Nephroma parile  

Thallus to ca 8 cm diam., forming rosettes or fragmentary, ± loosely appressed. Lobes broad and spreading, 3-8 (-10) mm wide, often thin, the margins entire or subcrenulate, rarely ascending. Upper surface smooth (rarely faintly honeycombed), dark bluish grey when wet, mid to dark red-brown when dry, with pustular marginal soralia which later spread on to the surface. Dorsal surface above apothecia ± smooth, sorediate. Soredia bluish grey to brown, + coarsely granular, often partially corticate and eroded. Isidia absent. Medulla white. Lower surface smooth to wrinkled, glabrous or in part subpubescent, rarely tomentose. Photobiont cyanobacteria (Nostoc).
Anamorph: conidiomata pycnidia, rare, marginal. Conidia bacilliform, 4-5 x ca 1 µm in size.
Teleomorph: ascomata apothecia, extremely rare, often small and immature, rounded to reniform, the disc red-brown-black. Ascospores 18-20 × 6-7 μm.
Chemistry: medulla K± yellow (hopane triterpenoids: T2, T3 and T5 and distinctive unidentified accessory substances).