Cladonia brevis  

Primary thallus persistent. Squamules small, 1-3 mm long, lobed, glaucous green and ± cracked on the upper surface, white arachnoid below, not sorediate. Podetia to 8 mm in length though sometimes undeveloped, unbranched or branched near the apex, flattened, the surface corticate and areolate.
Teleomorph: ascomata apothecia, brown, at the tips of podetia. Pycnidia large, black, constricted at the base, on the primary thallus.
Chemistry: thallus Pd+ yellow, K–, KC–, C–, UV– (psoromic and 2’-O-demethylpsoromic acids).