Cladonia caespiticia (Pers.) Flörke
Thallus made of squamules 0.2-0.7 cm long and 0.1-0.3 cm wide, margins markedly indented and incised, erected and packed, forming a dense carpet, whith upper surface grey-greenish, pale-green with sometimes a frozen looking, dark-brown pycnidia, lower surface whitish. Podetions absent or rare, small 1-5 mm in height, 0.5-1.5 mm in width. Apothecia scarce, pale brown, brown-reddish, similar to a small fungus, coming directly on the upper side of squamules, sessile or on short, hyaline to brown-pink pale stalks of max. 5 mm high. Ascii club-shaped to subcylindrical, 50-60 x 8-15 µm according to our measurements, with 8-spored in a spiral. Ascospores narrowly ellipsoid, simple, colourless, (12) 13-16 (17) x 3.5-4.5 µm according to our measurements. Photobiont: trebouxioid. C-, K-, KC-, Pd+ red. Uncommon species with lignicolous tendencies growing on mossy soil and embankments rich in woody debris or towards the base of trunks, also on stumps in old humid forests.
_ Resembles to Cladonia parasitica of which the more delimited and thiner squamules are sorediated and K+ yellow-orange and Pd+ yellow.
N.B. This species is frequently sterile or shows weakened or shapeless apothecia, then only differentiated by its frozen-like squamules.