Asplenium - Aspleniaceae

Asplenium variabile Hook.

Photo: C. Jongkind
Liberia

Photo: C. Jongkind
Liberia

Photo: P. Ballings
Uganda

Photo: P. Ballings
Uganda

Photo: P. Ballings
Uganda

 

 

 

 

Synonyms

Asplenium paucijugum Ballard
Asplenium variabile Hook. var. paucijugum (F.Ballard) Alston
Asplenium efulense Baker
Asplenium gautieri Hook.
Asplenium repandum Mett. ex Kühn
Asplenium dusenii Luerss. ex Bonap.

Common name

Description

Rhizome creeping or erect, 3–6 mm diameter; rhizome scales pale or dark brown, triangular or ovate in outline, apex gradually tapering to a point, clathrate, deciduous, 2–4 mm long, margins entire or sometimes (on same plant) with a few narrow teeth. Fronds shortly spaced or tufted, erect, slightly coriaceous, often proliferous at or near apex, occasionally proliferous at several pinnae apices. Stipe pale brown or green, once described as black with pale lines, 5–44 cm long, with scales similar to those of rhizome but soon glabrescent, often winged in the upper half. Lamina dark green, simple or imparipinnate with 1–2 pairs of (sub-)sessile subopposite pinnae, pinnae or lamina oblong-elliptic to lanceolate in outline, 4–22 x 1.5–6.5 cm, the terminal pinna slightly larger than the laterals, base slightly cordate to cuneate, margin wavy to lobed-toothed, apex tapering to a point, glabrous; veins forked, almost reaching the margin; rhachis similar to stipe. Sori many, evenly spaced and closely parallel along the oblique veins, reaching neither costa nor margin, 7–29 mm long; indusium membranous, linear, ± 0.3 mm wide, entire or with minutely fimbriate margin.

Notes

Tardieu distinguishes two varieties, var. variabile with simple leaves and var. paucijugum with pinnate leaves. These two varieties are now considered to be two accepted species A. variabile and A. paucijugum. I have to update!

Derivation

variabile: variable; Ballard in his protologue states that this taxon is “not so homogeneous a species as one might wish". (from F.T.E.A.)

Habitat

Moist forest, often along streams and waterfalls.

Distribution worldwide

Africa, Madagascar.

Distribution in Africa

Angola, Cameroon, Central African Republic, Dem. Republic of Congo, Equatorial Guinea (incl. Bioko), Gabon, Ghana, Guinea, Ivory Coast, Kenya, Liberia, Sierra Leone, Sudan and South Sudan, Tanzania , Uganda.

Growth form

Epiphytic, lithophytic, terrestrial.

Literature

  • Beentje, H.J. (2008) Aspleniaceae.Flora of Tropical East Africa, Pages 11 - 12. As Asplenium paucijugum Ballard (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 100.
  • Tardieu-Blot, M.-L. (1964) Ptéridophytes vol.3.Flore du Cameroun, Pages 182 - 185. (with 2 varieties) (Includes a picture).
  • Thardieu-Blot, M.L. (1964) Ptéridophytes vol.8.Flore du Gabon, Pages 123 - 125. (with 2 varieties) (Includes a picture).
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