4. Lopidium Hook. f. & Wils. 雀尾藓属 que-wei xian shu
Fl. Nov.-Zel. 2: 119. 1854.
Plants slender, creeping. Secondary stems erect, simple or regularly pinnately branched, yellowish green or dark green, not glossy; central strand absent. Lateral leaves ovate-ligulate, asymmetric, mostly obtuse, mucronate at apex; costa stout, ending below the apex; lamina cells small, oval or rounded, markedly mammillose or unipapillose, walls incrassate, collenchymatous; amphigastria small, triangular or ovate-lanceolate, symmetric, long acuminate toward apex, margins nearly entire. Monoicous or autoicous. Inner perichaetial leaves long, gradually narrowly acuminate at apex, with oblong leaf base, margins nearly entire; costa strong, ending near leaf apex or almost percurrent; leaf cells hexagonal, walls incrassate, porose. Setae short, finely papillose above; capsules small, erect or slightly suberect; annuli absent; peristome double; exostome teeth narrowly lanceolate, papillose above, densely striate below; endostome segments narrowly elongate; basal membrane low; cilia absent. Calyptrae small, cucullate. Spores small, minutely papillose.