4. Racomitrium barbuloides Card. 硬叶砂藓 ying-ye sha xian
Bull. Herb. Boissier, ser. 2, 8: 336. 1908. Type. Korea: Isl. Quelpaert, Faurie 102, 296.
Plants medium-sized, up to 3 cm long, green to yellowish green above, dark brownish below, in loose tufts. Stems creeping, densely pinnately branched, with short branches; central strand absent. Stem leaves slightly contorted, loosely imbricate when dry, erect-spreading when moist, ovate-lanceolate, keeled above, slightly plicate below, 3.1–3.4 mm × 0.9–1.3 mm, narrowly rounded-obtuse at apex, without hyaline hair-points; branch leaves contorted, sometimes undulate, imbricately appressed when dry, erect-spreading when moist, lanceolate, keeled above, plicate below, 2.6–2.9 mm × 0.5–0.6 mm, bluntly acuminate at apex, without hyaline hair-points; margins recurved on both sides; costa strong, disappearing below the apex; upper leaf cells quadrate or shortly rectangular, 6–16 µm × 5–6 µm, sinuosely thick-walled, papillose, unistratose at margins; median cells short-rectangular, 11–30 µm × 5–7 µm, sinuosely thick-walled, papillose; basal cells rectangular, 23–46 µm × 4–5 µm, strongly sinuosely thick-walled, papillose; alar cells differentiated, consisting of a group of 15–20 inflated, yellowish, quadrate to short-rectangular, thin-walled cells, 10–28 µm × 7–10 µm. Perichaetial leaves smaller than stem leaves. Setae erect, 10–15 mm long, reddish brown; capsules erect, ovoid to oblong-ovoid, reddish brown, ca. 3 µm long; peristome teeth linear, ca. 0.9 mm long, reddish brown, divided to the base, papillose. Spores not seen.