The crust-like, radiating body of the lichen forms irregular patches or clumps and includes numerous false conidiomata, a type of asexual reproductive structure, within its thallus.

Its lobes, dark brown and slightly flattened at the top, form larger groups at the edges and contain an upper layer composed of loosely interwoven cells and a lower inner tissue that varies from reddish-orange to white.

In the centre, it has an areolate-squamulose (divided into small, scale-like sections) structure, forming irregular patches or clumps.

[1] In terms of reactions to standard chemical spot test, the medulla of Placolecis sublaevis is K+ (violet) in its upper yellow part, as well as P− and C−.

[1] This species is found in the high mountain regions of Yunnan and Sichuan in southeast China, specifically on exposed steep slopes adorned with limestone boulders near streams.