Asplenium - Aspleniaceae

Asplenium tenuicaudatum Pic.Serm.

 

 

 

 

Synonyms

Common name

Description

Rhizome erect short, densely set with scales; rhizome scales narrowly triangular, but with two large auricles, slightly superposed, forming a subcircular basal part, base cordate-attached, margin entire, but with auricles loosely fringed, ending in short hair, including the auricles 4–5 x 0.7–1.1 mm, heterogeneous texture; auricles in the marginal zone with thin cell walls, chestnut, in the middle part ribbed: ribs with thickened cellular walls, joining together above the point of scale insertion into a single rib, the whole width and length of the remaining scale part, with exception of the terminal hair,thick, rigid, dark brown, strongly thickened cellular walls concealing light. Fronds monomorphic, numerous, tufted, erect-spreading, 28-36 cm long, not proliferous. Stipe rounded at the base, slightly channeled upwards, 12-16 cm long x 0.7-1 mm in diameter, bright chestnut, sparsely scaly, scales similar to rhizome scales, but less thickened. Lamina pinnate, ovate in outline, 16-20 x 8-10 cm; pinnae 2-4 jugate, narrowly stipillate, very variable in form, clearly unequal, narrowly dimidiate-lanceolate, narrowly dimidiate-trullate or long trullate, base long cuneate, upwards unevenly lobed abruptly constricted in a very long slender tail, apical margin serrulate, 6-7.5 x 0.5-1 cm, texture papery, above glabrous, below sparsely scaly, scales thick, with thickened cell walls, ovate-lanceolate, tailed at the apex, sometimes fringed at the base, up to 1 mm long, apical pinna more or less unequally tricuspidate; rhachis channeled, lightly chestnut, shiny, glabrous. Sori linear, tapering off on both sides, up to 15 x 0.8 mm; indusium entire membranous.

Notes

Differs from A. megalura by the pinnae narrower, narrowly dimidiate-lanceolate to long trullate, with a base long cuneate, spread out upwards, unequally lobulate and abruptly narrowed into a very long slender tail, by the frond ovate in outline with 2-4 pairs of pinnae only, by the stipe and rhachis slenderer , and by the shape , size and structure of the scales.

Derivation

tenuidaudatum: hinting at the shape of the pinnae which are provided with a very long slender tail.

Habitat

Epiphyte in forest, c. 2500m

Distribution worldwide

See African distribution.

Distribution in Africa

Dem. Republic of Congo, Rwanda.

Growth form

Epiphytic.

Literature

  • Pichi Sermolli, R.E.G. (1977) Fragmenta Pteridologiae VII. Webbia, 32 (1) Pages 85 - 87. (Includes a picture).
  • Roux, J.P. (2001) Conspectus of Southern African Pteridophyta. Southern African Botanical Diversity Network Report, 13 Page 98.
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