Pityrogramma - Pteridaceae

Pityrogramma argentea (Willd.) Domin

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

 

 

 

 

Synonyms

Gymnogramma argentea (Willd.) Mett. ex Kuhn

Common name

Description

Rhizome short, c. 2 mm in diameter, erect to procumbent; rhizome scales linear attenuate, brown. Stipe up to 30 cm long, castaneous, glabrous with few scales near the base. Fronds tufted, arching, herbaceous. Lamina ovate-triangular in outline, up to 30×25 cm, 3- to 4- pinnatifid, basal pinnae basiscopically developed, upper surface green & glabrous, under surface covered with a yellow or white powder; ultimate pinnules deeply pinnatifid into rounded lobes, margins entire or shallowly lobed; veins free. Rhachis and secondary rhachis dark brown, shiny, occasionally with some patches of yellow or white powder. Sori linear, up to 2 mm long, exindusiate, along flabellate veins on secondary pinnules.

Notes

The yellow or white powder on the undersurface of the pinnae makes this fern easy to recognize.
P. calomelanos var. aureoflava also has yellow powder covering the lamina below; this species however is less divided (2- or 3-pinnatifid), more robust and the lamina is ovate to lanceolate in outline.

Derivation

argentea: silvery; refers to the white powder on the underside of the frond.

Habitat

In rock crevices and around boulders.

Distribution worldwide

Africa, Madagascar, Mauritius, Réunion.

Distribution in Africa

Angola, Malawi, Mozambique, South Africa, Zambia, Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 115 - 116. (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 312 - 313. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 221 - 222. (Includes a picture).
  • Kornas, J. (1979) Distribution and ecology of the Pteridophytes in Zambia. Polska Akademia Nauk Wydzial II Nauk Biologicznych. Page 61.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 57.
  • 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 177.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Pages 105 - 107. (Includes a picture).
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