Family: Hypnaceae

Diagnosis: Plants small to robust, in loose or dense mats. Stems mostly creeping, sometimes ascending, irregularly branched to very regularly pinnate and sometimes frondose. Leaves of stems and branches mostly uniform, sometimes ± differentiated and ± asymmetric, often homomallous to secund or falcate-secund, occasionally somewhat complanate, various shapes, mostly ± long-acuminate; costa short and double or lacking; cells mostly linear, smooth (occasionally papillose because of projecting cell angles or very rarely with with several papillae in a row over the lumina at back), mostly differentiated at basal angles, usually small and quadrate but sometimes moderately enlarged and inflated in rather small but usually distinct alar groups. Setae elongate, mostly smooth; capsules erect or, more commonly, inclined to horizontal, ovoid to cylindric, straight or curved and asymmetric; annulus usually differentiated; operculum ± conic or sometimes convex, often rostrate; peristome double (or rarely the endostome lacking), typically well-developed and consisting of 16 lanceolate-subulate teeth with fine cross striolations on the outer surface. Calyptra cucullate, rarely ± hairy. Spores spherical.