E. melanthera is closely allied and similar in appearance to E. chamissonis. The chief differences between the two species are several. In E. chamissonis the leaves are quite different in appearance, being more or less open-backed and bearing long hairs, the peduncles and sepals are densely villous not merely pubescent and the anthers are not or scarcely produced beyond the pore. The two species occur in different areas which do not overlap and flower at different times of the year. In distribution E. melanthera is interesting in that it is confined to moist slopes along the entire length of the Langeberg and Outeniqua Mountains and on Swart berg Range further inland with records from the isolated mountains in the Little Karoo. In this respect it is an excellent example of the link between the floras of the moister southern mountains and the drier Swartberg Range.
Erect shrub up to about 6ocm (2 ft), sometimes more. Branches ascending or wide-spreading, pubescent. Leaves 3-nate, 2-4 mm long, spreading to squarrose, linear to oval, blunt, thick, sulcate, minutely tubercular-hispid, at length glossy. Flowers 3-nate, terminal, corolline, numerous; peduncles 2-4 mm long, pubescent; bracts variously placed, linear, small, sometimes larger and covering the calyx. Calyx about 2 mm long, obconic, 4-cleft, puberulous or glabrous, keeled or keel-tipped, coloured; lobes reniform or obcuneate, apiculate, more or less as long as the tube. Corolla 3.5-4.0 mm long, obconic, broad-cyathiform or funnel-shaped, dry, glabrous, pale or bright red; lobes continuous or spreading, broadly rounded, more or less equal to the tube in length. Filaments broadish; anthers included, about 1 mm long, lateral, obliquely oblong or semiovate, produced above into a contracted point about or nearly equal to the pore, scabrid, nearly black, muticous; 1/2-5/8 pore of the cell. Ovary turbinate, silky-villous, chiefly on top; style exserted; stigma minute, obconic or subsimple.