Plants terrestrial or rarely on rock. Stems creeping to ascending or erect, slender to stout, sometimes climbing [rarely subarborescent]; scales brown or black. Leaves monomorphic or variously dimorphic, cespitose to scattered. Blades pinnatifid to 1-pinnate, rarely simple or 2-pinnate. Rachis and costae glabrous, scaly, or hairy abaxially. Veins free, often forked. Sori borne on vascular commissures parallel to costae, 1 per side, normally uninterrupted, linear, continuous along length of costa. Spores with perine smooth to variously winged or rugose. x = 28, 29, 31, 32, 34, 36.