Dryopteris - Dryopteridaceae

Dryopteris inaequalis (Schltdl.) Kuntze

 

 

 

 

Synonyms

Aspidium inaequale Schltdl.
Dryopteris elongata sensu Sim
Lastrea inaequalis (Schltdl.) C.Presl.
Nephrodium filix-mas (L.) Rich. var. elongatum sensu Sim
Nephrodium inaequale (Schltdl.) Hook., non Schrad.

Common name

Description

Rhizome short-creeping, branched, up to 160 x 14 mm; rhizome scales straw to rust-coloured, ovate to linear in outline, apex filiform, margins entire or with a few scattered outgrowths. Fronds mostly 2-4, erect to arching, closely to widely spaced, herbaceous. Stipe up to 67 cm long, 7 mm in diameter, strawcoloured to greenish above, chestnut coloured below; scales ovate to narrowly lanceolate to filiform in outline, straw to rust-coloured, up to 45 x 9 mm. Lamina up to 73 x 56 cm, deltate to ovate in outline, 3-pinnate to 3-pinnatifid, with up to 14 pinnae pairs, basaly widely spaced, somewhat overlapping towards the lamina apex. Pinnae basal pair inequilaterally triangular to broadly ovate or deltate in outline, up to 28 x 18 mm, reduced and slightly basiscopically developed, set at 70-80° from the rhachis; costules narrowly winged for most of their lenght. Pinnules acroscopic pinnules on basal pinna up to 7.2 x 2.1 cm, basiscopic pinnule on basal pinna up to 11 x 3 cm. Ultimate segments ovate to oblong in outline, apices rounded, shallowly to deeply lobed, hairless on both surfaces but with scattered, minute hairs and scales along the costules and costae, margins serrate. Rhachis straw coloured, shallowly grooved, narrowly winged towards the apex, with scales similar to but smaller than those on the stipe. Sori round, discrete, up to 1.6 mm in diameter, medial on the veins; indusium reniform, margin entire or wavy, persistent, brown up to 1.6 mm in diameter, hairless or with glands on margin or surface.

Notes

Derivation

inaequalis: referring to the asymmetric basal pinnae of this species.

Habitat

Seasonally moist coastal and montane forests, at the base of moist rock overhangs in grasslands.

Distribution worldwide

See African distribution.

Distribution in Africa

South Africa, Swaziland.

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 474 - 475. (Includes a picture).
  • Roux, J.P. (2012) A revision of the fern genus Dryopteris (Dryopteridaceae) in sub-Saharan Africa. Phytotaxa, 70(1) Pages 57 - 62. (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 122.
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