Isoetes - Isoetaceae

Isoetes stellenbossiensis A.V. Duthie

Photo: JE. Burrows
South Africa






Common name


Pseudo-corm 3-lobed, harsh to touch; bud scales black, 3-toothed. Leaves 5-33, needle shaped, round in transverse section, 15-120 x 0.5-1 mm, flaring basally to form a wing up to 2 mm wide on either side of the sporangium. Ligule translucent, subulate to elongate-deltate, c. 2 mm long. Velum absent. Sporangia roughly oval, c. 2.5 x 2 mm. Megaspores 0.45-0.59 mm in diameter, white to greyish white when dry, shiny, distal surface clearly but shallowly reticulate, proximal surface reticulate but less regular and less clearly defined.



stellenbossiensis: this species was first found in Stellenbosch Flats in Western Cape.


Sandy soils in or around seasonally flooded depressions or pans, dying back in the dry summer.

Distribution worldwide

See African distribution.

Distribution in Africa

South Africa.

Growth form



  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Page 32. (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 58 - 59. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Page 156. (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 10.