Terrestrial or epiphytic ferns with erect, creeping or climbing dictyostelic rhizomes, covered with scales. Leaves of diverse habit, simple to compound, heteromorphic to uniform; petioles with 1-2 vascular bundles, often scaly. Sori usually oblong to linear, borne either on one or on both sides of the vein, mostly with membranous, simple or double indusium. Spores bilateral.