Subshrubs or perennial herbs, erect or decumbent. Young stems puberulent. Corolla pink or white with a purple, pink or less often yellow eye; tube pilose inside, throat villous. Stamens attached to the top of corolla‑tube, anthers oblong or oblong-lanceolate, seperate from stigma. . Ovary 1.9–3 mm. Follicles narrowly oblong, longitudinally grooved, apex acute. Exotic species originated from East Africa and Madagascar.