Asplenium - Aspleniaceae

Asplenium protensum Schrad.

Photo: P. Ballings
Zimbabwe

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Zimbabwe

 

 

 

 

Synonyms

Asplenium protensum Schrad. var. pseudohorridum Hieron.

Common name

Description

Rhizome up to 5 mm diameter, erect or sometimes shortly creeping; rhizome scales dark brown with pale lacerate margings, narrowly ovate-triangular in outline, up to 2 mm long. Fronds tufted, arching, herbaceous, proliferous towards the apex. Stipe 4-18 cm long; stipe and rhachis are thinly pubescent and covered with few ovate brown scales. Lamina 15-95 × 3-12 cm, narrowly lanceolate in outline, 2-pinnatifid, lower pinnae reduced, apical pinnae linear and lobed. Pinnae in 24-56 pairs, 2-7 x 0.8-1.7 cm, lanceolate in outline, incised 2/3 of the way to the midrib, base unequal, acroscopic basal lobe well developed, thinly pubescent above and below; lobes oblique, truncate and bifid. Sori 10-22, linear, 2-6.5 mm long, set at about 15 degrees to the midrib; indusium entire, linear, membranous.

Notes

Differs from similar species by having proliferous fronds.

Derivation

protensum: extended, referring to the long, narrow fronds.

Habitat

Mostly on mossy boulders along deeply shaded streambanks in evergreen forest.

Distribution worldwide

Africa, Mascarene Isl.

Distribution in Africa

Angola, Burundi, Cameroon, Dem. Republic of Congo, Equatorial Guinea (incl. Bioko), Eritrea, Ethiopia, Kenya, Malawi, Mozambique, Nigeria, Rwanda, Somalia, South Africa, Sudan and South Sudan, Tanzania , Uganda, Zambia, Zimbabwe.

Growth form

Epiphytic, lithophytic, terrestrial.

Literature

  • Beentje, H.J. (2008) Aspleniaceae.Flora of Tropical East Africa, Pages 41 - 43. (Includes a picture).
  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Page 232. (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 620 - 621. (Includes a picture).
  • Fisher, E. & Lobin, W. (2023) Synoptic Revision of Aspleniaceae (Asplenium, Hymenasplenium) of Rwanda. Magnolia Press, New Zealand. Page 34.
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 354 - 355. (Includes a picture).
  • Kornas, J. (1979) Distribution and ecology of the Pteridophytes in Zambia. Polska Akademia Nauk Wydzial II Nauk Biologicznych. Pages 101 - 102.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta.Southern African Botanical Diversity Network Report, 13 Page 169. (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. Pages 94 - 95.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta.Flora Zambesiaca, 0 Page 179.
  • Tardieu-Blot, M.-L. (1964) Ptéridophytes vol.3.Flore du Cameroun, Pages 194 - 195. (Includes a picture).
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