Nephroma resupinatum  

Thallus to ca 10 cm diam., forming rosettes or with ± unorientated lobes that often overlap especially at the centre. Lobes 5-17 mm wide, robust, the margins sometimes ascending, entire and rounded or crenulate to lobulate. Upper surface grey-brown to dark brown, undulate and sometimes weakly honeycombed, ± uniformly pubescent or finely subtomentose, occasionally with terete to dorsiventral phyllidia arising from irregular verrucae, sometimes associated with surface ridges. Medulla white. Lower surface pale tan, markedly tomentose, with scattered, raised, white papillae. True soredia and isidia absent. Photobiont cyanobacteria (Nostoc).
Anamorph: conidiomata pycnidia, rare, marginal, semi-immersed. Conidia 4-5 × 1-2 μm, bacilliform.
Teleomorph: ascomata apothecia, frequent, to 1.1(-1.5) cm diam., the subtending lobe markedly recurved, dorsal surface tomentose, coarsely scabrid and foveolate-reticulate. Ascospores 21-24 × 4-6 μm, fusiform, 3-septate. 
Chemistry: thallus and medulla C–, K–, KC–, Pd– (no distinguishing medullary substances detected by TLC).