Cyptodon

Tufts on rocks, branches or roots that are periodically submerged. Secondary stems differentiated into a short basal stipe section and a usually much longer pinnately branched frond section, with rhizoids restricted to base. Leaves ovate to elliptic, spreading when moist, imbricate and appressed to erect-patent when dry, decurrent; apex acute to obtuse; costae single, subpercurrent; margin serrulate toward apex, otherwise entire, recurved, without a border; laminal cells rhomboid to elliptic or hexagonal, becoming linear at base, smooth; alar cells not differentiated. Perichaetia terminal on branches. Capsules immersed, straight, broadly cylindric, without an annulus. Calyptra mitrate. Operculum flat and apiculate. Peristome double; exostome horizontal when moist; endostome segments as long as exostome teeth, with a low basal membrane.