Bot. Z., 1861: 352, 1861. Basionym: Cladonia alcicornis var. firma Nyl. - Syn. Lich., 1: 191, 1858.
Synonyms: Cladonia foliacea var. firma (Nyl.) Vain.; Cladonia nylanderi Cout.
Distribution: N - TAA, Emil (Fariselli & al. 2020), Lig (Brunialti & al. 1999, Gheza & al. 2020). C - Tosc, Laz, Sar (Zedda 1995, 2002, 2002b, Nöske 2000, Zedda & al. 2010, Cogoni & al. 2011, Neuwirth 2018, Burgaz & al. 2020). S - Si (Burgaz & al. 2020).
Description: Primary thallus squamulose, the squamules prominent, persistent, forming dense mats, 0.5-2 cm long, 1-4 mm wide, mostly ascending, entire to slightly indented, often curved at apices when dry, glaucous green to grey-green above, reddish grey beneath, often darker toward the base. Podetia rare, hollow inside, greenish grey, funnel-shaped, sometimes proliferating from the center, with a continuous to shallowly areolate cortex. Apothecia extremely rare, dark brown, convex, on the margins of cups. Asci 8-spored, clavate, thickened at apex, with a K/I+ blue tholus and a K/I+ strongly blue outer gelatinous sheath, Cladonia-type. Ascospores 1-celled, hyaline, ellipsoid. Pycnidia dark, semi-immersed along the margins of cups or on the primary squamules, sessile, subglobose to ovoid. Conidia bacilliform. Photobiont chlorococcoid. Spot tests: K+ yellow, C-, KC-, P+ red, UV-. Chemistry: fumarprotocetraric acid, atranorin, and variable amounts of rangiformic acid.
Note: a mild-temperate lichen found on mineral, often base-rich soil in open Mediterranean grasslands.
Growth form: Fruticose
Substrata: soil, terricolous mosses, and plant debris
Photobiont: green algae other than Trentepohlia
Reproductive strategy: mainly sexual
Most common in areas with a humid-warm climate (e.g. most of Tyrrenian Italy)