Pteris - Pteridaceae

Pteris cretica L.

Photo: P. Ballings
Zimbabwe

 

 

 

 

Synonyms

Pteris nervosa Thunb.
Pteris serraria Sw.
Pteris pentaphylla Willd.
Pteris cretica L. var. plurilobata Bonap.

Common name

Avery fern

Description

Rhizome shortly creeping; rhizome scales lanceolate, entire, dark brown, up to 3 mm long. Fronds tufted, up to 1.2m long, erect to arching, firmly herbaceous to coriaceous, dimorphous with the fertile fronds taller and with narrower pinnae than that of the sterile fronds. Stipe up to 60 cm in sterile fronds and up to 90 cm in fertile fronds, strawcoloured to brown and scaly at the base, glabrous. Sterile lamina 13-55 × 13-38 cm, ovate in outline, pinnate in the upper part, the lower part basiscopically developed, terminal pinnae larger or as long as the longest lateral pinnae; pinnae linear-lanceolate, apex tapering to a point, base cuneate, margins toothed, glabrous on both surfaces, veins free. Fertile lamina up to twice as large as the sterile lamina, pinnate with basal pinnae basiscopically developed; pinnae narrowly linear to narrowly lanceolate in outline, apex tapering to a point, base tapering, 7-13 mm wide, margin entire, glabrous on both surfaces. Sori linear, marginal, continuous, extending almost up to the apex; indusium membranous, entire.

Notes

Can only be confused with Lindsaea ensifolia which has a widely creeping, slender rhizome, anastomosing veins and pinnae with entire margins.

Derivation

cretica: from Crete; misleading as the species does not naturally occur on Crete.

Habitat

In shade in forest undergrowth, streambanks, shaded ravines, roadside embankments.

Distribution worldwide

Africa, Ascension I., Madagascar, Réunion and in Asia to Japan, and in southern Europe.

Distribution in Africa

Algeria, Angola, Burundi, Dem. Republic of Congo, Kenya, Lesotho, Malawi, Mozambique, Rwanda, South Africa, Swaziland, Tanzania , Uganda, Zambia, Zimbabwe.

Growth form

Terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Page 160. (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 318 - 319. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 236 - 237. (Includes a picture).
  • Kornas, J. (1979) Distribution and ecology of the Pteridophytes in Zambia. Polska Akademia Nauk Wydzial II Nauk Biologicznych. Page 68.
  • 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 171.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Pages 78 - 79. (Includes a picture).
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Pages 116 - 117.
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