5. Atractylocarpus Mitt. 长帽藓属 chang-mao xian shu
J. Linn. Soc. Bot. 12: 71. 1869, nom. cons. Metzleria Schimp. ex Mild., Bryol. Siles. p. 75. 1869, nom. rejic. Metzleriella Limpr., Laubm. Deutschl. 1: 411. 1887, nom. inval. prov. Metzlera Schimp. ex Hag., Kongel. Norske Vidensk. Selsk. Skr., 1910(3): 15. 1910. Metzlerella Hag., Kongel. Norske Vidensk. Selsk. Skr., 1914(1): 62. 1915.
Plants small, slender to large, usually less than 2 cm high, sometimes up to 5 cm high, dull, yellowish green, glossy, in loose or compact tufts. Stems erect, simple or sparsely branched, radiculose nearly to the apex; central strand present. Leaves erect-spreading or slightly falcate-secund, narrowly ovate-lanceolate at base, subulate to tubulosely setaceous above; margins entire or only serrulate near the apex, often recurved; costa single, broad, flattened, 1/2 – 2/3 the leaf base width, filling most of leaf subula, in cross section with 2 stereid bands and a median row of guide cells; marginal borders consisting of linear cells; upper cells linear, thick-walled; lower cells rectangular, thin- to thick-walled; alar cells not differentiated. Autoicous or dioicous. Perigonia with a short stalk. Perichaetial leaves convolute-sheathing, abruptly subulate. Setae elongate, straight; capsules erect, symmetric or sometimes slightly curved, narrowly oblong-cylindric; annuli none or large, deciduous; opercula long-rostrate; peristome teeth divided nearly to the base, coarsely papillose above, diagonally or vertically striate below. Calyptrae cucullate, somewhat inflated, entire at base, smooth. Spores spherical.