Pneumatopteris

Rhizome erect, often forming a short woody trunk, scaly. Lamina once pinnate with deeply lobed pinnae (almost 2-pinnate), basal pinnae gradually reduced in size, lowest ones much shorter than middle ones; pinnae lobes thin but with distinct cartilaginous edges; lamina never densely hairy; basal veins on adjacent lobes joining, the rest free. Sori round, in one row either side of midrib, away from pinna margins; indusium kidney-shaped or absent; sporangium with or without hairs near annulus, with elongate 3–4-celled hair on stalk of sporangium; spores with many small wings.