Thallus effuse, minutely squamulose; squamules contiguous, pale cream to yellowish-green, slightly convex with a matt surface (0.2–)0.3–0.5 mm across with an effigurate margin; medulla I–. Photobiont Chlorella-like; cells 8–12 µm diam., dividing by binary fission.
Apothecia initially orbicular, slightly concave, pale orange, becoming flat 0.4–0.5(–0.8) mm diam. with a flexuose margin and a dark orange to red-brown disc; proper margin initially raised, rounded and smooth, 0.05 mm wide but becoming flexuose, not raised but remaining pale yellow. In section: proper Exciple 70–100 µm wide, composed of an intricate web of hyphae c. 2 µm wide. Hymenium c 150 µm tall, orange-brown, K+ crimson (anthraquinones); paraphyses simple to sparingly branched, 1–1.5 µm wide, becoming almost moniliform and somewhat swollen (3 µm wide), but not capitate, towards the apices. Asci cylindrical, Trapelia-type. 25–55 × 10–15 µm; ascospores (9–)10.33±0.89(–12) × (4.5–)4.92±0.47(–5.5) µm, l/b ratio (2.0–)2.15±0.245(–2.67) µm (n=12). Hypothecium hyaline (K–), 30–40 µm deep, composed of randomly orientated hyphae but forming a horizontal layer at the base.
Conidiomata not observed.
Chemistry. Thallus K–, C+ red, Pd–, gyophoric acid by TLC; anthraquinones in the apothecia.