Pellaea - Sinopteridaceae

Pellaea calomelanos (Sw.) Link var. swynnertoniana (Sim) Schelpe

Photo: BT. Wursten
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

Photo: P. Ballings
Mozambique

 

 

 

 

Synonyms

Pellaea swynnertoniana Sim

Common name

Blue rock fern Mumvuriwedombo

Description

Rhizome erect to shortly creeping, c. 6 mm in diameter; rhizome scales linear-lanceolate in outline, apex slowly tapering to a point, margins pale, up to 10 mm long, black. Fronds monomorphic, tufted, erect to arching, usually more than 40 cm tall, coriaceous. Stipe 5-30 cm long, round, black, very shining, hairless or finely set with orange-brown short hairs on the upper surface, sometimes with a few scales similar to the rhizome scales near the base, old stipe bases present. Lamina mostly 2-pinnate, occasionally 3-pinnate on the lower pinnae, ovate -lanceolate to narrowly triangular in outline, 10-43 × 2.5-25 cm; pinnae 7-12 pairs, opposite to slightly alternate, oblong-ovate in outline, 1.5-6 cm long; pinnules more than 2 cm long, rounded to broadly hastate, with 3-5 acute to rounded points, articulated, petiolate, grey to bluish green above, paler below, hairless; venetion free, hardly visible; rhachis and secondary rhachis shiny black, hairless or finely set with orange-brown short hairs on the upper surface. Sori borne in a continuous ridge along the margins, indusium continuous, entire, membranous.

Notes

The rounded to broadly hastate pinnules, with typically 3-5 acute to rounded points, a grey-green colour and thick texture make this species easy to recognize. Could be confused with P. calomelanos var. calomelanos which has smaller fronds, pinnules that are less than 2 cm long and is more common.

Derivation

kalos: pretty, melanos: dark; alluding to the glossy black stipe and rhachis of the plant. swynnertoniana: named after C.F.M. Swynnerton (1877-1938), well known collector & forester at Mt. Selinda.

Habitat

High altitude Brachystegia spiciformis woodland on granite or quartzite outcrops, in Uapaca kirkii woodland on heavier soils, in areas with frequent mist and high rainfall.

Distribution worldwide

Distribution in Africa

Malawi, Mozambique, Tanzania , Zimbabwe.

Growth form

Lithophytic, terrestrial.

Literature

  • Burrows, J.E. (1990) Southern African Ferns and Fern Allies. Frandsen, Sandton. Pages 176 - 177. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 278 - 279. (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 189.
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta.Southern African Botanical Diversity Network Report, 13 Page 71.
  • Schelpe, E.A.C.L.E. (1970) Pteridophyta.Flora Zambesiaca, 0 Pages 132 - 133. (Includes a picture).
  • Verdcourt, B. (2002) Adiantaceae.Flora of Tropical East Africa, Page 17. Note under Pellaea calomelanos var. calomelanos.
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