1. Oreoweisia laxifolia (Hook. f.) Kindb. 疏叶石毛藓 shu-ye shi-mao xian
Enum. Bryin. Exot. 69. 1888. Grimmia laxifolia Hook.f., Icon. Pl. 2: 194B. 1837. Didymodon laxifolius (Hook.f.) Mitt., J. Proc. Linn. Soc., Bot. Suppl. 1: 23. 1859. Syntypes. India: Sikkim, J. D. Hooker 103, 104, 105, 107.
Zygodon schmidii C. Müll., Bot. Zeit. 11: 60. 1853. Oreoweisia schmidii (C. Müll.) Paris, Index Bryol. 868. 1897.
Plants soft, rather large, to 5 cm high, yellowish green above, dark green below, not shiny, in dense tufts. Stems erect, often dichotomously branched. Leaves laxly spaced, curled when dry, erect-patent when moist, oblong-lingulate, up to 2.5 mm × 0.6 mm, somewhat sheathing at base, obtuse or blunt at apex; margins plane, irregularly serrulate near the apex; costa narrow, percurrent, with dorsal stereid band; upper cells quadrate to rounded-quadrate, thick-walled, mammillose on both surfaces; basal cells rectangular, ca. 60 µm × 18 µm, pellucid, thin-walled; alar cells not differentiated. Autoicous. Perichaetial leaves similar to upper stem leaves. Setae straight, orange-brown, ca. 10 mm long, twisted when dry; capsules reddish brown, erect, oblong-ovoid to short-cylindric, symmetric, contracted near the mouth, urns ca. 3 mm × 1 mm, exothecial cells rather thin-walled; peristome teeth inserted below the mouth, yellowish, smooth. Spores brownish, 18–20 µm in diameter, warty.