Orthodicranum montanum (Hedw.) Loeske

Plants usually very small, 5–10 mm high, sometimes up to 3 cm high, green to dark green or yellowish brown, in dense, compact tufts. Stems short, erect, weakly branched, radiculose below, usually producing numerous small branchlets with minute, crispate leaves near the apex. Leaves 1–3 mm long, strongly crispate when dry, flexuose when moist, narrowly lanceolate, gradually narrowed to a slightly concave acumen, not subtubulose, blunt or narrowly obtuse at the apex; margins slightly incurved, serrulate in the upper part, sometimes bistratose; costa percurrent to shortly excurrent; upper cells quadrate to subquadrate, 8–12 µm wide, obscure, thick-walled, mammillose on the dorsal surface; lower cells elongate, rectangular or irregular, thick-walled; alar cells brownish or sometimes hyaline and not well differentiated. Setae straight, 1.0–1.5 cm long, yellowish when young, reddish when old; capsules erect or slightly curved, somewhat furrowed when dry; annuli in 1–2 rows of cells, deciduous; opercula nearly as long as the urns. Spores 13–20 µm in diameter, yellowish, finely papillose.

Distribution: China, Korea, Japan, Russia, Europe, and North America.

Habitat: on rotten logs or bases of trees, rarely on rocks.

Orthodicranum montanum là một loài Rêu trong họ Dicranaceae. Loài này được (Hedw.) Loeske mô tả khoa học đầu tiên năm 1910.