Cladonia rangiformis
Thallus: primary thallus squamulose, usually evanescent. Podetia forming dense to lax cushions, 2-6 cm tall, ca 1 mm diam., grey-white to grey-green, sometimes browned with a violet tinge at the apex, richly branched, the branches irregular and diverging at wide angles, forming spiky tufts with pointed apices, without scyphi, axils usually closed. Surface entirely corticate, distinctly mottled-areolate, attached squamules rather rare, small to medium in size, often slightly concave, the margin entire or coarsely toothed, the lower surface white-tomentose. Soredia absent. Photobiont a green alga (Asterochloris).
Anamorph: pycnidia common, at the branch tips, dark brown, ± sessile, ± cylindrical to ovoid, hardly constricted at the base, the contents hyaline.
Teleomorph: ascomata apothecia, very rare, brown, at apices of podetia, sometimes ± corymbose.
Chemistry: thallus C–, K+ pale yellow, KC–, Pd– (in ca 70% of collections) or Pd+ red, UV– (usually with atranorin and rangiformic acid, more rarely with fumarprotocetraric acid).
Assessed by Woods & Coppins (2012) as of Least Concern. It is a widespread species that occupies a fairly broad range of habitats.
Characterized by the richly branched thallus, the widely divergent branches with pointed apices and the K+ pale yellow reaction. The surface of older parts is distinctly mottled with green areolate patches of algae on a white background. Cladonia furcata is often darker or more brownish, the surface not so obviously areolate (crazy-paving effect, best seen when wet) and has fewer, less divergent, branches and is K–.
Primarily in lowland regions throughout the British Isles, often coastal. BLS map here.
On neutral or basic grassland, chalk-flint grassland, cliffs and sand dunes.