Plants small, in wiry wefts, prostrate mats, or threadlike, dark or olive green to yellowish. Stems erect to ± creeping, freely and irregularly branched to subpinnate; paraphyllia few or absent; pseudoparaphyllia foliose. Leaves erect to erect-spreading or occasionally squarrose, often homomallous, usually imbricate, concave, stem leaves often somewhat larger than branch leaves; margins entire, serrulate, or subentire; apex usually acuminate; ecostate or costa single, double, or 2-fid, short or to mid leaf; alar cells not or weakly differentiated; medial laminal cells quadrate, rhomboidal, or oblong-rhomboidal, smooth or papillose. Sexual condition dioicous. Capsule erect or horizontal, short-cylindric; operculum short-rostrate or conic, cucullate; peristome double.