木藓科 mu xian ke
by Wu Peng-cheng
Plants usually robust, sometimes medium-sized, rarely small, yellowish green or dark green, brownish green when old, slightly or not glossy, in loose tufts. Primary stems creeping, leaves deciduous, with reddish brown rhizoids; secondary stems dendroid, suberect or ascending, 1–2-pinnately branched above, or multiply branched; central strand scarcely to well differentiated. Stipe leaves scale-like, on the base of secondary stems; secondary stem and mature branch leaves similar, ovate or oblong-ovate, rarely broadly lingulate, mostly strongly concave, rarely plane, sometimes irregularly undulate, obtusely acute or acuminate at the apex; margins entire below, grossly serrate or serrulate above; costae single, usually thick, vanishing in leaf apex, sometimes with spines at the back; leaf cells hexagonal, oblong, or rhomboidal, evenly thick-walled, smooth; basal cells narrowly rectangular or oblong-rhomboidal; alar cells not clearly differentiated. Dioicous. Setae elongate, slender, smooth; capsules oblong-ovoid to subcylindrical; peristome teeth double; exostome teeth lanceolate; endostome segments linear-lanceolate, as long as the teeth; basal membrane high; cilia well developed, rudimentary, or absent. Calyptrae cucullate, not hairy. Spores spherical, finely papillose.