Rhizocarpon norvegicum Räsänen

Feddes Repert., 52, 2: 141, 1943.
Synonyms:
Distribution: N - Frl (Tretiach & Hafellner 2000), TAA (Nascimbene & al. 2021, 2022), Lomb (Ravera & al. 2023).
Description: Thallus crustose, episubstratic, areolate, yellow-green, rarely delimited by a black prothallus, forming very small (0.2-0.5 cm) patches consisting of 2-10 areoles and 2-5 apothecia. Areoles dispersed or contiguous, 0.3-0.7 mm wide, more or less angular, usually strongly convex, smooth, dull or glossy. Cortex poorly differentiated, 30-50 µm thick; medulla white, I+ blue. Apothecia lecideine, black, 0.3-0.7 mm across, rounded-angular to round, with a slightly to strongly convex disc and a thin, soon excluded proper margin. Proper exciple reddish brown in outer part, K+ reddish violet; epithecium dark, with granules, K- or K+ reddish violet; hymenium colourless, 60-90 µm high; apices of paraphysoids capitate; hypothecium 100-200 µm high, brown, K-. Asci 8-spored, clavate, fissitunicate, with a well-developed tholus, lacking an ocular chamber, Rhizocarpon-type. Ascospores 1-septate, dark brown, ellipsoid, 9-15 x 6-7 µm, halonate. Photobiont chlorococcoid. Spot tests: medulla K-, C-, KC-, P-, or P+ yellow. Chemistry: rhizocarpic acid, with or without psoromic acid.
Note: a pioneer species of schistaceous, slightly calciferous or basic eruptive rocks in upland areas, which often starts the life-cycle on members of Acarosporaceae (Timdal in litt.).
Growth form: Crustose
Substrata: rocks
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
paras Acarosporaceae
Pioneer species

Commonnes-rarity: (info)

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

pH of the substrata:

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Solar irradiation:

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Aridity:

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Eutrophication:

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Poleotolerance:

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Altitudinal distribution:

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Predictive model
Herbarium samples

Author: Leif Stridvall - Source: http://www.stridvall.se/la/galleries.php



Pier Luigi Nimis CC BY-SA 4.0
TSB 41440



Pier Luigi Nimis CC BY-SA 4.0
TSB 41141



Pier Luigi Nimis CC BY-SA 4.0
TSB 41140