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Origin of name:
arenicola = a dweller of sand
Diagnostic characters:
Cartwheel like growth form
Heads surrounded by green woolly leaves
Small compact heads
Yellow bracts
Description:
Low-growing annual or short-lived (?) perennial with a long woody taproot, branches many from the crown, mostly 50�200 mm long, prostrate or suberect, slender, subsimple or much branched in upper half, thinly white-woolly, glabrescent, leafy. Leaves 4�13 x 1 (�2) mm, linear-oblong, narrowed in upper two thirds, obtuse, margins revolute, lower third broadened, half-clasping, margins flat, both surfaces glandular, thinly woolly-cobwebby, glabrescent. Heads homogamous, campanulate, c. 3 x 2 mm, several in tight clusters up to 10 mm diam, at the branch tips closely surrounded by reduced leaves and webbed to them with wool, old clusters overtopped by several younger flowering branchlets. Involucral bracts in 3 series, subequal, equaling flowers, not radiating, pellucid, yellow or straw-coloured, glossy, tips obtuse, erose, soon caducous. Receptacle with flattened tubercles. Flowers 16�28, yellow. Achenes 0,75 mm long, elliptic, glabrous or with myxogenic duplex hairs. Pappus bristles many, equaling corolla, scabrid, bases with patent cilia not cohering.
Probably flowers in any month, but most records are in spring (August to November) with others in December, February, March and May.
Distribution:
Grows in red Kalahari sands, on the slopes or in the depressions of dunes. Known from Gobabis, Sandfontein, Aminuis and Rehoboth districts in Namibia, Botswana, and the desert and semi-desert areas of the northern Cape and south-western Free State.
Savanna and Nama Karoo Biomes.
Taxonomy:
Literature:
Helichrysum arenicola M. D. Henderson in Mitt. bot. StSamml., M�nch. 5: 115 (1963); Merxm., F.S.W.A. 139: 92 (1967).
Type:
Kimberley distr., Zandbult, 20 miles NE. Douglas, Leistner 1551 (PRE, holo.).
Synonym(s):
H. rangei [Moeser ex] Dinter in Fedde, Repert. 18: 249 (1922), nomen nudum. Namibia, Aminuis, Range 779 (SAM).
Vouchers:
Acocks 18137 (PRE); Codd 5844 (PRE; WIND); Leistner 2904 (PRE); Wilman 1596 (SAM).