Diplazium australe (R.Br.) N.A.Wakef.

Rhizome erect, to 8 cm long, with dull dark brown to black scales. Fronds arcuate. Stipe 24–80 cm long, black and scaly at the base, deeply 3-grooved. Lamina 3-pinnate, 30–120 cm long, broadly triangular, 20–90 cm wide, membranous, brittle, dark green. Pinnules oblong, 5–25 mm long, 2–10 mm wide; base broadly attached to the axis; margins bluntly toothed or shallowly lobed less than half-way to the costule, decurrent on the lower side; apex obtuse. Sori 1–2 mm long, 3–5 per pinnule, mostly single; indusium pale brown, fragile. See also Green (1994: 598–599).

Grows in moist shady gullies, wet sheltered slopes in open forest and in moist areas in rainforest. On Norfolk Island in similar habitats to D. assimile (Green 1994).