Acarospora suzae Magn. var. suzae

    Thallus crustose, strongly fixed to its substratum, formed by flat or slightly protruding areoles of 1-1.5 mm, angular, positioned either connected or scattered (but rarely, and almost in fringes), these areoles can sometimes show a lobated looking towards the margin, with a matt upper surface, brown, dark brown, light brown, chocolate when dry, brown-olivish when moist, colour can become brown-blackish at edges and in the center of the thallus. 1-3 apothecia per areole, punctiformous then rounded, 0.1-0.4 mm diam., disc concave to planar, brown reddish or concolour to the thallus, without any clear exciple. Ascii with 150-200 spores. Spores largely ellipsoid, 4-5 x 2 µm. Negative chemical reactions. Seldom on slightly acid, dirty rocks or on rocks in old walls along the seashore. The synonymy of this taxa is very messy and interpretations are numerous ; we thus attribute this name with appropriate precautions. It seems to be the Acarospora nitrophila ss auct. brit. because the true Acarospora nitrophila seems to be a strictly nordic species. Cf. Acarospora impressula ss. auct. brit. darker, with less rounded apothecia and non-lobated areoles at the thallus margin.*