3. Oligotrichum falcatum Steere 镰叶小赤藓 lian ye xiao chi xian
Bryologist 61: 115. f. 1–9. 1958. Psilopilum falcatum (Steere) Crum, Steere & Anderson, Bryologist 68: 434. 1965. Type: U.S.A. Alaska, Brooks Range, Franklin Mts., Mt. Chamberlin, Steere 18959 (holotype NY).
Plants small to medium-sized, male plants rather small, female ones 1–5 cm high, brownish green to reddish brown, usually in tufts. Leaves deeply cucullate, lanceolate, 1.5–2.5 mm × 0.6–1.0 mm, not clearly sheathing at base; margins serrate; costa rather broad, ending at leaf apex; ventral lamellae strongly wavy, 10–15 rows, 3–5 cells high, on the leaf back with only a few lamellae or spines; median cells rounded quadrate, 7–18 µm wide; basal cells elongate or nearly rectangular, 18–35 µm × 7–18 µm, thick-walled. Dioicous. Setae reddish brown, straight; capsules single, cylindrical, mostly curved; peristome teeth 32; opercula conic, with short beaks. Calyptrae cucullate, covered with sparse cilia. Spores spherical, 10–13 µm in diameter, verrucose.