Placynthium subradiatum (Nyl.) Arnold
Flora, 67: 240, 1884. Basionym: Pannaria subradiata Nyl. - Act. Soc. Linn. Bordeaux, 21: 314, 1856.
Synonyms: Lecothecium controversum Anzi; Lecothecium radiosum Anzi; Lecothecium subradiatum (Nyl.) Dalla Torre & Sarnth.; Placynthium radiosum (Anzi) Jatta; Pterygium petersii Nyl.; Pterygium subradiatum (Nyl.) Nyl.; Wilmsia radiosa (Anzi) Körb.
Description: Thallus crustose-placodioid, olive brown to blackish grey, epruinose or faintly pruinose, forming orbicular to incomplete, 15(-20) mm wide rosettes, usually without a distinct prothallus, the central parts at first granulose-areolate, but soon dying off (sometimes regenerating with small warts or lobes), leaving narrow arcs of lobes; marginal lobes radiating, firmly adhering to the rock, usually strongly convex (subterete), 0.5-1.5 mm long, 0.03-0.25 mm wide, up to 0.15 mm thick, simple or branched, separate or more rarely contiguous. Thallus paraplectenchymatous throughout, the basal parts often brown-violet, with elongated hyphae and pale rhizohyphae more aboundant in the apical part of lobes. Apothecia rare, biatorine, black, up to 0.5 mm across, immersed to sessile, with a distinct proper margin when young. Epithecium blue-green; hymenium colourless, I+ blue; paraphyses distinctly septate, sparingly branched; hypothecium pale brown. Asci 8-spored, apically thickened, with an amyloid cap. Ascospores 1-septate, hyaline, ellipsoid, (7.5-)10-13(-15) x (3-)4-6(-8) μm. Pycnidia to 125 μm in diam., the wall colourless in basal parts, blue-black near the ostiole. Conidia bacilliform, (3.5-)5-6(-7) x c. 1 μm. Photobiont cyanobacterial, Scytonema-like. Spot tests: all negative. Chemistry: without lichen substances.
Growth form: Crustose
Substrata: rocks
Photobiont: cyanobacteria, filamentous (e.g. Nostoc, Scytonema)
Reproductive strategy: mainly asexual, by thallus fragmentation
On otherwise dry surfaces with short periods of water seepage after rain
Commonnes-rarity: (info)
Alpine belt: extremely rare
Subalpine belt: very rare
Montane belt: rare
Dry submediterranean belt: rather common
Humid submediterranean belt: rather common
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
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Occurrence data
Predictive map
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (30855)
2001/11/29
detail of marginal lobes
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (30855)
2001/11/29
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
Growth form: Crustose
Substrata: rocks
Photobiont: cyanobacteria, filamentous (e.g. Nostoc, Scytonema)
Reproductive strategy: mainly asexual, by thallus fragmentation
On otherwise dry surfaces with short periods of water seepage after rain
Commonnes-rarity: (info)
Alpine belt: extremely rare
Subalpine belt: very rare
Montane belt: rare
Dry submediterranean belt: rather common
Humid submediterranean belt: rather common
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
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (30855)
2001/11/29
detail of marginal lobes
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
P.L. Nimis; Owner: Department of Life Sciences, University of Trieste
Herbarium: TSB (30855)
2001/11/29
Pier Luigi Nimis - CC BY-SA 4.0
TSB 37610
