Toninia aromatica (Turner ex Sm.) A. Massal.

  Thallus squamulose, formed of squamules up to 3-4 mm in their greatest length, rounded or irregular, flat or a little convex, whitish, pale gray to dark brown if dry, with greenish tones or even green if very moist (and the squamules then appear almost leafy), covered with warty spots or very pale grayish ridges which give it a fluffy aspect. Apothecia numerous, up to 1-1.5 mm in diameter, angular by compression with their neighbors, more or less flat or pruinose, black, margin more or less visible but persistent, thick and swollen in wet weather, black, epithecium greenish. Spores 3-septate, long elliptical with rounded apex, 12-23 x 3-6 µm. Photobiont: trebouxioid. Chemical spots tests negative. Species with more or less coastal affinities in our prospecting region, coming in the humid cracks of more or less basic or limestone rocks but also on the packed soil of limestone dunes or on friable alkaline rocks; its appearance is very different depending on whether the weather is humid (greenish scales and apothecia almost regular with a swollen margin) or dry (gray scales and "flocked" of whitish and "shriveled" apothecia). This species seems to be able in certain cases to associate (or parasitize?) with black cyanolichens and it is not rare to meet it on a very black background formed by these cyanolichens, in the particular case of Placynthium nigrum it seems to have been described as Toninia verrucarioides. N.B. To be compared in our prospecting region and on the seafront with Toninia mesoidea strictly coastal and confined to the area of ​​seawater projections and coming into the cracks of schistose and siliceous rocks.