Dryopteris - Dryopteridaceae

Dryopteris lewalleana Pic.Serm.

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

 

 

 

 

Synonyms

Lastrea pentagona T.Moore
Aspidium pentagonum (T.Moore) Kuhn
Dryopteris inaequalis (Schltdl.) var. atropaleacea Schelpe

Common name

Description

Rhizome shortly-creeping, becoming erect at the growing tip, up to 160 × 25 mm; rhizome scales straw- to rust-coloured, ovate to linear-acuminate, up to 18 × 4 mm, margins entire or with a few outgrowths, apex thread-like. Fronds tufted to spaced at rhizome apex, suberect to arching, up to 1.35 m long, herbaceous. Stipe up to 67 cm long, pale brown to greenish above, chestnut-coloured below, with straw- to rust-coloured scales, ovate to narrowly lanceolate, up to 25 × 6 mm, denser near the base. Lamina up to 73 × 64 cm, ovate to deltate in outline, 3-pinnatifid to 3-pinnate, up to 14 pairs of pinnae, spaced below and somewhat overlapping near the lamina apex. Pinnae up to 32 × 25 cm, forming an angle of 70-80° from the rhachis, usually not reduced and basiscopically developed, basal pair inequilaterally triangular to deltate in outline. Pinnules: acroscopic pinnule smaller than basiscopic pinnule on basal pinnae; ultimate segments narrowly ovate-obtuse to oblong-obtuse, shallowly to deeply lobed, margins serrate, glabrous on both surfaces but with a few minute hairs and scales along the costules and costae, costules narrowly winged for most of the length. Rhachis straw-coloured with a few straw-to rust-coloured scales similar to but smaller than those on the stipe, narrowly winged towards the apex. Sori round, c. 1.6 mm in diameter, medial on the veins; indusia kidney-shaped, entire, persistent, brown, up to 1.6 mm in diameter, glabrous.

Notes

Could be confused with Dryopteris pentheri which has basal pinnae inequilaterally ovate, with the basal basiscopic pinnule shorter than the 2 or 3 adjacent pinnules and narrowly lanceolate to filiform stipe scales.

Derivation

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

Habitat

Seasonally moist conditions among rocks, along streams in evergreen forests, riverine forests, hillside thickets, woodland.

Distribution worldwide

See African distribution.

Distribution in Africa

Burundi, Dem. Republic of Congo, Ethiopia, Kenya, Malawi, Mozambique, South Africa, Swaziland, Tanzania , Uganda, Zambia, Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Pages 476 - 477. (Includes a picture).
  • Kornas, J. (1979) Distribution and ecology of the Pteridophytes in Zambia. Polska Akademia Nauk Wydzial II Nauk Biologicznych. Page 108. As Dryopteris inaequalis var. atropaleaceae
  • 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 122.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta.Southern African Botanical Diversity Network Report, 13 Page 125.
  • Roux, J.P. (2012) A revision of the fern genus Dryopteris (Dryopteridaceae) in sub-Saharan Africa.Phytotaxa, 70(1) Pages 69 - 76. (Includes a picture).
  • Roux, J.P.; Shaffer-Fehre, M. & Verdcourt, B. (2007) Dryopteridaceae.Flora of Tropical East Africa, Pages 42 - 43.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta.Flora Zambesiaca, 0 Page 222. As Dryopteris inaequalis var. atropaleacea
  •