Nuovo Giorn. Bot. Ital., n.s., 5: 205. 1898. Hypnum porphyreticum (Müll. Hal.) Paris, Index Bryol. Suppl. 208. 1900. Type: China. Shaanxi (Schen-si), Mt. Taibai, Giraldi 1776 (isotype NY, S).
Plants slender, yellowish green, in densely caespitose mats. Stems prostrate or ascending, 1–2 cm long, irregularly branched; central strand weakly differentiated; pseudoparaphyllia foliose or filamentous. Stem leaves erect or spreading, 0.6–0.9 mm × ca. 0.5 mm, abruptly narrowed from a cordate base to a shortly acuminate apex, upper part usually curved, tubular; margins serrulate; costae short, double, sometimes single, reaching beyond mid-leaf; median leaf cells linear, 25–60 mm × 3–5 mm; alar cells numerous, small, round or quadrate. Autoicous. Inner perichaetial leaves ovate-lanceolate, plicate, 1.2–1.5 mm × ca. 0.5 mm, abruptly narrowed, shortly acuminate; costae slender, reaching beyond 1/2 the leaf length. Setae 15–20 mm long, reddish; capsules reddish, cylindrical; endostome segments carinate; cilia 2–3, shorter than the segments, nodulose. Spores 13–16 mm in diameter, minutely papillose.