Plants: dense, rigid, dark green to yellow-brown. Stems: with branching angle wide, branches firmly attached; pseudoparaphyllia foliose; rhizoids below or at abaxial leaf insertion, red-brown, smooth. Leaves: erect-spreading, 0.1–0.3 mm; base not much narrowed to insertion; margins entire or nearly so; alar cells subquadrate, region of 3–6+ cells; distal laminal cells oblong-rhombic, 2–3(–4):1. : Specialized asexual reproduction absent. Sexual: condition autoicous; perichaetial leaf margins entire or obscurely serrulate distally. Seta: 0.6–0.8 cm. Capsule: inclined to horizontal or rarely suberect, shortly oblong-cylindric, asymmetric, 0.8–1.2 mm, contracted below mouth when dry, neck short; stomata at base of capsule; annulus 2-seriate; operculum convex-conic, stoutly apiculate; exostome teeth yellow-brown; endostome cilia in groups of 2 or 3, well developed. Spores: 11–13 µm.
Diagnostic features of Platydictya confervoides include entire or obscurely serrulate leaf margins and short laminal cells, as well as a rupestral habitat.