Dicranum hamulosum Mitten 1891

Plants small to medium-sized, to 2.5 cm high, soft, yellowish to dull yellowish green, somewhat shiny, in compact tufts. Stems erect, closely foliate, simple or branched, radiculose at base; central strand present. Leaves 4–6 mm long, falcate-secund, crispate when dry, erect-spreading when moist, narrowly lanceolate, gradually narrowed to a long, subtubulose acumen; margins plane, entire below, bistratose above the middle, double-toothed in the upper part; costa stout, percurrent to shortly excurrent, spinose at back above; upper cells quadrate or irregularly linear-rectangular, mammillose at back; basal cells narrowly rectangular, linear at the margins, thick-walled, porose; alar cells well developed, inflated, thin-walled, mostly unistratose, occasionally bistratose, with some incrassate cells between the alar region and the costa. Dioicous. Perichaetial leaves sheathing at base, with costa excurrent ending in a long hairpoint. Setae single, ca. 12 mm long, straight to straight-sinuose when dry, reddish; capsules erect, short-cylindric, symmetric, slightly curved when dry; opercula straight, long-rostrate; annuli absent; peristome teeth linear-lanceolate, divided to the middle, papillose or indistinctly papillose above, faintly vertically striolate below. Spores 20–22 µm in diameter, pale yellowish, minutely papillose.

Distribution: China, Japan, and Russian Far East.

Habitat: on bases of trees.

Orthodicranum hamulosum (Mitt.) Broth., Nat. Pflanzenfam. (ed. 2) 10: 203. 1924. Dicranum crispo-falcatum Schimp. ex Besch., Ann. Sci. Nat. Bot. sér. 7, 17: 331. 1893. Dicranum fauriei Broth. & Paris, Bull. Herb. Boissier sér. 2, 2: 920. 1902. Dicranum perindutum Card., Bull. Herb. Boissier sér. 2, 7: 715. 1907. Dicranodontium tenii Broth. & Herz., Hedwigia 65: 150. 1925. Type. China: Yunnan, Kunming, Pe Yen Tsin, alt. 3000 m, Handel-Mazzetti 36 (holotype H). Synonymized by Frahm (1997).