11. Hydrogonium subpellucidum (Mitt.) Hilp. 亮叶石灰藓 liang-ye shi-hui xian
Beih. Bot. Centralbl. 50(2): 622. 1933. Barbula subpellucida Mitt., J. Proc. Linn. Soc., Bot., Suppl. 1: 35. 1859. Syntypes. Sikkim: Royle s.n. (lectotype NY); China: Xizang (Tibet), T. Thomson 121 (NY).
Hydrogonium subpellucidum var. hyaloma Herz., J. Hattori Bot. Lab. 14: 60 f. 20. 1955.
Plants medium-sized, 30–45 mm high, soft, bright green to yellowish green, in dense tufts. Stems simple or branched; central strand weakly differentiated. Leaves involute to contorted when dry, erect-spreading when moist, ovate-lanceolate, 1.6–3.0 mm × 0.5–0. 8 mm, rather suddenly narrowed to an acute apex; margins plane, entire in the lower half, serrulate in the upper half; costa stout, percurrent, roughened or papillose on the back; upper leaf cells rounded quadrate to hexagonal, 10–20 µm × 7–12 µm, thin-walled, distinctly papillose; basal cells narrowly rectangular, 34–90 µm × 10–22 µm, smooth, hyaline. Dioicous. Perichaetial leaves not much differentiated. Setae slender, ca. 15 mm long, yellowish brown to reddish, more or less twisted; capsules erect, ovoid-cylindrical; peristome teeth linear, slightly twisted counterclockwise.