Vulpicida Pinastri Research Articles

Biodiversity-Based Empirical Critical Loads of Nitrogen Deposition in the Athabasca Oil Sands Region

Anthropogenic nitrogen (N) emissions can have considerable effects on terrestrial ecosystems, with chronic N deposition leading to changes in plant species composition. The Athabasca Oil Sands Region (AOSR) represents a large point source of N emissions, which has prompted concern for surrounding habitats. The objective of this study was to determine the relative importance of N deposition as a driver of plant species community composition against bioclimatic and soil chemical variables. Further, we sought to identify community thresholds in plant species composition across a N deposition gradient. This assessment was performed for 46 Jack pine (Pinus banksiana Lamb.)-dominant forest sites surrounding the AOSR spanning Alberta and Saskatchewan. In total, 35 environmental variables were evaluated using redundancy analysis (RDA), followed by gradient forest analysis applied to plant species abundance data. Soil chemical variables accounted for just over 26% of the total explainable variation in the dataset, followed by bioclimatic variables (19%) and deposition variables (5%), but joint effects between variables also explained a significant portion of the total variation (p < 0.001). Total deposited nitrogen (TDN), and sulphur (TDS) along with bioclimatic and soil chemical variables, were identified as important variables in gradient forest analysis. A single, definitive threshold across TDN was identified at approximately 5.6 kg N ha−1 yr−1 (while a TDS threshold was found at 14.4 kg S ha−1 yr−1). The TDN threshold range was associated primarily with changepoints for several vascular species (Pyrola asarifolia, Pyrola chlorantha, Cornus canadensis, and Arctostaphylos uva-ursi) and bryophyte and lichen species (Pleurozium schreberi, Vulpicida pinastri, and Dicranum polysetum). These results suggest that across Jack pine-dominant forests surrounding the AOSR, the biodiversity-based empirical critical load of nutrient N is 5.6 kg N ha−1 yr−1.

Ecological Risks from Atmospheric Deposition of Nitrogen and Sulphur in Jack Pine forests of Northwestern Canada

Chronic elevated nitrogen (N) deposition can have adverse effects on terrestrial ecosystems. For large areas of northern Canada distant from emissions sources, long-range atmospheric transport of N may impact plant species diversity, even at low deposition levels. The objective of this study was to establish plant species community thresholds for N deposition under multiple environmental gradients using gradient forest analysis. Plant species abundance data for 297 Jack pine (Pinus banksiana Lamb.)-dominant forest plots across Alberta and Saskatchewan, Canada, were evaluated against 43 bioclimatic and deposition variables. Bioclimatic variables were overwhelmingly the most important drivers of community thresholds. Nonetheless, dry N oxide (DNO) and dry N dioxide deposition inferred a total deposited N (TDN) community threshold of 1.4–2.1 kg N ha−1 yr−1. This range was predominantly associated with changes in several lichen species, including Cladina mitis, Vulpicida pinastri, Evernia mesomorpha and Lecanora circumborealis, some of which are known bioindicators of N deposition. A secondary DNO threshold appeared to be driving changes in several vascular species and was equivalent to 2.45–3.15 kg N ha−1 yr−1 on the TDN gradient. These results suggest that in low deposition ‘background’ regions a biodiversity-based empirical critical load of 1.4–3.15 kg N ha−1 yr−1 will protect lichen communities and other N-sensitive species in Jack pine forests across Northwestern Canada. Nitrogen deposition above the critical load may lead to adverse effects on plant species biodiversity within these forests.

Lichen Extracts from Cetrarioid Clade Provide Neuroprotection against Hydrogen Peroxide-Induced Oxidative Stress.

Oxidative stress is involved in the pathophysiology of many neurodegenerative diseases. Lichens have antioxidant properties attributed to their own secondary metabolites with phenol groups. Very few studies delve into the protective capacity of lichens based on their antioxidant properties and their action mechanism. The present study evaluates the neuroprotective role of Dactylina arctica, Nephromopsis stracheyi, Tuckermannopsis americana and Vulpicida pinastri methanol extracts in a hydrogen peroxide (H2O2) oxidative stress model in neuroblastoma cell line “SH-SY5Y cells”. Cells were pretreated with different concentrations of lichen extracts (24 h) before H2O2 (250 µM, 1 h). Our results showed that D. arctica (10 µg/mL), N. stracheyi (25 µg/mL), T. americana (50 µg/mL) and V. pinastri (5 µg/mL) prevented cell death and morphological changes. Moreover, these lichens significantly inhibited reactive oxygen species (ROS) production and lipid peroxidation and increased superoxide dismutase (SOD) and catalase (CAT) activities and glutathione (GSH) levels. Furthermore, they attenuated mitochondrial membrane potential decline and calcium homeostasis disruption. Finally, high-performance liquid chromatography (HPLC) analysis revealed that the secondary metabolites were gyrophoric acid and lecanoric acid in D. artica, usnic acid, pinastric acid and vulpinic acid in V. pinastri, and alectoronic acid in T. americana. In conclusion, D. arctica and V. pinastri are the most promising lichens to prevent and to treat oxidative stress-related neurodegenerative diseases.

Phytochemical Characterization and Pharmacological Properties of Lichen Extracts from Cetrarioid Clade by Multivariate Analysis and Molecular Docking.

Introduction Lichens, due to the presence of own secondary metabolites such as depsidones and depsides, became a promising source of health-promoting organisms with pharmacological activities. However, lichens and their active compounds have been much less studied. Therefore, the present study aims to evaluate for the first time the antioxidant capacity and enzyme inhibitory activities of 14 lichen extracts belonging to cetrarioid clade in order to identify new natural products with potential pharmacological activity. Materials and Methods In this study, an integrated strategy was applied combining multivariate statistical analysis (principal component analysis and hierarchical cluster analysis), phytochemical identification, activity evaluation (in vitro battery of antioxidant assays FRAP, DPPH, and ORAC), and enzyme inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) and molecular profiling with in silico docking studies of the most promising secondary metabolites. Results. Among fourteen lichen samples, Dactylina arctica stands out for its higher antioxidant capacities, followed by Nephromopsis stracheyi, Tuckermannopsis americana, Vulpicida pinastri, and Asahinea scholanderi. Moreover, Asahinea scholanderi and Cetraria cucullata extracts were the best inhibitors of AChE and BuChE. The major secondary metabolites identified by HPLC were alectoronic acid and α-collatolic acid for Asahinea scholanderi and usnic acid and protolichesterinic acid for Cetraria cucullata. Molecular docking studies revealed that alectoronic acid exhibited the strongest binding affinity with both AChE and BuChE with and without water molecules. Conclusions Our results concluded that these species could be effective in the treatment of neurodegenerative diseases, being mandatory further investigation in cell culture and in vivo models.

LICHENS AND LICHENICOLOUS FUNGI OF NATIONAL NATURE PARKS «NYZHNOSULSKY» AND «PYRYATYNSKY»

Introduction. Currently, the protected areas of the Poltava region remain poorly understood. Purpose. This is a comprehensive study of the lichens and lichenicolous fungi on the territory of two National Nature Parks (NNPs). Methods. Collecting was carried out by the route­expedition method. Lichens and lichenicolous fungi were identifid in accordance with a standard procedure. Results. NNP «Nyzhnyo sulsky» was represented by 54 species of the lichens and 6 species of the lichenico lous fungi. 55 species of the lichens and 4 species of the lichenicolous fungi were found on the territory of the NNP «Pyryatynsky». Corticolous lichens are dominant ecological groups in both National Nature Parks. 50 corticolous species (92 %) were found in NNP «Nyzhnyosulsky» and 46 species (82 %) were found in NNP «Pyryatynsky». These species are confied to the growth on the bark of the hardwood trees, especially Betula, Populus, Robinia and Quercus. The mature oaks are the most valuable lichen habitat in the parks. Such species as Arthonia mediella, Bacidia rubella, Caloplaca obscurella, Candelariella faginea, Chaenotheca trichialis, Dimerella pineti, Graphis scripta, Pachyphiale carneola have been found rarely on the oak bark on the plain part of Ukraine. Among them A.mediella, C. obscurella and D. pineti are first time reported for the Left­Bank Forest­Steppe zone of Ukraine. The bark of Populus nigra is a habitat for a few rare species, such as Arthrosporum populorum, Lecania fuscella, Piccolia ochrophora and Rinodina pityrea. Rare species in Ukrainian plain A. cinereopruinosa, Buellia griseovirens, Lecanora symmicta, Parmeliopsis ambigua, Trapeliosis granulosa, Vulpicida pinastri were found on the bark of Betula verru cosa in NNP «Pyryatynsky». A. cinereopruinosa is a new one for Left Bank ForestSteppe zone. Seven species of lichens (A. populorum, B. griseovirens, P. argena, P. ochrophora, R. pityrea, T. granulosa, X. candelaria) and three species of li chenicolous fungi (Athelia arachnoidea, Erythricium aurantiacum, Xanthoriicola physciae) are first time reported for the Poltava region. Terricolous lichens such as Bacidia bagliettoana, Diploschistes muscorum, Mycobilimbia subulatorum and Peltigera didactуla are usually associated with weakly overgrown slopes of the ravines and beams. Terricolous lichens B. bagliettoana and P. didactyla are vulnerable in lowland landscapes of Ukraine and need to be protected at the local level. Lichenicolous fungi Pronectria diplococca on En chylium tenax and Homostegia piggotii on Parmelia sulcata are new for Left Bank Forest Steppe zone. Conclusion. Thus, the species diversity of lichens of both NPPs is typical of the forest steppe zone and needs to be protected.

Preliminary results of spectrophotometric screening of secondary metabolites accumulation in lichen thalloms

This paper discusses the influence of biotopic conditions on the secondary compounds accumulation in lichen thalloms. Secondary metabolites inherent in the metabolism of various groups of organisms are widely represented in symbiotic organisms lichens, with a significant number of these compounds being phenolic derivatives. The authors of the paper present the results of spectrophotometric scanning of alcohol extracts from lichen thalloms of three species: Xanthoria parietina (L.) Belt., Parmelia sulcata Tayl., Vulpicida pinastri (Scop.) J.-E. Mattsson M.J. Lai, sampled in different forest communities of the Krasnosamarsky forest (Samara Region), in 9 plots, where plant communities were fragments of natural forests (birch, aspen, linden, oak) and forest stands. Forest communities differed in their position in the relief, the composition of the arboreal stage, associated with the height and closeness of the plantations to microclimate conditions. The extracts obtained by infusion of 96% ethanol samples were analyzed using the AZURA UV / VIS UVD 2.1 L detector (190750 nm, Knauer) in the laboratory of Chemistry Department of Samara University to obtain absorption spectra in the UV region using the ClarityChrom program. The study can be considered as an initial stage of bioecological screening, which makes it possible to ascertain the dependence of the secondary metabolites accumulation on habitat parameters in relation to the conditions of forest ecosystems in different parts of the Samara Region. The spectrophotometric study of the extracts demonstrated the presence of species-specific features of the spectra, indicating the differences in the qualitative composition of the extracts. For extracts obtained from samples of lichens were found spectra differences: quantitative for all the species, and also qualitative for Xanthoria parietina and Vulpicida pinastri extracts, related to qualitative and quantitative differences in the accumulation of secondary metabolites. These differences are presumably associated with differences in the biotopic conditions of growth of the thalli of the three studied lichen species.

Specialized Metabolites of the Lichen Vulpicida pinastri Act as Photoprotective Agents.

The extreme resiliency of lichens to UV radiations makes them an interesting model to find new photoprotective agents acting as UV-blockers and antioxidant. In this research, using a new in vitro method designed to overcome the shortage of material associated to many studies dealing with natural products, we show that the three major compounds isolated from the lichen Vulpicida pinastri, vulpinic acid, pinastric acid and usnic acid, were UV blocker agents. Antioxidant assays evidenced superoxide anion scavenging activity. Combination of the most promising compounds against UVB and UVB radiations, usnic acid, vulpinic acid and pinastric acid, increased the photoprotective activity. At the same time, they were found not cytotoxic on keratinocyte cell lines and photostable in the UVA and UVB ranges. Thus, lichens represent an attractive source to find good candidate ingredients as photoprotective agents. Additionally, the uncommon scalemic usnic acid mixture in this Vulpicida species was proven through electronic circular dichroism calculation.

LICHENS AND LICHENICOLOUS FUNGI OF RESERVED TRACTS "NEDOHIRSKYY FOREST" (VELYKOOLEKSANDRIVKA DISTRICT, KHERSON REGION, UKRAINE)

The inventory results of the lichen biota of the reserved tracts "Nedohirskyy forest" (Velykooleksandrivka district, Kherson region) are given. Lichens were collected on the territory of tracts "Nedohirskyy forest" during expeditions in 2012-2015 by the standard method. The identification of species was carried out in the laboratory of biodiversity and ecological monitoring of Kherson State University. Collection of lichens is stored in the lichenological herbarium of Kherson State University (KHER). The lichen biota of reserved tracts "Nedohirskyy forest" constitutes 49 species of lichens and 4 species of lichenicolous fungi belonging to 18 genera, 8 families, 2 orders. Five species Anaptychia ciliaris (L.) Koerb. Ex A. Massal., Bryoria implexa (Hoffm.) Brodo & D. Hawksw., Endocarpon pusillum Hedw., Peltigera didactula (With.) JR Laundon, Usnea hirta (L.) Weber ex FH Wigg. are included in the Red List of Kherson region. Species Catillaria nigroclavata is new for the steppe zone of Ukraine. Buellia griseovirens (Turner & Borrer ex Sm.) Almb., Catillaria nigroclavata (Nyl.) J. Steiner, Vulpicida pinastri (Scop.) J.–E. Mattsson are rare for the steppe zone of Ukraine and need to be included into the Red List of Kherson region.

Forest-structure data improve distribution models of threatened habitat specialists: Implications for conservation of epiphytic lichens in forest landscapes

Epiphytic lichens are an important component of forest biodiversity. Many of them are threatened and conservation planning therefore requires comprehensive information about their distribution over space and time. However, besides topo-climatic predictors, the spatial pattern of epiphytic lichens is also closely related to the tree characteristics on which they grow. In this paper, we tested the hypothesis that habitat specialist lichens restricted to specific habitat types and common species with a wide range of ecological preferences may respond differently to the topo-climatic and forest-structure predictors. We applied the generalized linear model (GLM) and maximum entropy (Maxent) for 20 epiphytic lichen species in Switzerland at different spatial scales (1km and 100m). To evaluate the influence of forest structure on the epiphytic lichen distribution, models with three sets of predictors (topo-climatic, forest-structure and combined predictor sets) were fitted for each species. Canopy height of forest stands and forest type were tested as a proxy of forest structure. Our results showed that both the techniques applied predicted well the occurrences of habitat specialists but the models of common lichens were overall less accurate. Forest-structure predictors significantly improved the models of rare and threatened species with specific microhabitat requirements, i.e. mainly forest lichens (Arthonia byssacea, Bactrospora dryina, Calicium viride, Gyalecta truncigena and Vulpicida pinastri), but they did not contribute considerably to the models of common species that grow equally well on the bark of different trees within or outside of forests (e.g. Caloplaca cerina, Phaeophyscia orbicularis, Physcia stellaris and Xanthoria parietina). We recommend using high-resolution forest-structure data for robust and reliable predictions of the distribution patterns of threatened epiphytic lichens, most of which are habitat specialists. The inclusion of these data will allow a hypothesis-driven sampling strategy, and will thus increase the effectiveness of the field sampling needed for searching large regions thoroughly to discover new sites where rare and threatened species occur.

Vertical distribution of macrolichens on the birches near Petropavlovsk-Kamchatskii

Species composition and frequency of occurrence of macrolichens on Betula ermanii and B. platyphylla are studied. Frequency of occurrence of most species of these lichens is less than 10%. Frequency of occurrence of some species on different trunk levels was considerably different. Usually, frequency of occurrence of macrolichens on B. ermanii was higher than on B. platyphylla. Distribution of ten dominant species on different trunk height was studied applying one-factored ANOVA. Cladonia coniocraea, Parmelopsis sp., and Vulpicida pinastri occur preferably on trunk bottoms. Cetraria sepincola was homogeneously on trunks of both birch species. Hypogymnia physodes, Parmelia squarrosa, and P. sulcata are definitely confined to the middle part of trunks and branches only on B. ermanii. On B. platyphylla, these species are homogeneously distributed.

Testing morphology-based delimitation of Vulpicida juniperinus and V. tubulosus (Parmeliaceae) using three molecular markers

AbstractThe delimitation of two morphologically similar and not easily separable Vulpicida species, V. juniperinus and V. tubulosus, is analyzed using nuclear ITS and Mcm7, and mitochondrial SSU DNA sequences. Seventy-nine Vulpicida specimens, most from the two focal taxa, are included in the three-locus gene tree. The results from Bayesian and parsimony analyses are presented. There are strong conflicts between the single locus gene trees. Vulpicida juniperinus and V. tubulosus are divided into two clearly distinguished groups in the ITS and concatenated B/MCMC tree. However, these species are mixed in both clades, appearing polyphyletic. Currently accepted V. juniperinus and V. tubulosus are not distinct according to the loci studied. Vulpicida pinastri appears monophyletic based on the available sequences.

Note on Cladonia species (lichenized Ascomycota) from Ardahan province (Turkey)

This paper is the first report on <em>Cladonia </em>species from Ardahan, a north-eastern province of Turkey. A circumpolar boreal-low arctic species, <em>Cladonia acuminata</em>, rarely reported from Asia, and the recently described <em>Cladonia monomorpha </em>are reported as new for Turkey. Their detailed descriptions and taxonomical remarks are provided. Localities of other ascertained <em>Cladonia </em>species in the province supplement the knowledge of their distribution patterns in the country. In addition, the typically corticolous/lignicolous species <em>Vulpicida pinastri </em>is mentioned as also growing on primary squamules and podetia of <em>C. pyxidata</em>.

Changes in the distributions of epiphytic lichens in southern Sweden using a new statistical method

Past studies on changes in species distribution have mainly been based on analysis of range boundaries. In contrast, the method used here evaluates shifts in species’ geographic centroids within a predefined area. We used presence/absence data on epiphytic lichens collected 1986 and 2003 from 64 sites in southern Sweden. A centroid was calculated each year, for each lichen species and substrate. The distance of centroid movement was evaluated in a permutation procedure. In total, 56 lichen species on 22 tree species were involved in the analyses, yielding 30 cases that had sufficient sample sizes both years to be evaluated. Out of these, three exhibited a significant movement of their centroid. The shift of lichen centroids of Hypogymnia physodes (L.) Nyl. and Vulpicida pinastri (Scop.) J.‐E. Mattsson & M. J. Lai on the tree species Juniperus communis L. was 50 and 151 km with the direction 27° and 48°, respectively. For Hypogymnia physodes on Pinus sylvestris L., corresponding values were 41 km and 30°. The northnortheast shifts of these species in Sweden could be a response to a warming climate.

Epiphytic lichens indicate recent increase in air pollution in the Mongolian capital Ulan Bator

Mongolia is one of the least densely populated countries of the world with 2·6 million people occupying an area of 1·5 million km2. A high proportion of the population and economy is concentrated in the capital Ulan Bator, which has 1 million inhabitants. Ulan Bator is characterized by its high elevation (1350 m), low precipitation (300 mm), high annual sunshine duration, and its location in a basin. The city is surrounded by mountain ranges to the north and to the south. Furthermore, it is the coldest capital of the world with an annual mean temperature of −3·7°C (Hilbig et al. 2004). Outside Ulan Bator and a few industrial areas, including a large copper plant near the second-largest city Erdenet, Mongolia’s air is extremely pure (ADB 2006). Therefore, Mongolia’s forests, which cover 10% of the country (Erdenechuluun 2006) harbour a rich epiphytic lichen vegetation (Cogt 1995). Most of these woodlands are conifer stands that form the southernmost range of the continuous Siberian taiga forests (Gunin et al. 1999). Eighty percent of the forest area of Mongolia is covered by Larix sibirica (Savin et al. 1978), while other important tree species in the taiga include Pinus sibirica, P. sylvestris, Picea obovata, Abies sibirica, and Betula platyphylla (Hilbig 1995; Dulamsuren et al. 2005). Dominant epiphytic lichen species in the larch-dominated taiga include Bryoria fuscescens, B. nadvornikiana, Evernia mesomorpha, Flavopunctelia soredica, Hypogymnia bitteri, H. physodes, Lecanora symmicta, Melanohalea septentrionalis, Parmelia sulcata, Usnea sp., and Vulpicida pinastri (Biazrov 1974; Hauck et al. 2007).

Conservation of the rare British lichen Vulpicida pinastri: changing climate, habitat loss and strategies for mitigation

Abstract:Autecological information targeted towards rare and threatened lichen species is severely lacking. This study adopts the rare British lichen Vulpicida pinastri as a case study species and examines its ecological response to emerging threats: climate change and the recurrent loss of its primary habitat (juniper scrub). We used predictive niche modelling to examine the response of V. pinastri to a range of present-day climatic variables. A successful model was projected for a period during the 2050s based on IPCC climate change scenarios (UKCIP02 data), and threat was estimated as the proportional change in bioclimatic space. To estimate the potential range now and during the 2050s, projected bioclimatic space was masked by a habitat map equivalent to (i) the present-day distribution of juniper and (ii) theoretical juniper distribution based on existing rates of decline. Our results point to potential range loss of V. pinastri with climate warming, exacerbated by the recurrent decline in juniper habitat. This predictive modelling approach was complemented by an assessment of local stand-scale effects. At four sites in north-east Scotland we examined the occurrence and abundance of V. pinastri thalli, in response to juniper spatial distribution, and the life-stage and structure of individual shrubs. Vulpicida pinastri appeared to be dispersal limited at small-scales, and was significantly more abundant on old and degenerate juniper shrubs. Our results evidence a close relationship between management for habitat quality and effective lichen conservation. Effective conservation of V. pinastri must ensure cohorts of older and degenerate juniper shrubs are maintained at sites where the species is expected to be most resistant to long-term climate warming, i.e. in the uplands of north-east Scotland.

Lichens of the Boreal Forests of Labrador, Canada: A Checklist

A total of 51 lichens are reported for the boreal forest of Labrador, Canada. Alectoria sarmentosa, Bryoria furcellata, Plastimatia glauca, Ramalina dilacerata, Usnea filipendula and Vulpicida pinastri appear to be new to the lichen checklist for Newfoundland and Labrador (2007) and were found growing on stands of Black spruce (Picea mariana) near Winnikapau Lake in the Churchill River Basin, Labrador, north-eastern Canada (53°15.578' N, 62°36.886' W). Small cushions of Cladonia labradorica were also found near Winnikapau Lake on exposed glacio-fluvial sand blow-outs. This study makes further steps towards updating the inventory of lichen communities in the boreal forests along the Churchill River, Labrador.

Interspecific interactions of wood-decomposing fungi with epiphytic lichens and mosses

(Ach.) Schaerer, Cl. coniocraea (Florke) Spreng., Cl. fimbriata (L.) Fr., Evernia mesomorpha Nyl., Mycoblastus sanguinarius (L.) Norman, Hypogymnia physodes (L.) Nyl., Parmelia sulcata Tayl., Platismatia glauca (L.) W. Culb. et C. Culb., Usnea spp., and Vulpicida pinastri (Scop.) J.-E. Mattson et M.J. Lai. For mosses, the total frequency of contact between gametophytes and fungal fruiting bodies was estimated. In each test area, 100 units of substrate with fruiting bodies of F. fomentarius and 50 units of substrate with fruiting bodies of F. pinicola were examined. The analysis of occurrence of fruiting bodies on substrates with different degrees of decomposition showed that F. fomentarius and F. pinicola formed fruiting bodies mainly on wood of the second and third degrees of decomposition (figure). Up to 97% of F. fomentarius fruiting bodies and 99% of F. pinicola fruiting bodies were formed on substrates with less than 20% lichen coverage, and up to 84% of fruiting bodies of both species were found on wood substrates where lichens occupied only 1‐5%. On tree trunks with fruiting bodies, moss coverage was also low: 73‐83% of F. fomentarius and 64‐90% of F. pinicola fruiting bodies were on substrates with no more than 5% of the total area occupied by mosses. Only in the Basegi Reserve did 60% of substrates with

UV triggers the synthesis of the widely distributed secondary lichen compound usnic acid

Synthesis of the cortical dibenzofuran derivative usnic acid and the medullary depsidone salazinic acid was studied in Xanthoparmelia stenophylla thalli from which the compounds had been removed by acetone rinsing prior to a 21-day field experiment with UV absorbing and transmitting screens. Natural levels of ultraviolet radiation clearly induced the re-synthesis of usnic acid. The re-synthesis was boosted by the addition of ribitol, the carbohydrate delivered from the Trebouxia photobiont to the mycobiont. Salazinic acid was also weakly induced by UV. Re-synthesis was relatively low, up to 2.5 and 3.1% of start values for usnic and salazinic acid, respectively. However, given that the natural content of both compounds was high, constituting 12% of thallus dry weight, the absolute amounts of lichen compounds re-synthesised were not so small. We also studied the extractability of nine extracellular lichen compounds in three species X. stenophylla, Hypogymnia tubulosa, and Vulpicida pinastri, and found two distinct fractions of cortical compounds, one major that was completely extractable from living lichens and one minor that was only extractable with grinding. Medullary compounds were completely extracted without grinding. These findings did not influence the relative differences between treatments in our experiment, but may be of importance for future assessments of, e.g., quantitative studies of extracellular lichen compounds.

Rapid changes in the epiphytic macrolichen flora on sites in southern Sweden

A relatively quick and simple method is presented for monitoring changes in distribution and in site and substratum preferences of epiphytic macrolichens; the method also records the natural turnover of common species. Changes in the epiphytic lichen flora in southern Sweden were recorded at 64 sites in 1986 and again in 2003. In total 1990 observations of lichens were recorded on 15 tree species, mainly on trunks but also on branches up to 2 m above the ground. Almost all species showed a high turnover with regard to substratum, including very abundant species such as Hypogymnia physodes. Many of the species had changed substratum within their sites, possibly reflecting a general change in the ecological quality of sites. Canonical Correspondence Analysis was used to extract the variation in species composition over time, using 1685 records of 55 lichen species on 8 different substrata. Some species such as Hypogymnia tubulosa had increased in abundance whilst others such as Vulpicida pinastri had decreased.

Host preference and performance of lichenivorous Eilema spp. larvae in relation to lichen secondary metabolites

Summary We compared the larval host preference of four lichenivorous Eilema (Lepidoptera, Arctiidae) species on four common epiphytic lichen species including Hypogymnia physodes, Melanelia exasperata, Vulpicida pinastri and Xanthoria parietina. Survival and growth of larvae on different species were monitored and correlation to qualitative and quantitative variation in lichen secondary compounds was analysed. All moth species preferred M. exasperata, which does not contain polyphenolic substances, over other lichens, but also foraged on other lichens in the food preference experiment. All larvae reared on V. pinastri and H. physodes died during the growth and survival experiment. Survival of larvae on X. parietina and M. exasperata were equal. Larvae grew faster and and bigger on M. exasperata than on other lichens. Consumption and utilization measurements also revealed that M. exasperata was of the highest quality, although the relative consumption rate was highest on X. parietina. Our results indicate that different secondary chemicals have different effect against lichenivores or that larvae are either well adapted to certain chemicals or that these chemicals may have other roles than antiherbivore function for lichens. It is suggested that lichenivorous lepidopteran species may have different adaptations, such as dietary mixing to receive nutrients in optimal proportions or compensatory feeding ability to ensure the maximal growth efficiency on a suboptimal host.