Thallus continuous to areolate, up to 2 cm diam., parasitic on the thallus of Pertusaria spp., greyish brown, dull; hypothallus indistinct; medulla KI– or faintly violet. – Apothecia up to 0.8 mm diam., black, epruinose, orbicular or sometimes confluent, weakly to strongly convex, immarginate; excipulum brownish black in the rim, dark brown in inner part, K+ red; hypothecium dark brown, K–; hymenium pale reddish brown; epihymenium dark reddish brown, K+ red; no crystals in the apothecia, hymenium inspersed with dark violet granules; ascospores 8 per ascus, eumuriform, dark green to dark brown, 25–34 × 15–20 µm. – Conidiomata not seen.
Growing on the thallus of Pertusaria spp. on calcareous schist.
The species is easily recognized by the brown thallus growing on Pertusaria species.