Asplenium - Aspleniaceae

Asplenium cordatum (Thunb.) Sw.

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Zimbabwe

 

 

 

 

Synonyms

Ceterach cordatum (Thunb.) Desv.
Gymnogramma cordata (Thunb.) Schltdl. var. namaquensis (Pappe & Rawson) Sim
Acrostichum cordatum Thunb.
Grammitis cordata (Thunb.) Sw.
Gymnogramma namaquensis Pappe & Rawson

Common name

Description

Rhizome erect or procumbent, 3-6 mm in diameter, scales dark brown, up to 4.5 mm long, lanceolate, tapering, margin paler. Fronds not proliferous, tufted, erect. Stipe short, up to 60 mm long, dark chestnut brown; scales shining, lanceolate, c. 3.5 mm. Lamina 2-15 × 1-5 cm, shallowly to deeply 2-pinnatifid, elliptic to oblanceolate in outline, subcoriaceous, inrolled when dry; basal pinnae gradually decrescent. Pinnae free, oblong-lanceolate, margins irregularly scalloped to incised, apex bluntly acute, base heart-shaped, undersurface very densely covered with pale reddish-brown scales. Rhachis not winged between pinnae; scales dark chestnut brown, lanceolate, 3mm long. Sori linear, up to 2 mm long, hardly visible because of the covering scales, exindusiate.

Notes

Until recently all Southern African ceterachoid aspleniums were treated as a single taxon displaying a lot of variation, now 2 other species are recognized: A. capense and A. phillipsianum. These are herbacious, with a less divided lamina, they have pinnae that are completely or partialy attached to the rachis, a rachis that is completely or partialy winged and sori that are much better visible because of sparse scale covering.
F.T.E.A does not agree with this split and still treats this as a single variable species. (Beentje, 2008)
Can also be confused with Mohria; A. cordatum has linear sori that are hardly visible through the scales.

Derivation

cordatum: heart-shaped, referring to the two basal lobes of the pinna.

Habitat

In a wide variety of habitats where it is often found in rock crevices or beneath boulders, sheltered from sun and wind. Terrestrial or lithophyte.

Distribution worldwide

See African distribution.

Distribution in Africa

Angola, Botswana, Kenya, Lesotho, Namibia, Somalia, South Africa, Tanzania , Uganda, Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Beentje, H.J. (2008) Aspleniaceae. Flora of Tropical East Africa, Page 71. Taxon is not split up but treated as a single variable species. (Includes a picture).
  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 255 - 256. (Includes a picture).
  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Pages 582 - 583. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 379 - 380.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 157.
  • Roux, J.P. (2009) Synopsis of the Lycopodiophyta and Pteridophyta of Africa, Madagascar and neighbouring islands. Strelitzia 23, South African National Biodiversity Institute, Pretoria. Pages 82 - 83.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Pages 188 - 189.
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