Polystichum volkensii (Hieron.) C.Chr.
Synonyms |
Aspidium volkensii Hieron. |
---|---|
Common name |
|
Description |
Rhizome short, erect, up to 1 cm in diameter; rhizome scales persistent, papery, reddish, narrowly lanceolate in outline, up to 15 mm long. Fronds tufted, up to 8 per plant, erect, up to 120 cm long, herbaceous, gemmiferous. Stipe reddish-brown at base, straw-coloured above, up to 10–52 cm long, to 1 cm in diameter, upper surface grooved, stipe bases persistent, with dense reddish translucent shortly stalked scales, the larger elliptic to ovate, up to 34 x 10 mm, the smaller convolute, ovate. Lamina upper surface olive green, lower surface pale green, narrowly ovate in outline, up to 93 cm long, 3-pinnate. Pinnae oblong-attenuate, slightly falcate, basal pinnae up to 54 mm long, middle pinnae to 190 x 40 mm, lowest acroscopic pinnule slightly enlarged, a single pair of basal pinnae decrescent, often somewhat deflexed. Pinnules asymmetric, wedge-shaped, ovate, up to 23 x 11 mm, acroscopic margin auriculate, deeply lobed, lobes oblong, serrate to crenate, upper surface with few folded, filiform scales up to 15 mm long, lower surface covered with red to reddish-brown papery folded filiform scales up to 16.5 mm long. Rhachis straw-coloured, upper surface grooved, with dense often folded scales up to 18 x 6 mm, smaller than, but resembling those of, the stipe, and with a single gemmiferous bud, covered in scales, near apex. Costa straw-coloured, upper surface with groove, scales dense, similar to but smaller than those on rhachis. Sori medial on unabbreviated vein branches, mostly in 1 row, discrete at maturity, in excess of 1 mm in diameter; indusium reddish to reddish-brown, peltate, circular, elliptic or without a clearly defined shape. |
Notes | |
Derivation | volkensii: after G.L.A. Volkens (1855-1917), German botanist and traveller, assistant of A. Engler at the Botanical Museum in Berlin, Curator of the Botanical Gardens in Berlin. |
Habitat | Upper moist forest zone, Hagenia zone, giant heath zone, 2800-3600 m. |
Distribution worldwide | See African distribution. |
Distribution in Africa |
|
Growth form |
Terrestrial. |
Literature |
|