4. Syntrichia princeps (De Not.) Mitt. ´赤藓 chi xian
J. Proc. Linn. Soc., Bot., Suppl. 1: 39. 1859. Barbula princeps (De Not.) C. Müll., Syn. Musc. Frond. 1: 636. 1849. Tortula princeps De Not., Mem. Reale Accad. Sci. Torino 40: 288. 1838. Type. Sardinia, 1847, Rabenhorst s.n.
Plants medium-sized to large, 2.0–5.0 cm high, dark green to reddish brown, in dense tufts. Stems erect, simple or irregularly branched, radiculose at base; central strand present. Leaves appressed or somewhat contorted-curved when dry, spreading when moist, oblong-ligulate to spathulate, obtusely acute at apex, upper lamina broadly channeled or keeled, weakly sheathing at base; margins often recurved, crenulate by projecting papillae; costa rather stout, reddish brown, excurrent, ending in a long, hyaline awn, denticulate on the back or at tips; upper leaf cells quadrate to hexagonal, each cell densely covered with several C-shaped papillae; basal cells distinctly differentiated, rectangular, thin-walled, smooth, hyaline or reddish. Autoicous (synoicous). Setae elongate, straight, reddish; capsules erect, cylindrical; peristome teeth linear, twisted, papillose; basal membrane high.