Origin of name:

marlothianum refers to the collector of the type specimen, H.W.R. Marloth (1855�1931), a German-born pharmacist who came to South Africa in 1883 and established himself as a remarkable botanist.

Diagnostic characters:

White bracts
Solitary or up to 3 heads grouped together
Herbaceous woolly plant

Description:

Bushy annual herb with a woody taproot, profusely branched from the base, stems up to 120 mm long, apparently decumbent then erect, much branched, cobwebby, leafy. Leaves up to 12 (�20) x 6 (�8) mm, elliptic, subacute, much narrowed to a petiole-like base, thickly greyish-white woolly. Heads homogamous, campanulate, 4�6 x 3 mm, solitary, or 2�3 at the tips of the branches and dwarf axillary branchlets, closely enveloped by surrounding leaves webbed together with wool. Involucral bracts in c. 3�5 series, subequal, loosely imbricate, tips acute to subacuminate, opaque milk-white, sometimes reddish above the stereome, exceeding the flowers, radiating. Receptacle very shortly honeycombed. Flowers 18�39, yellow, tipped reddish. Achenes 1 mm long, elliptic in outline, closely ribbed, with myxogenic duplex hairs. Pappus bristles many, equaling corolla, scabrid, bases nude, not cohering.

Flowering recorded in January, April and July.

Distribution:

Growing in sandy watercourses. Known only from a few collections, in the Namib desert, between the Kuiseb and Swartkop Rivers.

Desert Biome.

Notes:

Sometimes confused with H. herniarioides but more closely branched than that species with woollier leaves and heads borne singly or 2�3 together at the branch tips and on short axillary shoots. Also allied to H. roseo-niveum from which it is distinguished by its smaller heads, and to H. gariepinum, which generally has more flowers in the head, a few of them female. Some specimens may be difficult to place; more collections and field studies are needed.

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Taxonomy:

Literature:

Helichrysum marlothianum O.Hoffm. in Bot. Jb. 10:275 (1889); Moeser in Bot. Jb. 44: 304 (1910).

 

Type:

Namibia, Usakos, Hykamkab [Haigamkab], 400 m, April 1886, Marloth 1211 (BOL; K; NBG; PRE; SAM, iso.).

 

Synonym(s):

 

 

Vouchers:

Fock 8395 (M; PRE); Galpin & Pearson 7666 (K; PRE; SAM); Marloth 1477 (PRE).