Lichens marins

Description

Crustose thallus generally well defined, cracked surface, more or less rough and bumpy, whitish, greyish, often able to form mosaics in sheltered areas, concolorous hypothallus but often blackish in case of mosaic. Apothecia more or less numerous, immersed in the thallus, and very slightly protruding, 0.5 to 2 mm in diameter, discs flat, concolorous to the thallus or very pale brownish (unless parasitized!), sometimes covered with a greyish bloom, margin relatively thick, irregularly shaped and sinuous or angular, often prominent and raised on the thallus, whitish or paler, entire to crenate, persistent. Simple, colourless, elliptical spores, 9-15 x x 5-7 µm according to the literature Photobiont: green algae. Thallus: C- most often, or more rarely C+ orange, K+ yellow, KC+/- orange or golden yellow, P+/- yellow; disc of apothecia: C- or C+ orange (Very variable, but also because the commercial bleach solution usually used contains sodium hydroxide (NaOH)). "Species" with strong maritime affinities but can be found inland, growing on siliceous rocks that are not too acidic and sheltered, common in the xeric (and even mesic) supralittoral zone where it can form large mosaic colonies, also common in the aerohaline zone, much rarer inland.

N.B. Very frequently (and even almost always!) parasitized by Arthonia varians.

N.B. "Species" or highly variable taxon including some intermediate forms to Lecanora rupicola subsp. rupicola, are sometimes difficult to distinguish! We present here some forms that it is possible to distinguish on the ground (not limiting!):

Lecanora rupicola subsp. subplanata Disque des apothécies C+ jaune.

Lecanora rupicola subsp. subplanata Disque des apothécies C+ orange..

Lecanora rupicola subsp. subplanata forme maritime grise.

Lecanora rupicola subsp. subplanata morph. formant des mosaïques.

Lecanora rupicola subsp. subplanata morpho C- Cf.

Lecanora rupicola (L.) Zahlbr. subsp. subplanata (Nyl.) Leuckert & Poelt s.l.