Collema glebulentum (Cromb.) Degel.

H. Magn. ex Degel., Symb. Bot. Upsal., 13, 2: 406, 1954. Basionym: Leptogium glebulentum Nyl. ex Cromb. - J. Bot., 20: 272, 1882.
Synonyms: Collema coralliferum Degel.; Collema furvellum Räsänen
Distribution: N - TAA (Nascimbene & al. 2021, 2022).
Description: Thallus foliose, homoiomerous, gelatinous, dark olive-green to black when dry,semi-transparent and (50-)65-135(-200) µm thick when wet, more or less deeply lobed, membranous, 3-8(-10) cm wide. Lobes closely to sometimes loosely adnate, 5-8 mm wide, 0.1-0.2 mm thick, the surface conspicuously folded, with ascending, never swollen margins. Isidioid outgrowths abundant, laminal and marginal, c. 0.1 mm thick, up to 1.5 mm long, globose when young, then cylindrical and coralloid, usually crowded and forming a dense, coarsely areolate crust in older parts of thallus. Lower surface paler, with white to brownish hapters. Upper and lower cortices absent, or lower surface pseudocorticate; parts of thallus sometimes paraplectenchymatous. Apothecia and pycnidia unknown. Photobiont cyanobacterial (Nostoc, the cells in long chains). Spot tests: all negative. Chemistry: without lichen substances.
Note: an arctic-alpine species found on basic siliceous rocks, more rarely on limestone, in humid situations near or above treeline; another record is in Swiss territory, near the Italian border with Lombardy.
Growth form: Foliose, narrow lobed
Substrata: rocks
Photobiont: cyanobacteria, filamentous (e.g. Nostoc, Scytonema)
Reproductive strategy: mainly asexual, by isidia, or isidia-like structures (e.g. schizidia)

Commonnes-rarity: (info)

Alpine belt: extremely rare
Subalpine belt: extremely rare
Oromediterranean belt: absent
Montane belt: absent
Submediterranean belt: absent
Padanian area: absent
Humid submediterranean belt: absent
Humid mediterranean belt: absent
Dry mediterranean belt: absent

pH of the substrata:


Solar irradiation:








Altitudinal distribution:


Predictive model
Herbarium samples

Einar Timdal - Source: - CC BY-NC

Curtis Randall Björk, - CC BY-SA 4.0
Boundary Ranges, British Columbia, Canada