Pneumatopteris - Thelypteridaceae

Pneumatopteris usambarensis Holttum






Nephrodium truncatum sensu Peter, non (Poir.) Presl.

Common name


Rhizome shortly creeping or erect. Fronds monomorphic, tufted, 1–2 m tall. Stipe 30–45 cm long with small adpressed scales at base. Lamina simply pinnate, oblong in outline, 0.65–1.1 x 0.26-0.52 m, the lower 3 pairs, 5–8 mm long and 4 preceding pairs reduced; longest pinnae linear-oblong, 11.5–30 x 1.5–2.6 cm, apex long acuminate, with few hairs above, hairless beneath or rarely with few hairs, lobed 1/3–2/3 to costa; lobes semicircular to ovate-oblong, 2–7 x 4–4.5 mm, apex subtruncate to round, margin toothed or entire; veins 8–10 pairs, 2 basal pairs anastomosing. Indusia glabrous or slightly hairy, rarely conspicuously hairy; sporangia not setose.



usambarensis: named after the Usambara Mts. where this fern was first found.


Evergreen forest, 300-1500 m.

Distribution worldwide

See African distribution.

Distribution in Africa

Kenya, Tanzania .

Growth form



  • Roux, J.P. (2009) Synopsis of the Lycopodiophyta and Pteridophyta of Africa, Madagascar and neighbouring islands. Strelitzia 23, South African National Biodiversity Institute, Pretoria. Page 208.
  • Verdcourt, B (2006) Thelypteridaceae.Flora of Tropical East Africa, Page 35.