Thallus caespitose, variable in shape, forming small to large cushions on rocks or tree trunks. Fertile branches erect, 2-4 cm long, 0.8-2 mm wide, irregularly divided, ± terete, with numerous coralloid or phyllocladioid ramuli along branches and at base. Surface smooth, yellowish-green to grey-green occasionally tinged reddish, occasionally transversely cracked in larger branches, cortex 80-110 µm thick, covered with a thin (2-4 µm) epicortex. Algal layer 60-90 µm thick, continuous beneath cortex. Apothecia occasional, 1-3 mm diam., subterminal, opening at an early stage of development by irregular apical rupture of enclosing receptacle, occasionally with small, phyllocladioid branchlets along margin, mazaedium apical to subterminal. Asci 45-60 × 4-7 µm. Ascospores greyish to hyaline 7.5-8.9(-10) µm diam., often covered by dark carbonaceous material. Chemistry: K+ yellow or -, Pd+ orange or -. Sphaerophorin, isousnic, norstictic, (tr.) stictic and constictic acids. Four chemodemes are known, three being additive, producing constictic, or stictic and constictic acids in addition to isousnic and sphaerophorin, or producing only constant constituents isousnic acid and sphaerophorin.