Cheilanthes - Sinopteridaceae

Cheilanthes involuta (Sw.) Schelpe & N.C.Anthony var. involuta

 

 

 

 

Synonyms

Pteris involuta Sw.
Allosorus involutus (Sw.) C.Presl.
Pellaea virides (Forssk.) Prantl. var. involuta (Sw.) Schelpe
Pellaea involuta (Sw.) Bak. var. involuta
Cheilanthes involuta (Sw.) Schelpe & N.C.Anthony

Common name

Description

Rhizome creeping to ascending, c. 3 mm in diameter; rhizome scales linear-lanceolate in outline, apex gradually tapering to a point, margin entire, 3–6 mm long, pale reddish brown, sometimes with a dark central stripe. Fronds monomorphic, tufted, 10–40 cm long. Stipe 2–15.5 cm long, purplish black, grooved, sulcus rounded in cross-section, densely hairy and covered with brown or blackish scales up to 3 mm long. Lamina 2-pinnate to 3-pinnatifid, narrowly oblong to lanceolate in outline with the basal pinnae usually reduced, 3–24 x 2.2–13 cm; pinnae 4–12 pairs; ultimate pinnules oblong, oblong-ovate or oblong hastate in outline, 10–20 x 6–12 mm, with crimped edges, upper surface glabrous, costules below with a few scales; veins free, obscure or ± visible; rhachis and secondary rhachises set with numerous or scattered lanceolate brown hair-like scales, grooved above, sulcus rounded in cross-section. Sori marginal, linear; indusium continuous, suberose.

Notes

Differs from C. involuta var. obscura by having a more linear to lanceolate lamina, basal pinnae that are usually reduced and a sulcus that is round in cross-section.

Derivation

involuta: inrolled; refers to the sometimes inrolled pinnule margins.

Habitat

In dry areas on flat rock outcrops, around the base of boulders in grassland or dry scrub, in woodland, full sun or semi shade.

Distribution worldwide

Africa, Madagascar, Socotra.

Distribution in Africa

Angola, Burundi, Kenya, Rwanda, South Africa, Tanzania , Uganda.

Growth form

Lithophytic, terrestrial.

Literature

  • Crouch, N.R., Klopper, R.R., Burrows, J.E. & Burrows, S.M. (2011) Ferns of Southern Africa, A comprehensive guide. Struik Nature. Pages 384 - 385. (Includes a picture).
  • Jacobsen, W.B.G. (1983) The Ferns and Fern Allies of Southern Africa. Butterworths, Durban and Pretoria. Pages 287 - 288. As Pellaea viridis (Forsk.) Prantl. var. involuta (Sw.) Schelpe (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. Pages 182 - 183.
  • Verdcourt, B. (2002) Adiantaceae. Flora of Tropical East Africa, Pages 17 - 18. As Pellaea involuta (Sw.) Bak. var. involuta
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