23. Brachythecium perscabrum Broth. 疣柄青藓 you bing qing xian
Symb. Sin. 4: 107. 1929. Type: China. Yunnan, Salwin, Handel-Mazzetti 9368 (holotype H).
Plants small, slender, soft, yellowish green, somewhat glossy, in loose mats. Stems prostrate, to 2 cm long, irregularly branched, branches to 1.0 cm long, simple or with branchlets. Stem leaves broadly ovate, 1.0–1.4 mm × 0.57–0.61 mm, shortly acuminate, often twisted at apex; margins nearly entire or serrulate near leaf apex; costae stout, ending just above mid-leaf; median leaf cells linear, 70–86 µm × 5–7 µm; alar cells markedly differentiated, extending close to costa at leaf base, clearly decurrent at base; branch leaves ovate-lanceolate, 1.0–1.4 mm × 0.36–0.41 mm, slenderly acuminate at apex, strongly constricted, somewhat decurrent at base; margins serrulate near leaf apex, entire below. Autoicous. Setae ca. 15–18 mm long, papillose throughout; capsules ellipsoidal, often curved, dark brown; peristome double; exostome teeth lanceolate, 500 µm high, 81 µm wide at base, trabeculate above, cross-striolate below; endostome segments linear, as long as exostome teeth; basal membrane high; cilia long, nearly as long as the segments. Spores not seen.