29. Syntrichia Brid. 赤藓属 chi xian shu
J. Bot. (Schrader) 1(2): 299. 1801.
Plants usually medium-sized to large, sometimes rather robust, green to reddish brown, in loose or dense tufts. Stems erect, simple or irregularly branched, radiculose at base; central strand usually present, rarely absent. Leaves appressed or contorted-curved to somewhat crisped when dry, spreading or sometimes reflexed when moist, oblong-ligulate to spathulate, or narrowly ovate-lanceolate, rounded-obtuse to broadly acute or mucronate at apex, upper lamina broadly channeled or keeled, weakly sheathing at base; margins often recurved, crenulate by projecting papillae, usually forming a differentiated border, consisting of several rows of thick-walled, or sometimes elongated cells, yellowish or brownish, border rarely absent; costa rather stout, often reddish brown, excurrent, ending in a short to rather long awn, often denticulate on the back or at tips, costa rarely percurrent or ending below the apex, in cross section 1 dorsal stereid band present (which is exposed, not covered by parenchymatous epidermal cells) or sometimes the ventral stereid band very weakly developed; upper leaf cells subquadrate to rounded-hexagonal, each cell densely covered with several C-shaped papillae; basal cells distinctly differentiated, rectangular, thin-walled, hyaline, smooth. Autoicous or dioicous. Setae elongate, straight, yellowish brown; capsules erect or slightly inclined, cylindrical; peristome teeth 32, linear or filiform, twisted, papillose, rarely erect; basal membrane high; annuli differentiated; opercula conic-rostrate, with a long, oblique beak. Calyptrae cucullate, smooth. Spores spherical, small, yellowish green or reddish brown, smooth or finely papillose.