Cordylostigma longifolium (Klotzsch) Groeninckx & Dessein

longifolia: with long leaves.

Erect to somewhat straggling or decumbent annual or perennial herb, up to c. 1 m tall. Stems somewhat quadrangular and woody near the base, mostly hairless or sparsely pubescent on the ribs but becoming more densely hairy towards the top. Leaves opposite, linear to linear-lanceolate, up to 9.5 cm long, hairless or somewhat roughly pubescent; margin often rolled under. Flowers in more or less lax branched heads. Corolla 4-lobed, from bright red to various shades of purple, pink, blue or white above, paler, beneath; tube 2.5 - 7 mm long, greenish.

Northern Somalia, southeastern Kenya, Tanzania, DRC, Mozambique, Malawi, Zambia, Zimbabwe and Madagascar.