rhizomes long- to short-creeping, ascending, suberect, or erect, bearing scales (less often, only hairs); blades monomorphic, hemidimorphic, or dimorphic in a few genera, simple (mostly vittarioids), pinnate, or sometimes pedate, sometimes decompound; veins free and forking, or variously anastomosing and forming a reticulate pattern without included veinlets; sori marginal or intramarginal, lacking a true indusium, often protected by the reflexed segment margin, or sporangia along the veins; sporangia each with a vertical, interrupted annulus, receptacles not or only obscurely raised; spores globose or tetrahedral, trilete, variously ornamented; mostly x = 29, 30.
Distribution
Terrestrial, epipetric, or epiphytic, subcosmopolitan, but most numerous in tropics and arid regions.
