Pycnothelia papillaria Dufour

    Primary thallus crustose, persistent, made of large granules, white-greyish, easily confused with other species, typically lying on a black background (produced by other parasited species?). Podetia simple or branched, conical, cylindrical, swollen, hollow and very fragile, to 1.5 cm tall but most often resricted to buds or cones, whitish tinged purple. Pycnidia often present at apices of podetia, visible as blackish to brown dots. Apothecia rare, visible as minute globules clustered at podetia apices, brown-red. Ascospores simple, ellipsoid, 10-15 x 4-5 µm. Photobiont: Trebouxioid. C-, K+ yellow, KC-, Pd-. Rather common in poor and acid heathlands or in mosses at Calluna stem level.

N.B. This species is common in heathlands in the aerohaline zone where it may be found under different aspects from  bare crust without podetia to fully fertile specimen.

N.B. Altered specimen are difficult to distinguish from some other grazed or recovering Cladonia species.