Ochrolechia androgyna Taxon saxicole maritime.

    Thallus crustose, thick, wrinkled, cracked, markedly verrucose, warts rounded, white-yellowish, pale grey-yellowish, more or less covered with piles of soredia, rounded and convex, yellowish, grey-yellowish, potentially covering important sections, prothallus whitish. Most often sterile, but fertile specimen may be observed notably in the islands West of Brittany with scattered apothecia, 2-5 mm diam., disc concave, orange, yellow-orange, exciple markedly sorediate. Asci in club, 110-130 x 40-50 µm with 8 spores. Simple, ovoid, colorless spores but a little graying in old age and a granular content in optical section, 30-45 x 12-20 µm according to the literature, 28-50 x 15-25 µm according to our measurements. C + scarlet, K +/- yellow then orange, KC + red, P-. Photobiont: Chlorococcoid.  This taxon is restricted to seashore habitats and it has been observed only on very exposed rocks in the aerohaline zone of heads, capes and islands of Western Brittany.

_ Not to be confused with some forms of Pertusaria pluripuncta that share the same habitat and of which the thallus is devoid of soredia, with larger warts, and K+ yellow,  C+ orange, Pd+ red-orange.

_ See Lecanora poliophaea whose colored chemical reactions are negative.

N.B. This very particular taxon deserves to be separated (and renamed) from Ochrolechia androgyna which is a collective species.