Antarctic Usnea group (Ascomycota, Parmeliaceae)

Species delimitations in the predominantly Antarctic and South American group of neuropogonoid species of the lichen-forming fungal genus Usnea are poorly understood. Morphological variability has been interpreted as a result of harsh ecological conditions, but preliminary molecular data have led to doubts about the current species delimitations in these lichenized fungi. We examined species boundaries using a phylogenetic approach and a cohesion species recognition method generating haplotype networks and looking at associations of phenotypic characters with clades found in the networks. In addition, we estimated gene flow among detected clades and currently circumscribed species. We identified several clades that were significantly associated with phenotypic characters, but did not necessarily agree with current species circumscriptions. In one case (U. aurantiaco-atra/U. antarctica), network analysis and the estimation of gene flow provided no evidence of distinct species. The distinctness of another species pair (U. subantarctica/U. trachycarpa) remains dubious, showing evidence for gene flow among currently accepted species.

The influence of host tree morphology and stem size on epiphyte biomass distribution in Lusenga Plains National Park, Zambia

The influence of host tree morphology and stem size on epiphyte biomass distribution in host trees was assessed in Lusenga Plains National Park, Zambia for the period 2004 to 2007. A total of 8 ha were sampled in bush land, woodland and riparian forest vegetation communities. Epiphytes were collected, dried and weighed to obtain biomass, which was apportioned between different host tree species, vertical and horizontal branches, crown and trunk, and small, medium, and large stems, as well as smooth and rough bole textured substrates. Horizontal branches had more epiphytes, 50% than vertical branches (17%). Tree canopies had more epiphyte biomass, 68% than trunks (32%). In riparian forestsUsnea articulata and Ramalina reticulata were not selective. In Miombo woodlands, epiphytes and certain tree species with larger stems and rough bore texture were selected. Larger substrates dbh > 100 cm had higher epiphyte biomass (94.46%) followed by medium dbh 51 to 100 cm (5.29%) and the least was on small girth dbh ≥ 20 to 50 cm (0.25%). Rough substrates had 89% biomass and only 11% occurred on smooth bole substrates. It was concluded that tree crowns, horizontal stems and branches, large and rough bole textured tree substrates provided suitable habitat for epiphyte seed settling, germination and moisture retention, while exposure to sunlight supported germination and growth of epiphytes. Maintenance of mature Miombo woodlands was therefore found to be critical in maintaining epiphytes, while protection of preferred tree species would ensure their long-term survival and sustenance of hydrologic functions. Key words: Epiphyte, host, pattern, biomass, crown, trunk, horizontal, vertical.

DNA barcoding of lichenized fungi demonstrates high identification success in a floristic context

• Efforts are currently underway to establish a standard DNA barcode region for fungi; we tested the utility of the internal transcribed spacer (ITS) of nuclear ribosomal DNA for DNA barcoding in lichen-forming fungi by sampling diverse species across eight orders. • Amplification of the ITS region (ITS1-5.8S-ITS2) was conducted for 351 samples, encompassing 107, 55 and 28 species, genera and families, respectively, of lichenized fungi. We assessed the ability of the entire ITS vs the ITS2 alone to discriminate between species in a taxonomic dataset (members of the genus Usnea) and a floristic dataset. • In the floristic dataset, 96.3% of sequenced samples could be assigned to the correct species using ITS or ITS2; a barcode gap for ITS is present in 92.1% of species. Although fewer species have a barcode gap in the taxonomic dataset (73.3% with ITS and 68.8% with ITS2), up to 94.1% of samples were assigned to the correct species using BLAST. • While discrimination between the most closely related species will remain challenging, our results demonstrate the potential to identify a high percentage of specimens to the correct species, and the remainder to the correct genus, when using DNA barcoding in a floristic context.

Виды рода Usnea (Parmeliaceae) в Республике Бурятия

Species distribution and composition of the genus Usnea in Buryatia Republic (Russia) are discussed. Records of 11 Usnea species were cited for Buryatia in literature, 10 of them have been confirmed by examination of herbarium materials. Morphological changes of thallus growth pattern (shortening of main branches and increasing number of fibrils and lateral branches resulting in formation of brush-like thalli) in extracontinental environment are described.

HPLC determination of usnic acid content in different extracts of Usnea barbata

Lichens are important sources of biologically active compounds. Beard lichen, Usnea barbata L. (Parmeliaceae) grows on the bark of host trees in the Northern hemisphere of Europe, Asia and America [1]. Lichens containing usnic acid are traditionally used in China and other parts of the world, for medicinal and cosmetic purposes, as well as in homeopathy. Usnic acid exhibits antimicrobial, antiviral, antiprotozoal, antiproliferative, anti-inflammatory, analgesic and antipyretic activities [2].

Bioactive secondary metabolites from an Endolichenic Fungus, Corynespora sp. inhabiting the Cavern beard Lichen, Usnea cavernosa

Bioactive secondary metabolites of an endolichenic fungal strain, Corynespora sp., occurring in the beard cavern lichen Usnea cavernosa (cavern beard lichen; Parmeliaceae; Lecanorales), was investigated. Although a number of lichens, their fungal mycobionts, and a lichenicolous fungus from different geographic locations have been subjected to chemical investigations, leading to the isolation and characterization of a variety of metabolites, to the best our knowledge this constitutes the first report of secondary metabolites from an endolichenic fungus. An EtOAc extract of Corynespora sp. cultured in potato dextrose broth (PDB) exhibited significant cell migration inhibitory activity in a wound-healing assay (WHA) using the metastatic prostate cancer cell line, PC-3M, at a noncytotoxic concentration of 5 µg/mL. We report the bioassay-guided isolation of two new heptaketides, corynesporol (1) and 1-hydroxydehydroherbarin (2), together with herbarin (3) and the chemical transformation of 1-3 yielding compounds, dehydroherbarin (4) and four new acetylated derivatives of the heptadetides. The structures of 1–4 and the acetylated derivatives were elucidated by spectroscopic methods and all compounds were evaluated for their cytotoxicity and ability to inhibit migration of human metastatic breast and prostate cancer cell lines MDA-MB-231 and PC-3M, respectively. Dehydroherbarin (4) inhibited migration of both cell lines at concentrations not toxic to these cell lines.

Heptaketides from Corynespora sp. Inhabiting the Cavern Beard Lichen, Usnea cavernosa: First Report of Metabolites of an Endolichenic Fungus

Two new heptaketides, corynesporol (1) and 1-hydroxydehydroherbarin (2), along with herbarin (3) were isolated from an endolichenic fungal strain, Corynespora sp. BA-10763, occurring in the cavern beard lichen Usnea cavernosa. The structures of 1-3 were elucidated from their spectroscopic data. Aerial oxidation of corynesporol (1) yielded herbarin (3). Acetylation of 1 afforded the naphthalene derivative 4, whereas acetylation of 3 gave the corresponding naphthoquinone 6 and dehydroherbarin (5). All compounds were evaluated for their cytotoxicity and ability to inhibit migration of human metastatic breast and prostate cancer cell lines MDA-MB-231 and PC-3M, respectively. Dehydroherbarin (5) inhibited migration of both cell lines at concentrations not toxic to these cell lines. This is the first report of metabolites from an endolichenic fungus.

Saturated Solution of PbSO4 as Standard Stock Solution and Its Applications in Analytical Spectroscopy: Screening Analysis of Lead in Natural Water and Usnea longissima

A saturated PbSO4 aqueous solution, which was prepared by dissolving commercially available solid PbSO4 in doubly distilled water, was employed as a standard stock solution of lead for the visual colorimetric determination of lead in water and atomic fluorescence spectrometric determination of lead in whole Usnea longissima (i.e., Methuselah's beard lichen). The concentration of lead in this saturated solution is theoretically calculated to 27.8 mg/L by using the solubility product constant of PbSO4 at 25°C. The standard solution series is by further dilution of the saturated solution. A validation experiment proved the feasibility of using the saturated solution as the standard stock solution of lead. The experimental conditions, mainly the temperature, that affect the equilibrium of precipitation–dissolution in the saturated solution were investigated. The saturated PbSO4 solution was proved to be accurate enough for the purpose of screening analysis of lead in these samples.

Climate change manipulations show Antarctic flora is more strongly affected by elevated nutrients than water

AbstractClimate change is expected to affect the high latitudes first and most severely, rendering Antarctica one of the most significant baseline environments for the study of global climate change. The indirect effects of climate warming, including changes to the availability of key environmental resources, such as water and nutrients, are likely to have a greater impact upon continental Antarctic terrestrial ecosystems than the effects of fluctuations in temperature alone. To investigate the likely impacts of a wetter climate on Antarctic terrestrial communities a multiseason, manipulative field experiment was conducted in the floristically important Windmill Islands region of East Antarctica. Four cryptogamic communities (pure bryophyte, moribund bryophyte, crustose and fructicose lichen‐dominated) received increased water and/or nutrient additions over two consecutive summer seasons. The increased water approximated an 18% increase in snow melt days (0.2°C increase in temperature), while the nutrient addition of 3.5 g N m−2 yr−1 was within the range of soil N in the vicinity. A range of physiological and biochemical measurements were conducted in order to quantify the community response. While an overall increase in productivity in response to water and nutrient additions was observed, productivity appeared to respond more strongly to nutrient additions than to water additions. Pure bryophyte communities, and lichen communities dominated by the genus Usnea, showed stronger positive responses to nutrient additions, identifying some communities that may be better able to adapt and prosper under the ameliorating conditions associated with a warmer, wetter future climate. Under such a climate, productivity is overall likely to increase but some cryptogamic communities are likely to thrive more than others. Regeneration of moribund bryophytes appears likely only if a future moisture regime creates consistently moist conditions.

Synopsis of Usnea (lichenized Ascomycetes) from the Azores with additional information on the species in Macaronesia

The genus Usnea is a conspicuous component of the macrolichen vegetation in Macaronesia. Ten species are recognized in the Azorean archipelago: Usnea cornuta Körb., U. esperantiana P. Clerc, U. flammea Stirt., U. geissleriana P. Clerc sp. nov., U. krogiana P. Clerc sp. nov., U. macaronesica P. Clerc sp. nov., U. rubicunda Stirt., U. silesiaca Motyka, U. subflammea P. Clerc sp. nov., and U. subscabrosa Motyka. All these species occur in the Canary Islands as well. Descriptive, chemical, ecological and distributional data for each species are provided. Species that have been recorded once for the Azores but not seen, or that are doubtful or excluded in this work, are briefly discussed.

Nomenclature and Typification in the Genus Usnea (Lichenized Ascomcyetes). – V. Usnea hesperina Motyka

ABSTRACT A lectotype is selected for Usnea hesperina, overturning the previously selected neotype.

Nomenclature and typification in the genus Usnea (lichenized Ascomycetes)—II. Usnea fallax and Usnea paradoxa

Abstract Continued work on the angulose species of the genus Usnea has led to the discovery that the names Usnea fallax Motyka and U. paradoxa (Zahlbruckner) Motyka have been confused and incorrectly typified. Thus, here the following changes are implied: Usnea angulata Acharius var. paradoxa Zahlbruckner is lectotypified and placed in synonymy with U. fallax Motyka; the authorship of U. paradoxa (Zahlbruckner) Motyka should be cited as U. paradoxa Motyka; and U. paradoxa Motyka is lectotypified. The corrected use of both names is presented and the type material is illustrated.

Taxonomic study of the genus Usnea (lichenized Ascomycetes) in Japan and Taiwan

Taxonomic study of the genus Usnea (lichenized Ascomycetes) in Japan and Taiwan

The Lichen Genus Usnea On Quercus Suber In Iberian Cork-Oak Forests

Fifteen species of Usnea are recorded from Iberian cork-oak forests: U. ceratina, U. comma, U. dasaea, U. esperantiana, U. flammea, U. fulvoreagens, U. glabrata, U. hirta, U. mutabilis, U. rubicunda, U. subcornuta, U. subfloridana U. subscabrosa, U. substerilis and U. wasmuthii. A key for these species is provided. Details of morphology, chemistry, distribution, ecology and taxonomy are discussed. Usnea dasaea is reported as new to the Iberian Peninsula. New chemotypes of U. fulvoreagens (with squamatic acid) and U. wasmuthii (with psoromic acid) have been identified. Distribution maps of U. dasaeaand U. subcornuta in Europe are presented. A new combination, Usnea subfloridana subsp. praetervisa (Asahina) P. Clerc, is proposed.

A pocket calculator program to compute CMA in the genus Usnea (lichenized Ascomycetes)

A pocket calculator program to compute CMA in the genus Usnea (lichenized Ascomycetes)

Synopsis of the Genus Usnea (Lichenized Ascomycetes) in British Columbia, Canada

Synopsis of the Genus Usnea (Lichenized Ascomycetes) in British Columbia, Canada

Synopsis of the Genus Usnea (Lichenized Ascomycetes) in British Columbia, Canada

Synopsis of the Genus Usnea (Lichenized Ascomycetes) in British Columbia, Canada