Dryopteris - Dryopteridaceae

Dryopteris wallichiana (Spreng.) Hyl. ssp. reichsteinii Fraser-Jenk.

Photo: JE. Burrows
Zimbabwe

 

 

 

 

Synonyms

Common name

Description

Rhizome short, erect to suberect, forming a caudex of up to 16 × 8 cm; rhizome scales chestnut coloured, broadly attached, to 1.5 x 0.2 cm, cordate, margins with outgrowths. Fronds arising in a whorl, arching, firmly herbaceous, to 1.2 m long. Stipe up to 20 cm long, chestnut coloured at the base, paler higher up, densely covered with brown scales of 2 kinds. Lamina up to 1.2 × 0.38 m, narrowly oblanceolate to narrowly elliptic in outline, pinnate-pinnatifid to deeply bipinnatifid, with up to 47 pinna pairs, pinnae gradually reduced towards the base. Pinnae c. 20 × 2.5 cm, sessile to shortly stalked, set at 90° to the rhachis, narrowly oblong-attenuate, deeply pinnatifid; ultimate lobes rectangular, c. 16 × 7 mm, apices cut-off squarely, serrate, lateral margins subentire, glabrous but with few linear scales on the margins, costules and costae, venation evident on both surfaces. Rhachis densely covered with dark brown scales. Sori round, up to 12 per lobe, to 1.5 mm in diameter, inframedial on vein branches; indusium brown, entire, glabrous, kidney-shaped, to 1.5 mm in diameter.

Notes

This is a tall, bipinnatifid fern with distinctly cut-off square lobes, not to be confused with other species of Dryopteris.

Derivation

wallichiana: after N. Wallich (1786-1854), superintendent of the Calcuta Botanic Gardens in 1817; reichsteinii: after T. Reichstein (1897-1996), Nobel prize laureat in 1950, studying ferns after his retirement.

Habitat

Shaded ravine under Widdringtonia at c. 2100m.

Distribution worldwide

See African distribution.

Distribution in Africa

Zimbabwe.

Growth form

Terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 308 - 309. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 441 - 442. (Includes a picture).
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 124.
  • Roux, J.P. (2012) A revision of the fern genus Dryopteris (Dryopteridaceae) in sub-Saharan Africa. Phytotaxa, 70(1) Pages 108 - 110. (Includes a picture).
  • 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 124.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Page 225.
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