17. Racomitrium lanuginosum (Hedw.) Brid. 白毛砂藓 bai-mao sha xian
Muscol. Recent. Suppl. 4: 79. 1819. Trichostomum lanuginosum Hedw., Sp. Musc. Frond. 109. 1801. Type. Europe.
Racomitrium hypnoides Lindb., Öfvers. Förh. Kongl. Svenska Vetensk.-Akad. 23: 552. 1866, nom. illeg.
Plants rather robust, 6–8 cm long, brownish green, sometimes grayish green due to long, hyaline hair-points, in loose, large and extensive cushions. Stems creeping, numerously bifurcately branched; central strand absent. Leaves imbricately appressed, often secund when dry, erect-spreading when moist, narrowly ovate-lanceolate, keeled above, 2.4–3.4 mm long, hyaline hair-points often well developed, sometimes shorter, decurrent at base, dentate and densely papillose; margins recurved on one side; costa strong, percurrent; leaf cells smooth, sinuosely thick-walled, unistratose at margins; upper cells rectangular, 12–23 µm × 4–6 µm; median cells longer, 16–32 µm × 4–5 µm; basal cells elongate-rectangular to linear, 23–46 µm × 3–4 µm; alar cells not differentiated, with only a row of rectangular to linear, hyaline cells, ca. 23–46 µm × 5 µm, with thin and straight walls. Sporophytes not seen.