7. Dicranum fragilifolium Lindb., Öfvers. K. Sv. Vet-Akad. Förh. 14: 125. 1857.
Orthodicranum fragilifolium (Lindb.) Podp., Consp. Musc. Eur. 152. 1954.
Plants small to medium-sized, 1–5 cm high, green to pale yellowish green, weakly shiny, in compact tufts. Stems slender, densely foliate, erect, simple or rarely branched, radiculose below. Leaves appressed, slightly altered when dry, erect-spreading or somewhat falcate-secund when moist, narrowly lanceolate, 6–7 mm long, gradually narrowed to a linear, often fragile, channeled subulate acumen; margins plane, entire below, subentire or minutely serrulate near the apex; costa occupying ca. ¼ the leaf base width, filling most of the subula, excurrent, ending in a long, smooth hairpoint, smooth at back above; upper cells irregular quadrate to short-rectangular, thick-walled, smooth; basal cells elongate, rounded linear-rectangular, thick-walled, porose; alar cells usually quadrate to short-rectangular, inflated, yellowish brown at the margins, hyaline next to the costa. Dioicous. Male plants dwarfed. Perichaetial leaves convolute-sheathing at base, abruptly subulate. Setae single, straight, 1–2 cm long, yellowish; capsules cylindric, up to 2 mm long, slightly curved, asymmetric, inclined, distinctly furrowed when dry; opercula conic-rostrate, nearly as long as the urns; annuli in 1–2 rows of large cells, often deciduous; peristome teeth lanceolate, vertically striolate below the middle. Spores ca. 24 µm in diameter, minutely papillose.
Chinese specimens examined: HEILONGJIANG: Da Xing An Ling (Greater Khingan Mt.), C. Gao 12983 (IFSBH); Xiao Xing An Ling (Lesser Khingan Mt.), C. Gao 27584 (IFSBH); Xin-lin Forest Preserve, C. Gao 13080 (IFSBH). NEI MONGOL: Da Xing An Ling (Greater Khingan Mt.), P.-C. Chen & C. Gao 815, 917 (IFSBH), S.-E. Liu 8971 (MO). SICHUAN: Omei Shan (Mt.), Raven et al. 59 (MO). TAIWAN: Nan-tou Co., S. Nakanishi 326 (KU).
Habitat: on rotten wood, bases of trees, or wet rocks; Distribution: China, Japan, Russia, Europe, and North America.
Illustrations: C. Gao (ed.) 1994 (Pl. 120, figs. 1–11; Pl. 130, figs. 5–6).