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Christian Printzen - One of the best experts on this subject based on the ideXlab platform.
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Testing the correlation between norstictic acid content and species evolution in the Cetraria aculeata group in Europe
The Lichenologist, 2017Co-Authors: Tetiana Lutsak, Fernando Fernández-mendoza, Olga Nadyeina, Ayhan Şenkardeşler, Christian PrintzenAbstract:AbstractMost lichen-forming fungi are characterized by the production of secondary metabolites. Differences in metabolite patterns have frequently served to distinguish lichen taxa with subsequent controversies about the rank of chemical variants (chemotype, variety, subspecies or species). Using a model system, we investigate whether production of norstictic acid within a group of lichenized ascomycetes is correlated with phylogenetic patterns, population differentiation or single and multi-locus haplotypes. Our study is based on DNA sequences of three gene loci (ITS, GPD, mtLSU) together with HPLC (311) and TLC (594) data from a total of 594 samples of three closely related fruticose lichens: Cetraria aculeata and C. muricata without norstictic acid, and C. steppae with norstictic acid. In nature, C. aculeata and C. steppae often occur together and the status of C. steppae as a separate species has been questioned. Our results show geographical but no phylogenetic structure of norstictic acid production and few significant associations between genetic clusters and the occurrence of norstictic acid. All frequently distributed haplotypes display differences in norstictic acid content. The few associations at the population level are most likely a by-product of spatial genetic structure, because norstictic acid was expressed only in individuals from the Mediterranean-Central Asian part of the study area. We conclude that the production of norstictic acid in the C. aculeata group is most likely triggered by the environment (climate, edaphic factors, associated symbionts). Cetraria steppae might be a different evolutionary lineage restricted to warm temperate regions but it is not uniquely characterized by the presence of norstictic acid.
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Mycobiont-photobiont interactions of the lichen Cetraria aculeata in high alpine regions of East Africa and South America
Symbiosis, 2016Co-Authors: Tetiana Lutsak, Fernando Fernández-mendoza, Paul Kirika, Melaku Wondafrash, Christian PrintzenAbstract:Lichens represent an extremely successful symbiosis between fungi and photosynthetic partners. It has been suggested that lichens can enhance their adaptive potential and widen their ecological niches by associating with locally adapted photobionts. Based on a worldwide population sample of the lichen Cetraria aculeata we investigate the genetic diversity and composition of photobiont and mycobiont populations of this species with a special focus on tropical alpine regions that have never been studied before. Probably due to their geographic isolation and founder effects during colonization, tropical mycobiont populations display low genetical diversity. In sharp contrast, tropical photobiont populations are among the most diverse within the species and similar in composition to polar populations. These results support the hypothesis of photobiont switching as an adaptive strategy in lichens.
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Biogeography and ecology of Cetraria aculeata, a widely distributed lichen with a bipolar distribution
MycoKeys, 2013Co-Authors: Christian Printzen, Fernando Fernández-mendoza, Stephanie Domaschke, Sergiо Pérez-ortegaAbstract:Ecological and historical biogeography of lichens have rarely been studied in a concerted effort, but both aspects have to be taken into consideration when explaining the distributional patterns of species. This review summarizes, partly preliminary, results from a series of studies on phylogeography, ecophysiology and symbiotic interactions of the lichen Cetraria aculeata. This species is not only widespread but also occupies a very wide ecological niche. Evidence suggests that Cetraria aculeata has evolved and diversified in the Northern Hemisphere and colonised the Southern Hemisphere during the Pleistocene. Genetic isolation of populations indicates the absence of ongoing long range dispersal and genetic exchange between geographically isolated populations. We observe a hitherto unrecognized genetic diversity that may indicate ecotypic differentiation and speciation processes. Mediterranean and Polar populations differ not only genetically, but also in ecophysiological properties. Ongoing common garden experiments will have to show whether genetically fixed adaptation or acclimation is responsible for these differences. The genetic structure of the photobiont is best explained by climatic differences between localities, but codispersal with the mycobiont plays an important role as well. Taken together, these results indicate that a photobiont switch in the past enabled C. aculeata to widen its ecological niche, with subsequent genetic isolation of populations. Photobiont switches may play a crucial role in speciation processes of lichens. A combination of ecophysiological and phylogeographic studies with experimental approaches is necessary to better understand the reaction of lichens to changing environmental conditions. Copyright Christian Printzen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. MycoKeys 6: 33–53 (2013) doi: 10.3897/mycokeys.6.3185 www.pensoft.net/journals/mycokeys A peer-reviewed open-access journal
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Pleistocene expansion of the bipolar lichen Cetraria aculeata into the Southern hemisphere.
Molecular ecology, 2013Co-Authors: Fernando Fernández-mendoza, Christian PrintzenAbstract:Many boreal and polar lichens occupy bipolar distributional ranges that frequently extend into high mountains at lower latitudes. Although such disjunctions are more common among lichens than in other groups of organisms, the geographic origin of bipolar lichen taxa, and the way and time frame in which they colonized their ranges have not been studied in detail. We used the predominantly vegetative, widespread lichen Cetraria aculeata as a model species. We surveyed the origin and history of its bipolar pattern using population genetics, phylogenetic and genealogical reconstruction methods. Cetraria aculeata originated in the Northern Hemisphere and dispersed southwards during the Pleistocene. The genetic signal suggests a Pleistocene dispersive burst in which a population size expansion concurred with the acquisition of a South-American range that culminated in the colonization of the Antarctic.
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Low genetic diversity in Antarctic populations of the lichenforming ascomycete Cetraria aculeata and its photobiont
Polar Research, 2012Co-Authors: Stephanie Domaschke, Fernando Fernández-mendoza, Miquel A. Garcia, María P. Martín, Christian PrintzenAbstract:Lichens, symbiotic associations of fungi (mycobionts) and green algae or cyanobacteria (photobionts), are poikilohydric organisms that are particularly well adapted to withstand adverse environmental conditions. Terrestrial ecosystems of the Antarctic are therefore largely dominated by lichens. The effects of global climate change are especially pronounced in the maritime Antarctic and it may be assumed that the lichen vegetation will profoundly change in the future. The genetic diversity of populations is closely correlated to their ability to adapt to changing environmental conditions and to their future evolutionary potential. In this study, we present evidence for low genetic diversity in Antarctic mycobiont and photobiont populations of the widespread lichen Cetraria aculeata. We compared between 110 and 219 DNA sequences from each of three gene loci for each symbiont. A total of 222 individuals from three Antarctic and nine antiboreal, temperate and Arctic populations were investigated. The mycobiont diversity is highest in Arctic populations, while the photobionts are most diverse in temperate regions. Photobiont diversity decreases significantly towards the Antarctic but less markedly towards the Arctic, indicating that ecological factors play a minor role in determining the diversity of Antarctic photobiont populations. Richness estimators calculated for the four geographical regions suggest that the low genetic diversity of Antarctic populations is not a sampling artefact. Cetraria aculeata appears to have diversified in the Arctic and subsequently expanded its range into the Southern Hemisphere. The reduced genetic diversity in the Antarctic is most likely due to founder effects during long-distance colonization. The environmental conditions of the Antarctic are among the most adverse on Earth and are generally characterized by low mean annual temperatures, high wind velocities, extreme drought and extended periods of darkness. The effects of global climate change are especially pronounced in parts of the Antarctic (Turner et al. 2005). Air temperature in the maritime Antarctic has steadily increased within the last years (Smith & Stammerjohn 1996; Turner et al. 2005). On the western Antarctic Peninsula a temperature increase of more than 2.5 K has been observed over the last 50 years. The overall effect of such a temperature increase on terrestrial Antarctic organisms could be beneficial. For example, glacial melting will increase the availability of terrestrial (page number not for citation purpose) Keywords Genetic diversity; lichens; Cetraria aculeata; Trebouxia jamesii; polar lichens; global change (Published: 27 March 2012) Citation: Polar Research 2012, 31 , 17353, DOI: 10.3402/polar.v31i0.17353 To access the supplementary material to this article 'Supplementar tables 6-8' please see Supplementary files in the column to the right (under Article Tools)
Nicolas Gouault - One of the best experts on this subject based on the ideXlab platform.
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separation of a mixture of paraconic acids from Cetraria islandica l ach employing a fluorous tag catch and release strategy
Tetrahedron Letters, 2007Co-Authors: David Horhant, Anne-cécile Le Lamer, Joël Boustie, Philippe Uriac, Nicolas GouaultAbstract:A light-fluorous catch and release approach application has been designed to the separation of a mixture of three paraconic acids extracted from the Island moss (Cetraria islandica (L.) Ach.). The (+)-protolichesterinic acid was caught and released via a Michael/retro-Michael addition sequence with a fluorous thiol, while the resulting two other compounds were classically separated, allowing the isolation of (+)-roccellaric acid for the first time in this lichen.
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Separation of a mixture of paraconic acids from Cetraria islandica (L.) Ach. employing a fluorous tag—catch and release strategy
Tetrahedron Letters, 2007Co-Authors: David Horhant, Anne-cécile Le Lamer, Joël Boustie, Philippe Uriac, Nicolas GouaultAbstract:A light-fluorous catch and release approach application has been designed to the separation of a mixture of three paraconic acids extracted from the Island moss (Cetraria islandica (L.) Ach.). The (+)-protolichesterinic acid was caught and released via a Michael/retro-Michael addition sequence with a fluorous thiol, while the resulting two other compounds were classically separated, allowing the isolation of (+)-roccellaric acid for the first time in this lichen.
K. Ingólfsdóttir - One of the best experts on this subject based on the ideXlab platform.
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immunologically active 1 3 1 4 α d glucan from Cetraria islandica
Phytomedicine, 1999Co-Authors: E S Olafsdottir, K. Ingólfsdóttir, K. Jurcic, Hilde Barsett, Smestad B Paulsen, Hildebert WagnerAbstract:Summary A polysaccharide, Ci-3, resembling isolichenan except with a much higher degree of polymerization, has been isolated from the water extract, as well as from the alkali extract, of the lichen Cetraria islandica (L.) using ethanol fractionation, dialysis, ion-exchange chromatography and gel filtration. The mean Mr of Ci-3 was determined to be 2000 kD, compared to 6–8 kD reported for isolichenan. The structure of Ci-3 was elucidated and found to be composed of (1→3)- and (l→4)-α-D-glucopyranosyl units in the ratio of 2:1, using methanolysis, methylation analysis, optical rotation and NMR spectroscopy. The immunomodulating activity of Ci-3 was tested in an in vitro phagocytosis assay and anti-complementary, and proved to be active in both tests.
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Immunologically active (1→3)-(1→4)-α-D-Glucan from Cetraria islandica
Phytomedicine : international journal of phytotherapy and phytopharmacology, 1999Co-Authors: Elin S. Olafsdottir, K. Ingólfsdóttir, K. Jurcic, Hilde Barsett, B. Smestad Paulsen, Hildebert WagnerAbstract:Summary A polysaccharide, Ci-3, resembling isolichenan except with a much higher degree of polymerization, has been isolated from the water extract, as well as from the alkali extract, of the lichen Cetraria islandica (L.) using ethanol fractionation, dialysis, ion-exchange chromatography and gel filtration. The mean Mr of Ci-3 was determined to be 2000 kD, compared to 6–8 kD reported for isolichenan. The structure of Ci-3 was elucidated and found to be composed of (1→3)- and (l→4)-α-D-glucopyranosyl units in the ratio of 2:1, using methanolysis, methylation analysis, optical rotation and NMR spectroscopy. The immunomodulating activity of Ci-3 was tested in an in vitro phagocytosis assay and anti-complementary, and proved to be active in both tests.
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Quantitative determination of protolichesterinic- and fumarprotocetraric acids in Cetraria islandica by high-performance liquid chromatography
Journal of Chromatography A, 1997Co-Authors: G.a. Gudjónsdóttir, K. IngólfsdóttirAbstract:Abstract A quantitative reversed-phase HPLC method for the analysis of protolichesterinic- and fumarprotocetraric acids in Cetraria islandica (L.) Ach. is described. The compounds were extracted from dry plant material with acetone. HPLC analysis was performed using a LiChrosorb RP-8 column, isocratic elution and UV detection. The method was applied to the quantification of protolichesterinic- and fumarprotocetraric acids in plant material collected in various locations within Iceland. Results showed protolichesterinic acid content of Cetraria islandica to vary between 0.1–0.5% dry weight and fumarprotocetraric acid content to vary between 2.6–11.5% depending on collection site.
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In vitro susceptibility of Helicobacter pylori to protolichesterinic acid from the lichen Cetraria islandica.
Antimicrobial agents and chemotherapy, 1997Co-Authors: K. Ingólfsdóttir, G.a. Gudjónsdóttir, Martha Á. Hjálmarsdóttir, A Sigurdsson, A Brynjolfsdottir, Ólafur SteingrímssonAbstract:With reference to the traditional use of Cetraria islandica (Iceland moss) for relief of gastric and duodenal ulcer, plant extracts were screened for in vitro activity against Helicobacter pylori. (+)-Protolichesterinic acid, an aliphatic alpha-methylene-gamma-lactone, was identified as an active component. The MIC range of protolichesterinic acid, in free as well as salt form, was 16 to 64 micrograms/ml.
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Immunologically active polysaccharide from Cetraria islandica.
Planta medica, 1994Co-Authors: K. Ingólfsdóttir, K. Jurcic, Bettina Fischer, Hildebert WagnerAbstract:A new alkali-soluble polysaccharide has been isolated from Iceland moss, Cetraria islandica (L.) Ach., by ethanol fractionation, ion-exchange chromatography, and gel filtration. The mean M(r) was estimated to be 18,000. Sugar and methylation analysis, partial hydrolysis, and 13C-NMR spectroscopy showed the polysaccharide to be a branched galactomannan with a backbone composed of two structural elements; (1-->6)-linked alpha-D-mannopyranosyl and alpha-D-(1-->6)-galactopyranosyl units. The polysaccharide showed pronounced immunostimulating activity in an in vitro phagocytosis assay and in the in in vivo carbon clearance assay.
Fernando Fernández-mendoza - One of the best experts on this subject based on the ideXlab platform.
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Testing the correlation between norstictic acid content and species evolution in the Cetraria aculeata group in Europe
The Lichenologist, 2017Co-Authors: Tetiana Lutsak, Fernando Fernández-mendoza, Olga Nadyeina, Ayhan Şenkardeşler, Christian PrintzenAbstract:AbstractMost lichen-forming fungi are characterized by the production of secondary metabolites. Differences in metabolite patterns have frequently served to distinguish lichen taxa with subsequent controversies about the rank of chemical variants (chemotype, variety, subspecies or species). Using a model system, we investigate whether production of norstictic acid within a group of lichenized ascomycetes is correlated with phylogenetic patterns, population differentiation or single and multi-locus haplotypes. Our study is based on DNA sequences of three gene loci (ITS, GPD, mtLSU) together with HPLC (311) and TLC (594) data from a total of 594 samples of three closely related fruticose lichens: Cetraria aculeata and C. muricata without norstictic acid, and C. steppae with norstictic acid. In nature, C. aculeata and C. steppae often occur together and the status of C. steppae as a separate species has been questioned. Our results show geographical but no phylogenetic structure of norstictic acid production and few significant associations between genetic clusters and the occurrence of norstictic acid. All frequently distributed haplotypes display differences in norstictic acid content. The few associations at the population level are most likely a by-product of spatial genetic structure, because norstictic acid was expressed only in individuals from the Mediterranean-Central Asian part of the study area. We conclude that the production of norstictic acid in the C. aculeata group is most likely triggered by the environment (climate, edaphic factors, associated symbionts). Cetraria steppae might be a different evolutionary lineage restricted to warm temperate regions but it is not uniquely characterized by the presence of norstictic acid.
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Mycobiont-photobiont interactions of the lichen Cetraria aculeata in high alpine regions of East Africa and South America
Symbiosis, 2016Co-Authors: Tetiana Lutsak, Fernando Fernández-mendoza, Paul Kirika, Melaku Wondafrash, Christian PrintzenAbstract:Lichens represent an extremely successful symbiosis between fungi and photosynthetic partners. It has been suggested that lichens can enhance their adaptive potential and widen their ecological niches by associating with locally adapted photobionts. Based on a worldwide population sample of the lichen Cetraria aculeata we investigate the genetic diversity and composition of photobiont and mycobiont populations of this species with a special focus on tropical alpine regions that have never been studied before. Probably due to their geographic isolation and founder effects during colonization, tropical mycobiont populations display low genetical diversity. In sharp contrast, tropical photobiont populations are among the most diverse within the species and similar in composition to polar populations. These results support the hypothesis of photobiont switching as an adaptive strategy in lichens.
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Biogeography and ecology of Cetraria aculeata, a widely distributed lichen with a bipolar distribution
MycoKeys, 2013Co-Authors: Christian Printzen, Fernando Fernández-mendoza, Stephanie Domaschke, Sergiо Pérez-ortegaAbstract:Ecological and historical biogeography of lichens have rarely been studied in a concerted effort, but both aspects have to be taken into consideration when explaining the distributional patterns of species. This review summarizes, partly preliminary, results from a series of studies on phylogeography, ecophysiology and symbiotic interactions of the lichen Cetraria aculeata. This species is not only widespread but also occupies a very wide ecological niche. Evidence suggests that Cetraria aculeata has evolved and diversified in the Northern Hemisphere and colonised the Southern Hemisphere during the Pleistocene. Genetic isolation of populations indicates the absence of ongoing long range dispersal and genetic exchange between geographically isolated populations. We observe a hitherto unrecognized genetic diversity that may indicate ecotypic differentiation and speciation processes. Mediterranean and Polar populations differ not only genetically, but also in ecophysiological properties. Ongoing common garden experiments will have to show whether genetically fixed adaptation or acclimation is responsible for these differences. The genetic structure of the photobiont is best explained by climatic differences between localities, but codispersal with the mycobiont plays an important role as well. Taken together, these results indicate that a photobiont switch in the past enabled C. aculeata to widen its ecological niche, with subsequent genetic isolation of populations. Photobiont switches may play a crucial role in speciation processes of lichens. A combination of ecophysiological and phylogeographic studies with experimental approaches is necessary to better understand the reaction of lichens to changing environmental conditions. Copyright Christian Printzen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. MycoKeys 6: 33–53 (2013) doi: 10.3897/mycokeys.6.3185 www.pensoft.net/journals/mycokeys A peer-reviewed open-access journal
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Pleistocene expansion of the bipolar lichen Cetraria aculeata into the Southern hemisphere.
Molecular ecology, 2013Co-Authors: Fernando Fernández-mendoza, Christian PrintzenAbstract:Many boreal and polar lichens occupy bipolar distributional ranges that frequently extend into high mountains at lower latitudes. Although such disjunctions are more common among lichens than in other groups of organisms, the geographic origin of bipolar lichen taxa, and the way and time frame in which they colonized their ranges have not been studied in detail. We used the predominantly vegetative, widespread lichen Cetraria aculeata as a model species. We surveyed the origin and history of its bipolar pattern using population genetics, phylogenetic and genealogical reconstruction methods. Cetraria aculeata originated in the Northern Hemisphere and dispersed southwards during the Pleistocene. The genetic signal suggests a Pleistocene dispersive burst in which a population size expansion concurred with the acquisition of a South-American range that culminated in the colonization of the Antarctic.
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Low genetic diversity in Antarctic populations of the lichenforming ascomycete Cetraria aculeata and its photobiont
Polar Research, 2012Co-Authors: Stephanie Domaschke, Fernando Fernández-mendoza, Miquel A. Garcia, María P. Martín, Christian PrintzenAbstract:Lichens, symbiotic associations of fungi (mycobionts) and green algae or cyanobacteria (photobionts), are poikilohydric organisms that are particularly well adapted to withstand adverse environmental conditions. Terrestrial ecosystems of the Antarctic are therefore largely dominated by lichens. The effects of global climate change are especially pronounced in the maritime Antarctic and it may be assumed that the lichen vegetation will profoundly change in the future. The genetic diversity of populations is closely correlated to their ability to adapt to changing environmental conditions and to their future evolutionary potential. In this study, we present evidence for low genetic diversity in Antarctic mycobiont and photobiont populations of the widespread lichen Cetraria aculeata. We compared between 110 and 219 DNA sequences from each of three gene loci for each symbiont. A total of 222 individuals from three Antarctic and nine antiboreal, temperate and Arctic populations were investigated. The mycobiont diversity is highest in Arctic populations, while the photobionts are most diverse in temperate regions. Photobiont diversity decreases significantly towards the Antarctic but less markedly towards the Arctic, indicating that ecological factors play a minor role in determining the diversity of Antarctic photobiont populations. Richness estimators calculated for the four geographical regions suggest that the low genetic diversity of Antarctic populations is not a sampling artefact. Cetraria aculeata appears to have diversified in the Arctic and subsequently expanded its range into the Southern Hemisphere. The reduced genetic diversity in the Antarctic is most likely due to founder effects during long-distance colonization. The environmental conditions of the Antarctic are among the most adverse on Earth and are generally characterized by low mean annual temperatures, high wind velocities, extreme drought and extended periods of darkness. The effects of global climate change are especially pronounced in parts of the Antarctic (Turner et al. 2005). Air temperature in the maritime Antarctic has steadily increased within the last years (Smith & Stammerjohn 1996; Turner et al. 2005). On the western Antarctic Peninsula a temperature increase of more than 2.5 K has been observed over the last 50 years. The overall effect of such a temperature increase on terrestrial Antarctic organisms could be beneficial. For example, glacial melting will increase the availability of terrestrial (page number not for citation purpose) Keywords Genetic diversity; lichens; Cetraria aculeata; Trebouxia jamesii; polar lichens; global change (Published: 27 March 2012) Citation: Polar Research 2012, 31 , 17353, DOI: 10.3402/polar.v31i0.17353 To access the supplementary material to this article 'Supplementar tables 6-8' please see Supplementary files in the column to the right (under Article Tools)
Edit Farkas - One of the best experts on this subject based on the ideXlab platform.
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DISTRIBUTION OF THE LEGALLY PROTECTED LICHEN SPECIES Cetraria ISLANDICA IN HUNGARY
2015Co-Authors: Mónika Sinigla, László Lőkös, Nóra Varga, Edit FarkasAbstract:Cetraria islandica is a rare lichen species with 20 known localities in Hungary. It became legally protected in Hungary in 2013. However, its distribution, habitat preferences and population dynamical conditions are insuffi ciently known and the species is still regarded as rare. Th e species is discussed on the basis of its Hungarian representatives and the so far revealed localities are presented on an updated distribution map.
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DISTRIBUTION OF THE LICHEN SPECIES Cetraria ACULEATA IN HUNGARY
Studia botanica hungarica, 2014Co-Authors: Mónika Sinigla, László Lőkös, Nóra Varga, Edit FarkasAbstract:Cetraria aculeata became legally protected in Hungary in 2005. Though for several decades it was known from a few localities only, recently it turned out that it is more frequent than previously ascertained. However, its range of distribution is insufficiently known and the species is still regarded to be rare. The present assessment is based on its specimens from Hungary; the currently known data of occurrences are presented on an updated distribution map. The recent records from the Bakony Mts (Kiralyszentistvan, Soly), Mecsek Mts (Cserkut, Pecs) and the Velence Mts (Pazmand) are new to Hungary, and the one from the Godollő Hills (Erdőkertes) turned to be a recent confirmation of Boros’ old record (1962) at Vacegres locality.