Schaereria fuscocinerea (Nyl.) Clauzade & C. Roux morph fuscocinerea.

    Thalli crustose, spreading, 3-6 cm across, may form mosaics, areolate, areoles angular, smooth, flat to convex, 0.3-0.8 mm diam., brown-chocolate, brown-greyish, brown-darkish, greyish, blackish, but on the seaside in the sea spray zone there is a grey-blue form: Schaereria fuscocinerea forme gris-bleu, hypothallus often present, blackish. Apothecia immersed within areoles, 0.3-1 mm diam., irregular, disc flat to slightyly convex, dark-brown, blackish, exciple thin, inconspicuous, excluded finally. Ascospores simple, ellipsoid, colourlesss, 10-16 x 5-8 µm. Photobiont: Trebouxia. Cortex: C+/- red, K-, KC+/- red, Pd- ; Medulla: C+ red, K-, KC+ red, Pd-. On higly exposed and windy siliceous rocks (with a rather smooth surface) of cliffs. Associated species (or parasite?) of saxicolous crustose lichens and often together with  Rhizocarpon geographicum or Rhizocarpon richardii.

N. B. This species is rather dark and, based on its aspect, difficult to distinguish from Aspicilia or Rhizocarpon and probably is understated since its aspect may suggest other common species.