1. Dicranum assamicum Dix. 阿萨姆曲尾藓 a-sa-mu qu-wei xian
J. Bombay Nat. Hist. Soc. 39: 774. 1937. Type. India: Naga Hills, Bor 333.
Plants coarse, fairly robust, caespitose, up to 8 cm high, green to deeply brownish green, shiny, in dense tufts. Stems erect or ascending, simple or branched, homomallous. Leaves falcate-secund when dry, erect-patent when moist, narrowly lanceolate, up to 9 mm long, gradually narrowed from a somewhat sheathing base to a canaliculate or keeled subula; margins plane or slightly incurved, entire below, serrate in the upper third; costa slender, light brownish, percurrent, serrate at back above; median to upper cells elongate, rhomboidal, 45–55 µm × 8–10 µm, relatively thin-walled, not porose, spinosely projecting at the margins; basal cells rectangular, 75–85 µm × 12–16 µm, thick-walled, porose; alar cells quadrate to short-rectangular, tristratose, reddish brown. Dioicous. Perichaetial leaves shorter than the upper stem leaves, cylindrically clasping at base, abruptly narrowed to a short subula. Setae single, straight, yellowish, ca. 2.7 cm long; capsules erect, short-cylindric, ca. 4.7 mm × 1 mm, yellowish brown; opercula long-rostrate, ca. 0.3 mm long; peristome teeth ca. 0.48 mm long, divided to the middle, smooth above, usually perforate and transversely barred below, without vertical striation. Spores 20–23 µm in diameter, papillose, brownish.