Aspicilia cinerea (L.) Körb.

    Thallus crustose, 5-15 cm diam., thick, rimose to strongly areolate, areoles angular, very irregular, becoming warted, with a visible dark-grey hypothallus between areoles, surface rugose to verrucose, grey-smoke, pale grey, turning grey-brown, prothallus black, delimiting. Apothecia round, 1-3 per areole, 0,4-1 mm diam., at first slightly immersed then slightly emerging, disc concave to flat, matt black, thalline margin thick, persistent. Asci (6-)8-spored. Ascospores oblong to broadly ellipsoid, 12-22 x 6-13 µm, conidia (pycnidiospores) 11-16 x 1 µm. Photobiont: Chlorococcales. Thallus : C-, K+ red, Pd+ orange. Rare in our prospection area, on exposed siliceous rocks. N.B. There are several very close species with various interpretations according to the relative weight of characteristics analysed. Aspicilia intermutans, often confused near the seashore, is rather similar but with bigger spores: 20-28 x 11-14 µm. Aspicilia epiglyta  is darker brown or ochre, with rounder areoles, and disc warted, dark brown and ascopspores of 20-25 x 12-15 µm. Aspicilia cupreogrisea is pale blue to grey-blue, K+ yellow > red.  Pertusaria chiodectonoides shares the same chemical spot tests, but the areoles are bigger and tuberculate, and displays different apothecia. N.B. This species is considered here stricto sensu; we do not provide specimen locations in our prospection area, since peviously, lichenologists considered the species sensu lato and did not separate it from the others.*