Aspicilia viridescens (A. Massal.) Hue

      Thallus crustose, strongly areolate, areola more or less rounded or pustular, olive-gray, greenish-gray, gray-bronze, gray, hypothallus sometimes present, blackish. Apothecia by 1-3 per fertile areola, at first immerged in the thallus then more or less open, flat disc, blackish-gray, blackish, margin sometimes a little striated. Asci with 4 (6) spores. Spores hyaline, broadly elliptical, 17-30 x 10-15 µm. No significant color chemical reactions. Thermophilic species fairly common in the Mediterranean region, coming on non-calcareous rocks exposed to the sun.

N.B. Do not confuse with Aspicilia hoffmanniana morpho viridescens which grows on less dry calcareous substrates.