Its thallus can grow over 5 cm wide, featuring long, straight, and separate lobes that are highly convex and tube-like, with a pale grey, slightly shiny upper surface adorned with cylindrical isidia.

The upper surface of the thallus is pale grey, slightly shiny, without a powdery coating (epruinose), and shows weak spotting.

It is covered with cylindrical isidia, which are the same colour as the thallus but may have a brown cap when young and often develop an erect, black bristle-like structure (cilium) at the top when older.

Black, slender cilia measuring 1–4 mm in length are present on the lower surface; these can be simple or occasionally once dichotomously branched.

The thallus contains atranorin in the upper cortex and constictic and protolichesterinic acids in the medulla, as confirmed by thin-layer chromatography.