Blechnum - Blechnaceae

Blechnum australe L. ssp. australe

Photo: P. Ballings
South Africa

Photo: JE. Burrows
South Africa

Photo: JE. Burrows
Zimbabwe

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

Photo: P. Ballings
South Africa

 

 

 

 

Synonyms

Blechnum australe L. var. aberrans N.C.Anthony & Schelpe
Lomaria australis (L.) Link
Mesothema australe (L.) C.Presl
Spicanta australis (L.) Kuntze
Lomaria pumila Kaulf.
Blechnopteris australis (L.) Trevisan
Struthiopteris australis (L.) Trevisan

Common name

Description

Rhizome thin (3-20 mm), creeping widely, ending in a thickened, erect portion; rhizome scales dark brown, ovate-lanceolate in outline, apex tapering to a point, 2-10 x 0.2-2 mm, margins entire. Fronds tufted, dimorphic. Stipe 2-20 cm long, pale brown and glabrous at maturity but with scales similar to the rhizome at the base. Sterile lamina (6-) 28-56 cm × (1-)3.5-13 cm, pinnate with reduced basal pinnae and narrowly elliptic in outline; pinnae lanceolate, joined to the rhachis at least basally, glabrous or thinly grandular, margin entire to minutely serrate, apex mucronate. Fertile lamina same size or somewhat longer than the sterile lamina; pinnae linear, with the bases remaining lobed, basal pinnae often not fertile. Sori linear, limited to the middle part of the fertile lamina; indusium continuous, erose or lacerate, 0.3-0.8 mm wide.

Notes

B. australe can be distinguished from B. punctulatum by fertile fronds that are generaly longer than sterile ones, sori that are present only in the central pinna region and the adnate to sessile base of the pinnae in the sterile lamina. B. australe also has sharply pointed mucronate pinnae tips.

Derivation

australe: southern, of the south (botanists thought this fern to be limited to the southern areas of Africa).

Habitat

Terrestrial in forest margins or lithophyte in rock crevices or at base of boulders along mountain streams, sun or shade.

Distribution worldwide

Africa, Madagascar, Tristan da Cuñha, Gough and Ascension Islands.

Distribution in Africa

Kenya, Lesotho, Malawi, Namibia, South Africa, Swaziland, Tanzania , Zimbabwe, Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 335 - 336. (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 742 - 743. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 469 - 471. (Includes a picture).
  • Parris, B.S. (2006) Blechnaceae. Flora of Tropical East Africa, Royal botanic Garden, Kew. Pages 5 - 6. (Includes a picture).
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 154.
  • 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 102.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta. Flora Zambesiaca, 0 Page 240.
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