bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tropical-Subtropical Ramalinae in the Ramalina Farinacea Complex
Authors: Stevens G. Nell 
Published: May 2007

AbstractFive corticolous taxa of sorediate Ramalinae which occur in the tropics and subtropics are shown to comprise the tropical component of the otherwise temperate Ramalina farinacea complex. Their morphology, anatomy, chemistry, ecology and distribution are discussed. Ramalina pacifica Asah., R. nervulosa (Müll. Arg.) des Abb., R. dumeticola Krog & Swinscow and R. luciae Mohlo et al., were investigated together with an unnamed acid-deficient taxon. Ramalina nervulosa and R. pacifica are maintained as species while the remainder are considered as varieties of these species; viz. R. nervulosa var. dumeticola (Krog & Swinscow) comb. nov., R. nervulosa var. luciae (Mohlo et al.) comb. nov., and R. pacifica var. inacida var. nov.
Sizes and Growth-Rates of Thalli of the Lichen Rhizocarpon Geographicum on the Moraines of the Glacier De Valsorey, Valais, Switzerland
Authors: Proctor M. C. F. 
Published: May 2007

AbstractMeasurements of thalli of Rhizocarpon geographicum on the recent moraines of the Glacier de Valsorey and their surroundings are considered in relation to thallus growth rates and colonization following glacial recession. Photographs taken in 1975 and 1979 show that up to c. 3.5 cm diam the relation of maximum growth-rate to thallus size is approximated by a growth curve of the kind derived by Aplin and Hill, rising asymptotically towards a constant rate of radial growth (here c. 0.5 mm year−1). Growth-rates of many individual thalli fall well below the maximum. Parameters of the fitted growth curves are used to construct curves of thallus radius against time. Taken in conjunction with the field measurements these suggest two main phases of colonization, one from about 1880 to 1910, and one from about 1930 onwards. Some general considerations relating to lichenometry and lichen growth curves are discussed.
Two Little-Known or Misunderstood Brigantiaea Species from New Zealand
Authors: Hafellner J. 
Published: May 2007

AbstractDescriptions are given of two little-known species of Brigantiaea (Lecanorales, Brigantiaeaceae) which are widely distributed in New Zealand. Brigantiaea lobulata F. J. Walker & Hafellner sp. nov. is described and the following new combinations are proposed: B. tabacodes (Zahlbr.), B. nipponica (Sato) and B. austroamericana (Räsänen), combs. nov.
Seasonal Photosynthetic Capacity Changes in Lichens: A Provisional Mechanistic Interpretation
Authors: Kershaw K. A. 
Published: May 2007

AbstractThe photosynthetic capacity changes that have previously been documented in lichens are reviewed together with the mechanisms of photosynthetic capacity change in free-living algae recently proposed by Prezelin and co-workers. Examination of seasonal capacity changes in Peltigera praetextata, P. rufescens, Cladonia rangiferina, C. stellaris, and Caloplaca trachyphylla using photosynthetic-illumination curves, provisionally establishes that synthesis of additional photosynthetic units, seasonal interruption of energy transduction, as well as enzymatic rate changes in the Calvin cycle, are all involved in these capacity changes.
Placynthium Arachnoideum, a New Lichen from Patagonia, and Notes on Other Species of the Genus in the Southern Hemisphere
Authors: Henssen Aino 
Published: May 2007

AbstractThe new species Placynthium arachnoideum Henssen is described from Patagonia. The lichen is characterized by incurved lobes retaining in part the false branching of the Scytonema phycobiont, and by two-celled, thick-walled spores with a perforated septum. Some localities in the Southern Hemisphere are given for P. asperellum, P. nigrum and P. subradiatum.
Quantification of Branch Dwelling Lichens for the Detection of Air Pollution Impact
Authors: Addison P. A. 
Published: May 2007

AbstractIn the Athabasca Oil Sands area of Alberta, a study was carried out to test a lichen community transplant technique and to determine the influence of oil sands extraction and processing emissions on lichen cover of transplanted communities. Measurement errors of a photographic technique for the determination of lichen cover were dependent upon lichen species but were not correlated to lichen cover. When lichen covers were small therefore, relative errors were very large. Changes in cover of naturally occurring lichen communities on black spruce branches were not significant over a four-year period. Lichen communities transplanted under jack pine and white spruce trees had cover changes with time not different from naturally occurring communities even over a period of years.Significant (P<0.001) cover reductions of some lichen groups occurred on transplanted branches under white spruce within 8–3 km of a pollution source. Evernia, Cetraria, and Bryoria groups were reduced whereas Hypogymnia showed no response over a 3 year measurement period. Reductions in lichen cover were greater than the demonstrated precision of the technique.
Impact of Simulated Acid Rains on Nitrogenase Activity in Peltigera Aphthosa and P. Polydactyla
Authors: Fritz-Sheridan R. P. 
Published: May 2007

AbstractTwo ubiquitous diazotrophic North American lichens, Peltigera aphthosa and P. polydaclyla, were subjected to simulated acid rain. Both lichens exhibited a 50% reduction in nitrogen fixation at pH 5, 80% reduction at pH 4 and complete inhibition at pH 2. Nitrogen fixation was zero after 20 days exposure to simulated rain at pH 3 and zero after fourdays at pH 2.
Apothecium Production in Xanthoria Parietina
Authors: Pentecost A. , Rose C. I. 
Published: May 2007

AbstractA regression equation was used to relate apothecium diameter to apothecium dry weight inXanthona parietina. This was used to estimate the contribution of apothecia to thallus weight in 80 randomly selected thalli from vertical concrete posts at Romney, Kent (mean 22–5%, range 0–87%). The energy contents of apothecia and the sterile thallus were found to be similar (17.6—18.2 KJ g−1 dry weight) and apothecium production was found to be independent of thallus aspect. The results are discussed with reference to apothecium growth rates and the allocation of resources in lichens.
Contribution to the Lichen Flora of Madeira
Authors: Arvidsson L. , Wall S. 
Published: May 2007

Abstract37 taxa are discussed, with 34 being new to Madeira. Of these, Gyalectidium filicmum Müll. Arg., Massalongia carnosa (Dickson) Körber, Physaa tnbaaoides Nyl. and Rinodina intermedia Bagl., are first records from Macaronesia. Ecology and distribution of the species are briefly outlined. Our investigation shows that the proportion of both northern temperate and tropical elements in the lichen flora of Madeira is higher than formerly known.
Artificial Re-Establishment of Lichens IV. Comparison between Natural and Synthetic Thalli of Usnea Strigosa
Authors: Ahmadjian V. , Jacobs J. B. 
Published: May 2007

AbstractSynthetic thalli of Usnea strigosa produced the same fibril morphology and secondary compounds as natural thalli. The outer cortex of synthetic lichens was covered with crystals of usnic acid and compounds related to norstictic acids. The common presence on the fibrils of lichen acids suggests that these compounds have a functional role in the symbiosis. During alcohol dehydration, crystals of usnic acid dissolved and left impressions in the mucilage around the symbionts. The impressions were valuable indicators of the position of crystals in the lichen thallus. Crystal impressions of usnic acid were common on the cortical hyphae and were seen also on the surface of algal cells. The crystal impressions were larger in the synthetic lichen than in natural thalli. Impressions of norstictic acid and related compounds were not seen.
The Nature and Origin of Campylidia in Lichenized Fungi
Authors: Sérusiaux E. 
Published: May 2007

AbstractThe campylidia hypothesis, first introduced by Müller Argoviensis (1881) and recently restored by Vězda (1983), for the erect helmet-shaped structures found on foliicolous lichens and usually known as ‘ Pyrenotrichum ’ is adopted as being the most satisfactory. In the Badimia pollilensis aggregate, campylidia are shown to derive from primordia identical to those of the apothecia. In the genus Sporopodium, algal cells are included in the conidiogenous layer and are dispersed together with conidia. This also seems to be the case in the genus Loflammia. Short descriptions are given for the most common campylidium known as ‘ Pyrenotrichum splitgerben ’ and for another not yet assignable to a peculiar genus. Loflammia denwulinii sp. nov. is described from New Guinea.
Aspicilia Excavata: A New Lichen Species From Europe
Authors: Thor G. , Timdal E. 
Published: May 2007

AbstractAspicilia excavata Thor & Timdal sp. nov. is described and reported from Austria, Finland, Norway and Sweden. It is usually sterile and mainly characterized by an indeterminate thallus composed of small, white pruinose squamules excavated from the margin by dark brown to black soralia. The species grows on calcareous rocks and mortar, mainly on steep to overhanging faces.
Nomenclatural Notes on Some Australian Cladonia Species
Authors: Archer A. W. 
Published: May 2007

AbstractAn examination of the holotype or lectotype of eight taxa, first described from Australia, in the genus Cladonia has shown that the names are, with the exception of Cladonia fruticulosa Krempelh., synonyms of previously described taxa. The taxa examined were as follows (with the correct name in parentheses); C. cariosa var. diffissa F. Wilson (C. enantia Nyl.); C. conchata Nyl. (C. pyxidata (L.)Hoffm.); C. cornucopioides var. grandis Krempelh. (C. pleurola (Flörke) Schaerer); C. deformis var. tasmanica Krempelh. (C. subdigitata Nyl.); Cenomyce firma Laurer, Cladonia firma (Laurer) Krempelh. (C. murrayi W. Martin); C. lepidula Krempelh. (C. ochrochlora Flörke); C. pergracilis Krempelh. (C. ochrochlora Florke); C. subsquamosa var. pulverulenta Vainio (C. squamosula Müll. Arg.) Homosekikaic acid is reported to occur with thamnolic acid in C. squamosula Müll. Arg.
Nectriella Santessonii, A New Lichenicolous Pyrenomycete With an Acremonium Anamorph
Authors: Lowen Rosalind , Hawksworth D. L. 
Published: May 2007

AbstractNectriella santessonii sp. nov. (Hypocreales) on Anaptychia runcinata (With.) Laundon, is introduced for a species that previously has been confused with N. tincta (Fuckel) R. Sant. The two species are distinguished by several fundamental characters. The growth of single ascospores in pure culture has proved the connection between the new species and an Acremonium anamorph.
A Simulation Study on the Effect of Flora Composition, Study Design and Index Choice on the Predictive Power of Lichen Bioindication
Authors: Herben T. , Liška J. 
Published: May 2007

AbstractThe effects of several elements of floristic structure and bioindication study design on the predictive power of the Index of Atmospheric Purity (IAP) proposed by LeBlanc & De Sloover were studied using Monte Carlo simulation. The predictive power was assessed by the correlation coefficient of the IAP value, computed under specified assumptions, and the stand position along a simulated pollution gradient. The effects of seven parameters were studied: proportion of sensitive and poleophilous species, species frequency distribution, size of total species pool, number of stands, distribution of stands along the air pollution gradient and index choice. The simulations showed that the median predictive power of such studies is affected mainly by the proportion of sensitive and poleophilous species, the number of species, and distribution of trees along the pollution gradient. The variance of the predictive power is influenced mainly by the proportion of sensitive species, frequency distribution, number of stands and distribution of stands along the pollution gradient. Recommendations for further bioindication studiesare given.
A Review of Psilolechia
Authors: Coppins B. J. , Purvis O. W. 
Published: May 2007

AbstractThe genus Psilolechia Massal. is reviewed; four species are accepted, including P. leprosa sp. nov. from copper-rich sites in north-west Europe and Greenland, and P. purpurascens sp. nov. from Tasmania. A hyphomycetous anamorph is described for P. clavulifera, and anomalous forms of P. lucida with a vicarious, Stichococcus photobiont are reported.
Choreospora Gen. Nov., A New Lichenicolous Hyphomycete from Australia
Authors: Constantinescu O. , Santesson R. 
Published: May 2007

AbstractChoreospora tibellii P. Const. & R. Sant. gen. & sp. nov., a sporodochial hyphomycete with non-septate, tetraradiate conidia is described from Australia. The fungus grows on a sterile foliicolous lichenized thallus (?Echinoplaca sp.) on leaves of Cordyline.
Nitrogen Fixation on the Tropical Volcano, La Soufrière (Guadeloupe): Nitrogen Fixation, Photosynthesis and Respiration During the Prevailing Cloud/Shroud Climate By Stereocaulon Virgatum
Authors: Fritz-Sheridan R. P. , Coxson D. S. 
Published: May 2007

AbstractStereocaulon virgatum Ach. has colonized lava flows deposited on the west flank of the volcano La Soufrière. The mean annual rate of acetylene reduction was 43·4 nmol C2H4 gdw−1 h−1 with maximum rates during the prevalent cloud/shroud meteorology of 101 and minimum rates during rare high insolation events of 0·63 nmol gdw−1 h−1. Percentage thallus moisture was the major variable controlling nitrogenase activity. During cloud/shroud conditions the upper 90% of the lichen canopy reduced 85% of the acetylene. Canopy shading reduced intra-canopy temperatures allowing the basal 10% of the canopy to fix nitrogen during insolation shocks. Basal portions of pseudopodetia exhibited reduced rates of ethylene production when exposed to canopy surface light intensities during cloud/shroud conditions. The recovery pattern of nitrogenase following desiccation during an insolation shock is presented. Rates of photosynthesis during cloud/shroud conditions were high, reaching 50% of those attained during saturating light intensities.
Caloplaca Lucifuga: A New Lichen Species From Europe
Authors: Thor G. 
Published: May 2007

AbstractCaloplaca lucifuga Thor sp. nov. is described and reported from Denmark, England, France, Germany, Italy and Sweden. It is only found sterile and is mainly characterized by its endophloedic, sorediate thallus, chemistry and habitat. In Sweden, the species is found in dense wooded pastures dominated by Quercus robur, growing on the bark of very old trunks of Quercus robur or, rarely, Tilia cordata. Outside Sweden, it is found also on Castanea sativa, Fagus sylvatica and Ulmus glabra.
Notes on the Genus Arthopyrenia in the British Isles
Authors: Coppins B. J. 
Published: May 2007

AbstractThe genus Arthopyrenia is redefined to include only corticolous lichenized or non-lichenized fungi. A key and notes are provided for the 14 species accepted for the British Isles, including three new species, A. carneobrunneola, A. ranunculospora and A. viridescens. Arthopyrenia nilescens is resurrected from synonymy, A. cinereopruinosa is confirmed as occurring in the British Isles, and A. fraxini, A. salicis and A. subcerasi are added to the British list. The following names are lectotypined: Arthopyrenia fraxini Massal. (including f. orbicularis Massal. and f. rufidula Massal.), A. salicis Massal., Verrucaria nitescens Salwey and V. subcerasi Vainio.
Biochemical Comparison of two Ecologically Distinctive Forms of Xanthoria Elegans in the Canadian High Arctic
Authors: Fahselt Dianne , Krol Marianna 
Published: May 2007

AbstractXanthoria elegans has a broad ecological amplitude, world-wide distribution and includes morphological variants which differ markedly with respect to colour, form and frequency of apothecia. Distinctive thallus forms are associated with different habitats. Samples from two contrasting habitats were studied on Ellesmere Island in the Canadian High Arctic. Carotenoids, polyphenolic products and isoenzymes were examined to establish whether two thallus types were biochemically distinct. Pigments were comparable in both morphological variants, as were approximately half of the most frequently occurring enzyme forms. Enzymatic similarity between the two resembled that between conspecific populations of other lichens. On the basis of the chemical attributes investigated, the thallus forms did not warrant recognition as fundamentally distinct entities, but were merely variants of an ecologically versatile and extremely plastic species.
Notes on the Arthoniaceae in the British Isles
Authors: Coppins B. J. 
Published: May 2007

AbstractArthonia anglica Coppins, A. anombrophila Coppins & P. James (syn. A. cinereopruinosa auct. brit.) and A. ligniariella Coppins are newly described, and Arthothelium ilicinum var. dictyosporum is given specific rank. British material of ‘Arthonia exilis’ is shown to be Bryostigma leucodontis Poelt & Döbb., which is transferred to Arthonia. Arthonia granitophila Th. Fr. (syn. Melaspilea subarenacea J. Nowak & Kiszka) is transferred to Melaspilea. Arthonia ligniaria Hellb. is added to the British list. Arthonia astroidestra Nyl. is lectotypified and shown not to be conspecific with A. stellaris Krempelh., while A. excipienda Nyl. (syn. A. hibernica Nyl.) is found not to be a synonym of A. dispersa (Schrader) Nyl. Catillaria ooliticola W. Watson is made a synonym of A. lapidicola (Taylor) Branth & Rostrup; Arthonia punctilliformis Leighton is excluded from that genus; and A. dispersa and A. patellulata Nyl. are excluded from the British list. In addition, four new lichenicolous species on corticolous hosts are introduced: Arthonia cohabitans Coppins, A. graphidicola Coppins, A. invadens Coppins and A. thelotrematis Coppins.
Macentina Stigonemoides (Verrucariaceae), a New Lichenized Species from Great Britain and Ireland
Authors: Orange A. 
Published: May 2007

AbstractMacentina stigonemoides sp. nov. is described from trees in Great Britain and Ireland; it is characterized by a filamentous to granular thallus with papillose cortical cells and pale perithecia with 3–5-septate spores.
The Genus Bryoria Sect. Implexae in Norway
Authors: Holien H. 
Published: May 2007

AbstractIn Norway three species are recognized in the genus Bryoria sect. Implexae, B. capillaris (Ach.) Brodo & D. Hawksw., B. implexa (Hoffm.) Brodo & D. Hawksw., and B. nadvornikiana (Gyeln.) Brodo & D. Hawksw. Notes on their morphology, chemistry, ecology and distribution are given. Bryoria friabilis Brodo & D. Hawksw., B. pseudofuscescens (Gyeln.) Brodo & D. Hawksw., and B. vrangiana (Gyeln.) Brodo & D. Hawksw. are considered to be conspecific with B. implexa. Bryoria setacea (Ach.) Brodo & D. Hawksw. is considered to be conspecific with B. capillaris.
Enzyme Polymorphism in Sexual and Asexual Umbilicate Lichens from Sverdrup Pass, Ellesmere Island, Canada
Authors: Fahselt Dianne 
Published: May 2007

AbstractFour enzymes were examined electrophoretically from each of seven stands of arctic umbilicate lichens in central Ellesmere Island. The species studied included Umbilicaria virginis Schaerer, which was prolifically apotheciate, and U. decussata (Vill.) Zahlbr. and U. hyperborea (Ach.) Hoffm., which were both sterile. Electrophoretic banding patterns were converted to presence/absence data reflecting the occurrence of electromorphs in each thallus, and enzyme polymorphism was assessed using three statistical methods, one based on frequency of individual enzyme forms, another on the number of banding patterns, and a third on the proportional representation of different band patterns within each collection site. Greater enzyme variability occurred in stands of apotheciate species than in stands of species which were asexual in the study area, suggesting that regular sexual reproduction contributes to greater diversity.
The Lichen Genus Pterygiopsis in Northern Europe
Authors: Jørgensen P. M. 
Published: May 2007

AbstractThe genus Pterygiopsis Vainio (Lichinaceae), originally described from Brazil, is shown to have two species in Northern Europe: P. coracodiza (Nyl.) Henssen growing on irrigated rocks in N.W. Europe (France, Great Britain, W. Sweden and Norway), and P. lacustris P. M. Jørg. & R. Sant. sp. nov. occurring ± submerged in some lakes in S. Sweden.
Studies on Micarea in Australasia I. Four New Species From Tasmania
Authors: Coppins B. J. , Kantvilas G. 
Published: May 2007

AbstractFour new species of Micarea are described from Tasmanian collections: M. austroternaria sp. nov. (also from Chile), M. flagellispora sp. nov. (also from New Zealand), M. isabellina sp. nov., and M. mutabilis sp. nov. (also from mainland Australia).
Isidiate Taxa in the Teloschistales and their Ecological and Evolutionary Significance
Authors: Kärnefelt I. 
Published: May 2007

AbstractThirteen isidiate taxa in the Teloschistales are briefly discussed, i.e. Letrouitia corallina (Müll. Arg.) Hafellner, L. leprolyta (Nyl.) Hafellner, Caloplaca bassiae (Ach.) Zahlbr., C. granulosa (Müll. Arg.) Jatta, C. herbidella (Hue) H. Magn., C. isidiigera Vězda, C. isidiosa (Vainio) Zahlbr., C. littorea Tavares, C. namibensis Kärnef., C. ochraceofulva (Müll. Arg.) Jatta, C. verruculifera (Vainio) Zahlbr., Xanthoria domogledensis Veˇzda and X. isidioidea (Beltr.) Szat. The presumed origins and affinities of these taxa, which are also often fertile, are discussed. The role of isidia in reproduction and dispersal, and the justification of specific status in some of these taxa is questioned.
Decomposition of Species of Pseudocyphellaria and Sticta in a Southern Chilean Forest
Authors: Guzman G. , Quilhot W. , Galloway D. J. 
Published: May 2007

AbstractThe annual rate of lichen decomposition was measured in a mixed, cool temperate rainforest in Puyehue National Park, southern Chile. Five macrolichens, Pseudocyphellaria berberina, P. divutsa, P. glabra, P. nitida and Sticta hypochra, and bamboo leaves (Chusquaea macrostachya) were used as experimental material. Rates of decomposition are high in all lichen species and ranged from k = 0·45 to 2·79. Lichens with hopane triterpenoids {P. divulsa and P. glabra) were more resistant to decomposition. The contribution of these lichens to the nutrient economy of the rainforest ecosystem is highly significant, as they are both abundant in terms of biomass and have a rapid turnover.
Lichens of the Dartmoor Rocks
Authors: Giavarini V. J. 
Published: May 2007

AbstractA description of the lichen communities associated with natural rock outcrops and derelict mine workings in the upland region of Dartmoor, south-west England, is presented. An examination of 34 study sites revealed 270 taxa, of which 28 are reported as new to Devon including several national rarities. Notes on 29 tors have been prepared and reasons for the predominance or decline of particular communities or species are discussed.