Cladonia parasitica (Hoffm.) Hoffm.
Primary thallus formed by squamules of 1-2.5 mm in length and 0.5-1 mm in width with strongly incised margin in lace or even sometimes coralloid in appearance, arranged in a crust or in carpet, upper surface greenish, green- yellowish, greyish-green, brownish-green discoloring to sea-green or sea-cream in the absence of light or in old age, rarely with pale green granules if wet, lower surface paler to whitish. Podetions rare and scattered, most often deformed and twisted, irregularly branched, sometimes reduced to a coralloid appearance, 3-15 mm in height, scaly or granular, without cup or very deformed, carrying apothecia at their top. Apothecia sparse, globose, often in groups, pinkish-brown, reddish-brown, globular, 1-1.5 mm in diameter. Fusiform spores, 7-14 x 2.5-3.5 µm. Typically with abundant pycnidia in the form of raised black dots, clearly visible on the upper surface of the scales. Photobiont: trebouxioid. C-, K + bright yellow, KC +/- dirty yellow P + golden yellow to orange. Especially forest species of oceanic forests, mainly on moss, coming at the base of the trunks or on the top of the large more or less rotten roots of conifers or deciduous trees, sometimes directly on soil humus, see: Cladonia parasitica forme détriticole au sol ; sometimes also on mossy rocks or directly on rotten, damp wood. Beware of Cladonia incrassata whose apothecia are very small and red. N.B. Often in sterile carpet of poorly developed scales on bark, wood, rocks and then very difficult to distinguish from other species presenting this aspect.