Cladonia pocillum (Ach.) Grognot

    Like Cladonia pyxidata but with particularly well-developed, spreading, contiguous and overlapping basal squamules, ± imbricate, erect, forming compact rosettes, tightly appressed, except towards the margin where they are slightly up-turned, tip lobe margins, eroded, indented, upper surface green, grey-green, softly pulverulent, white below. Podetia 0.5-2 cm tall, topped by scyphi, 0.3-10 mm diam., coarsely granular corticate inside and on outer surface. Apothecia at scyphi margins, brown. Photobiont : Trebouxioid. Thallus : C-, K-, KC-, Pd+ red. Mainly on sandy calcareous dunes and weakly acid soils with other species of the Toninion caeruleonigricantis where it often is the host of other cyanobacteria lichens and to Diploschistes muscorum. N.B. This species probably is an ecotype of Cladonia pyxidata that displays smaller basal squamules and is not forming rosette.*