Opegrapha conferta  Anzi

    Thallus crustose, indistinct and inconspicuous, because very thin and evanescent, greyish, grey, grey-brownish or reduced to a simple greying of the substrate, very often absent and in this case this species is reduced to apothecia placed in fissures or around rock crystals. Apothecia lirelliform very prominent and as if they were just put on the substrate, arranged in small compact packs or in stars on subsrates more or less smooth or even in series forming networks in fissures of the substrate, thin cracks well visible, bright, black. Ascospores clavate, 3-septate, 16-20 x 4-6 µm. C-, K-, KC-, Pd-. Maritime trends, in fissures and cracks or around large crystals of acid or slightly acid rocks near the seashore.

N.B. This taxon was once considered as a member of the Arthonia (Opegrapha) calcarea group, as a special species or in form or variety.