Baeomyces rufus (Huds.) Rebent.
Thallus crustose, to 15 cm across, more or less smooth, nodulose, or granulose in appearance with minute rounded squamules, but the "granules" are always small, sometimes with soralia or schizidia present, grey-glaucous, greenish, grey-green tinged with brown in places. Apothecia globose, tip almost flat when mature, 1-2 mm diam., dark red-brown to pale dull pink-brown, not hollowed, sometimes sessile most often stalked, stipe white, to 5-6 mm tall. Asci 8-spored, elongate, 95 x 7 µm. Ascospores ellipsoid, simple, guttulate and therefore apparently 1-septate, 8-11 x 3-4.5 µm according to literature, 7-10 x 3-4 µm according to our measurements. Thallus: C-, K+ yellow, KC+ yellow, Pd+ orange. Photobiont : Coccomyxa. Not especially maritime, cosmopolitan, common particularly in recently disturbed gravelly or peaty acid soils and heathlands of aerohaline zone, on earth banks of paths, and also on sheltered degraded schists, but often sterile in this case. See Dibaeis baeomyces of which the thallus displays much bigger granules and pink hollow apothecia (see pictures for comparison).
N.B. There is a form without a visible stipe, or reduced to a simple blade under the apothecium, see: Baeomyces rufus forma.