Very small to medium-sized ferns; epiphytic, lithophytic or rarely terrestrial. Rhizome short- or long-creeping or climbing, laterally branched; roots formed ventrally, dorsally with 2 rows of frond scars. Fronds mono-, hemi- or dimorphic, articulated or not; stipe short or long; lamina simple to 2-pinnatifid, entire or shallowly crenate; veins free or anastomosing. Indumentum composed of scales on the rhizome, axes and lamina and hairs on the lamina surfaces. Sori circular (in ours), superficial or slightly sunken, scattered or in a single row on either side of the primary or secondary vein, with or without paraphyses; exindusiate.