3. Calliergon (Sull.) Kindb. 湿原藓属 shi yuan xian shu
Canad. Rec. Sci. 6(2): 72. 1894. Hypnum subgen. Calliergon (Sull.) Lesq. & James, Man. Mosses N. America 318. 1884. Hypnum sect. Calliergon Sull. in A. Gray, Manual (ed. 2) 672. 1856.
Sarmentypnum Tuom. & T. J. Kop., Ann. Bot. Fenn. 16: 223. 1979.
Plants medium-sized, large, or rather robust, green, yellowish green, or brownish red, slightly glossy, in loosely caespitose mats. Stems erect or prostrate, irregularly or regularly subpinnately branched; cortical cells small, thick-walled; pseudoparaphyllia large, foliose. Stem leaves ascending or imbricate, elongate-ovate, ovate, or nearly round, slightly concave, obtuse at apex; costae single, extending well beyond mid-leaf or nearly to leaf apex; median leaf cells linear; sometimes with short, hyaline, thin-walled (initial) cells near leaf apices, often with rhizoids densely distributed at the dorsal side; alar cells hyaline, large, inflated, usually auriculate. Autoicous or dioicous. Inner perichaetial leaves lanceolate, costae single. Setae slender, curved when dry, reddish or purple; capsules ascending or horizontal, elongate-ovoid or cylindrical, usually arcuate, mouth constricted when dry; annuli often absent or indistinctly differentiated; cilia 2–3, nodulose. Spores 12–18 µm in diameter, finely papillose.