Polystichum - Dryopteridaceae

Polystichum incongruum J.P. Roux

 

 

 

 

Synonyms

Common name

Description

Rhizome decumbent, stout, up to 16 mm diameter, sparsely branched; rhizome scales chestnut to reddish brown. Fronds closely spaced, arching. Stipe up to 93 cm, straw-coloured above, chestnut at the base, set with rediish brown to straw-coloured scales, scales up to 20 mm long, ovate in outline, apex tapering to a point. Lamina up to 87 cm long, ovate in outline, 2- or 3-pinnate, basal pair of pinnae sometimes reduced. Pinnules asymmetrically ovate, with a basal acroscopic lobe, slightly falcate, venation more obviously below, sparsely set with a few, hair-like scales along the veins and costules above and below, margins serrate, sometimes doubly, seldom aristate. Rhachis moderately set with rust- to straw-coloured, narrowly triangular scales, up to 7 x 2 mm. Sori round; indusium c. 0.5 mm in diameter, entire, peltate, central portion often black.

Notes

Derivation

incongruum: incongruens meaning inconsistent, a reference to the variable lamina morphology of this species.

Habitat

Light shade along streambanks and forest clearings, forest floor, among boulders and at base of cliffs in upland grassland.

Distribution worldwide

See African distribution.

Distribution in Africa

South Africa.

Growth form

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 456 - 457. (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 137.
  •