10. Brachythecium formosanum Takaki 台湾青藓 tai wan qing xian
J. Hattori Bot. Lab. 15: 2. 1955. Type: China. Taiwan, Taichong, Noguchi 7061.
Plants slender, yellowish green to dark green, glossy, in dense mats. Stems prostrate, ca. 1.5–3.0 cm long, loosely foliate, irregularly branched, often with brownish rhizoids; branches ascending, ca. 0.5–1.0 cm long, densely foliate, attenuate at tips. Stem and branch leaves similar, appressed when dry, erect-spreading when moist, ovate- or elliptical-lanceolate, 1.0–1.4 mm × 0.4–0.7 mm, concave, gradually acuminate, plicate, usually constricted at base; margins entire, reflexed below, serrulate above; costae ending about mid-leaf; median leaf cells narrowly rhomboidal, 30–45 µm × 5–6 µm, thin-walled; basal cells lax; alar cells quadrate, hyaline. Dioicous. Perichaetial leaves lanceolate, piliform at apex; costae indistinct. Setae slender, ca. 15 mm long, straight or slightly curved, reddish, smooth; capsules symmetric or slightly asymmetric, shortly cylindrical; opercula shortly conic-rostrate; peristome teeth double; endostome segments papillose, keeled, perforate; cilia 1. Spores ca. 17 µm in diameter, minutely papillose.