Blechnum - Blechnaceae

Blechnum punctulatum Sw. var. atherstonei (Pappe & Rawson) Sim

Photo: JE. Burrows
South Africa

 

 

 

 

Synonyms

Blechnum atherstonei Pappe & Rawson
Lomaria punctulatum (Sw.) Kunze var. atherstonei (Pappe & Rawson) Sim

Common name

Description

Rhizome creeping to suberect, up to 4 cm in diameter; rhizome scales dark brown, linear, up to 2 cm long, margins pale, entire. Fronds dimorphic, tufted. Stipe up to 10 cm long, glabrous but with scales towards the base. Sterile lamina up to 110 cm × 15 cm, linear-elliptic in outline, pinnate with basal pinnae gradually decrescent; pinnae narrowly lanceolate, glabrous, margins entire, apex tapering to a point, sometimes falcate, base with truncate lobes overlapping the rhachis. Fertile lamina reduced; pinnae 1-4 mm wide, linear. Sori linear, set parallel to the costa, breaking into discrete, often oval segments, particularly towards the base; indusium linear, subentire, sometimes discrete.

Notes

All morphological features of this variety are similar to var. punctulatum, but it differs by its interrupted sori and broader (7-12mm) fertile pinnae (Jacobson.1983)

Derivation

athersonei: named after W.G. Atherstone (1814-1898), medical practitioner, geologist and naturalist.

Habitat

Evergreen forest margins, steep mountain slopes, shaded forest floors, mist-belt scrub.

Distribution worldwide

See African distribution.

Distribution in Africa

Malawi, South Africa, Swaziland.

Growth form

Terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Page 334.
  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Page 738. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 467 - 468. (Includes a picture).
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 155.
  • 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 104.
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