Asplenium - Aspleniaceae

Asplenium burundense Pic. Serm.

 

 

 

 

Synonyms

Common name

Description

Rhizome erect; rhizome scales slender, triangular, apex very long tapering, hairy, arcuate-attached at the base, margin erose and fimbriae uncommon, 12-14 x 3-4 mm, membranous, light brown, heterotoechae (?), texture homogenous with small rectangular or trapezoidal cells, with thin walls. Fronds monomorphic, tufted, erect-spreading, up to 50 cm long, herbaceous. Stipe 9-14 x 0.1-0.15 cm, slightly channeled above, pale chestnut, in the middle part base slightly thickened, with scales when young becoming glabrous with age. Lamina pinnate, ovate in outline, twice as long as the stipe, 9-12 cm wide, brown-green when dry; pinnae 12-16 pairs, 4.5-6.5 x 0.9-1.1 cm, lower ones slightly shorter, upper ones gradually decreasing, apical pinnae distinct from the rest, equilateral, the lobes narrowly obovate-cuneate or oblong, bluntly tridenate or bidentate at the apex; lateral pinnae petiolate, narrowly triangular, sometimes narrowly triangular-lanceolate in outline, apex curved and tapering, base unequal, basiscopic side narrow cuneate, acroscopic side almost straight, pinnae lobes very oblique, notched or obtuse, first acroscopic lobe disjunct obovate-cuneate with a tri-quadridentate apex; rhachis below flat, finely glabrescent when young with scales similar to stipe. Sori inframedian, elliptic, c. 2.5 x 1.5 mm, thick; indusium inflated, persistent, margin intact, in proximal half papery green, in distal half membranous, yellow.
Translated from Latin, needs to be checked with specimens!

Notes

Differs from A. rukararense by the frond non-gemmiferous and smaller, by the pinnae much less subdivided, by the shape of the subdivisions of the pinnae and by the position of the sori. Differs from A. smedsii by the size and structure of the scales, by the shape, consistence and colour of the frond, by the shape and subdivision of the pinnae and by the position and size of the sori and the colour of their indusia.

Derivation

burundense: from Burundi, this fern was first discovered in the Bugarama mountains in burundi.

Habitat

Humid montane secondary forest.

Distribution worldwide

See african distribution.

Distribution in Africa

Burundi, Dem. Republic of Congo, Rwanda.

Growth form

Epiphytic.

Literature

  • Fisher, E. & Lobin, W. (2023) Synoptic Revision of Aspleniaceae (Asplenium, Hymenasplenium) of Rwanda. Magnolia Press, New Zealand. Page 10.
  • Pichi Sermolli, R.E.G. (1977) Fragmenta Pteridologiae VII.Webbia, 32 (1) Pages 78 - 80. (Includes a picture).
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta.Southern African Botanical Diversity Network Report, 13 Page 81.
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