Cetraria islandica (L.) Ach. subsp. islandica
Meth. Lich.: 293, 1803. Basionym: Lichen islandicus L. - Sp. Pl., 2: 1145, 1753.
Synonyms: Cetraria islandica f. platysmoides Sambo; Cetraria islandica var. platyna (Ach.) Ach.
Description: Thallus subfoliose to subfruticose, loosely attached, often forming large tufts, consisting of dorsiventral, flattened, elongate, ascending, 1-3(-4) cm wide and up to 6(-10) cm tall, often sparingly branched laciniae with often in-rolled margins bearing short (0.2-1 mm) marginal, pycnidia-bearing spinulose outgrowths. Upper surface dark brown in sun-forms to pale olive-green in shade, matt or somehow glossy, smooth or often slightly wrinkled, the basal parts often reddish; lower surface usually paler, with large, maculiform, irregular, white pseudocyphellae spread throughout the surface and the margins. Cortex 2-layered, with an external layer of brownish, thick-walled, paraplectenchymatous cells, and an inner layer of periclinally arranged hyphae; medulla white. Apothecia extremely rare, lecanorine, mostly subterminal, with a dark brown disc and an often crenulate thalline margin. Epithecium brownish; hymenium and hypothecium colourless. Asci 8-spored, narrowly clavate, with a small axial body and a distinct, K/I+ blue ring-structure in the rather large tholus, approaching the Lecanora-type. Ascospores 1-celled, hyaline, ellipsoid to ovoid, 6-10 x 3.5-5 μm. Pycnidia immersed at the top of the marginal spinules, often empty. Conidia fusiform, multiseptate, colourless, 6-7 x c. 1 μm. Photobiont chlorococcoid. Spot tests: cortex K-, C-, KC-, P-; medulla K- or K+ yellow-orange, C-, KC-, P+ yellow to orange or P-, UV-. Chemistry: medulla with fumarprotocetraric acid, and variable amounts of protocetraric and protolichesterinic acids.
Growth form: Fruticose
Substrata: soil, terricolous mosses, and plant debris
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by thallus fragmentation
Commonnes-rarity: (info)
Alpine belt: very common
Subalpine belt: extremely common
Montane belt: very rare
Dry submediterranean belt: absent
Humid submediterranean belt: absent
Padanian area: absent
pH of the substrata:
1 2 3 4 5
Solar irradiation:
1 2 3 4 5
Aridity:
1 2 3 4 5
Eutrophication:
1 2 3 4 5
Poleotolerance:
0 1 2 3
Altitudinal distribution:
1 2 3 4 5 6
Rarity
absent
extremely rare
very rare
rare
rather rare
rather common
common
very common
extremely common
Loading data...
Occurrence data
Predictive map
Current prediction (1981-2010)
Future prediction (2071-2100) SSP 1-2.6
Future prediction (2071-2100) SSP 5-8.5Predictive maps according to Francesconi et al. 2025
Einar Timdal - Source: http://nhm2.uio.no/lav/web/index.html - CC BY-NC
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (14285)
2001/12/05
marginal pycnidia
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (34442)
2002/01/14
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (34442)
2002/01/14
pseudocyphellae
Andres Saag; Owner: University of Tartu
Gabriele Gheza, Tromello (PV); Owner: Gabriele Gheza, Tromello (PV)
Giancarlo Medici; Owner: Giancarlo Medici
Sweden, Svezia
2010
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
Juri Nascimbene - CC BY-SA 4.0; Owner: ITALIC - Dyades Project - Dept. of Life Sciences, University of Trieste
Italy, Trentino-Alto Adige, Trento, Monte Bondone
2014
Helena Rodriguez
Spain, Galicia, Peña Trevinca
06.2019
Helena Rodriguez
Spain, Galicia, Peña Trevinca
06.2019
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Pyrénées Cauterets
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Pyrénées Cauterets
Jacques Haine - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Alpes Maurienne
Jacques Haine - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Alpes Maurienne
Felix Schumm - CC BY-SA 3.0
12616 Schweiz, Berner Oberland, Sustenpaß östlich von Meiringen, Weg vom Vorfeld des Steingletschers zum Hotel Steingletscher (46°43.861' N, 8°25.616' E, 1890 m); bei 2010 m. F. Schumm
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Fürth, Hainberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Fürth, Hainberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Nürnberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Nürnberg
Wolfgang von Brackel - CC BY-4.0
Germay, Bavaria, Bayerwald, Arber
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Triin Aimla; Owner: University of Tartu
Hillmann J. 1936. Parmeliaceae. In: Rabenhorst’s Kryptogamen-Flora von Deutschland, Österreich und der Schweiz. 2nd, IX, Die Flechten, Abt. 5, 3. Borntraeger\Leipzig, pp. 1-309.
Hillmann J. 1936. Parmeliaceae. In: Rabenhorst’s Kryptogamen-Flora von Deutschland, Österreich und der Schweiz. 2nd, IX, Die Flechten, Abt. 5, 3. Borntraeger\Leipzig, pp. 1-309.
as var. platyna
Growth form: Fruticose
Substrata: soil, terricolous mosses, and plant debris
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly asexual, by thallus fragmentation
Commonnes-rarity: (info)
Alpine belt: very common
Subalpine belt: extremely common
Montane belt: very rare
Dry submediterranean belt: absent
Humid submediterranean belt: absent
Padanian area: absent
pH of the substrata:
| 1 | 2 | 3 | 4 | 5 |
Solar irradiation:
| 1 | 2 | 3 | 4 | 5 |
Aridity:
| 1 | 2 | 3 | 4 | 5 |
Eutrophication:
| 1 | 2 | 3 | 4 | 5 |
Poleotolerance:
| 0 | 1 | 2 | 3 |
Altitudinal distribution:
| 1 | 2 | 3 | 4 | 5 | 6 |
Rarity
absent
extremely rare
very rare
rare
rather rare
rather common
common
very common
extremely common
Loading data...
Occurrence data
Predictive map
Current prediction (1981-2010)Future prediction (2071-2100) SSP 1-2.6Future prediction (2071-2100) SSP 5-8.5Predictive maps according to Francesconi et al. 2025
Einar Timdal - Source: http://nhm2.uio.no/lav/web/index.html - CC BY-NC
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (14285)
2001/12/05
marginal pycnidia
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (34442)
2002/01/14
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (34442)
2002/01/14
pseudocyphellae
Andres Saag; Owner: University of Tartu
Gabriele Gheza, Tromello (PV); Owner: Gabriele Gheza, Tromello (PV)
Giancarlo Medici; Owner: Giancarlo Medici
Sweden, Svezia
2010
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Italy, Veneto, Belluno, Casera Razzo, 1900 m
09.09.2016
Juri Nascimbene - CC BY-SA 4.0; Owner: ITALIC - Dyades Project - Dept. of Life Sciences, University of Trieste
Italy, Trentino-Alto Adige, Trento, Monte Bondone
2014
Helena Rodriguez
Spain, Galicia, Peña Trevinca
06.2019
Helena Rodriguez
Spain, Galicia, Peña Trevinca
06.2019
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Walter Obermayer CC BY-SA 4.0 - Source: Lichens of Noricum - http://lichens-of-noricum.uni-graz.at/
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
Sweden
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Pyrénées Cauterets
Bernard Bouffinier - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Pyrénées Cauterets
Jacques Haine - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Alpes Maurienne
Jacques Haine - Source: http://www.lichensmaritimes.org/index.php?task=fiche&lichen=1328&lang=en
France, Alpes Maurienne
Felix Schumm - CC BY-SA 3.0
12616 Schweiz, Berner Oberland, Sustenpaß östlich von Meiringen, Weg vom Vorfeld des Steingletschers zum Hotel Steingletscher (46°43.861' N, 8°25.616' E, 1890 m); bei 2010 m. F. Schumm
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Moorkopf
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Bayerwald, Schneeberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Fürth, Hainberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Fürth, Hainberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Nürnberg
Wolfgang von Brackel - CC BY-4.0
Germany, Bavaria, Nürnberg
Wolfgang von Brackel - CC BY-4.0
Germay, Bavaria, Bayerwald, Arber
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Collezione lichenologica Abramo Massalongo del Museo di Storia Naturale G. Ligabue di Venezia - Autori: Seggi, Linda; Trabucco, Raffaella Proprietà: Fondazione Musei Civici di Venezia - CC BY-NC
Italy, Veneto, M. Baldo
Triin Aimla; Owner: University of Tartu
Hillmann J. 1936. Parmeliaceae. In: Rabenhorst’s Kryptogamen-Flora von Deutschland, Österreich und der Schweiz. 2nd, IX, Die Flechten, Abt. 5, 3. Borntraeger\Leipzig, pp. 1-309.
