Athyrium - Woodsiaceae

Athyrium lewalleanum Pic.Serm.






Common name


Rhizome long-creeping, slender; rhizome scales triangular in outline, apex gradually tapering to a point, base cordate, 0.2–1.2 mm long, 0.3–0.4 mm wide, pale brown or dark-marked, mixed with multicellular hairs. Fronds monomorphic, few, paired or solitary, 15–40 cm tall. Stipe 12–24.5 cm long, minutely pubescent or ± glabrous or with few scales at base. Lamina essentially trifid, the apical part pinnate with 12 or more pairs of pinnae, ± triangular-hastate in outline, 11.5–22 x 12–26 cm, with scattered flattened white multicellular hairs; pinnae lanceolate in outline, apex gradually tapering to a point, up to 5 x 1.8 cm, deeply pinnatifid with ± 10 pairs of pinnatifid segments about 2–7 mm wide; lateral parts similar to apical but with lowest basiscopic pinna well developed, up to 10 cm long; rhachis shortly pubescent. Sori 1–10 per segment, round, ± 1 mm in diameter; indusium sub-reniform, fixed on one side only, persistent or ± disintegrating and scarcely visible.



lewalleanum: type specimen was collected in Burundi by J. Lewalle, a Belgian botanist.


Evergreen forest along streams and rivers and on valley slopes, 900m.

Distribution worldwide

See African distribution.

Distribution in Africa

Burundi, 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 213.
  • Verdcourt, B. (2003) Woodsiaceae.Flora of Tropical East Africa, Page 12.