Ochrolechia tartarea (L.) Massal. forme corticole.
Thallus crustose, rather thick, markedly verrucose with large globose warts, pale greyish, pale grey-greenish, dull whitish, prothallus inconspicuous, white. Apothecia usually abundant, immersed and closed at first, then sessile, dispersed all over the thallus or clustered, sometimes irregular, 5-8 mm diam., discs concave to plane, pale brown-orange, pale orange, without pruine and sometimes sand sprinkled-like, exciple thick, sinuous, smooth or slightly coarse, concolourous to the thallus. Ascospores broadly ellipsoid, 40-70 x 20-40 µm. Thallus: C+ orange, K+ pale yellow, KC+ red, Pd-; discs: C+ red-orange, K-, KC+ red, Pd-. On barks of trees in woodlands of oceanic valleys or low in the mountains. N.B. Specimen presented here were found in the Iraty forest in the Basque country at an altitude of 1350 m. See Ochrolechia androgyna which is sorediate and some morphs of Ochrolechia parella that grow mainly on rocks and with less verrucose thalli. See also in Mediterranean montane zone a rather similar species: Ochrolechia balcanica.