Erect annual (sometimes biennial herb). Stem to 75 cm, square. Leaves opposite; lamina ± succulent, circular to ovate. Flowers solitary, yellow-green to white; corolla with a large basal spur. Stamens 4. Ovary 2-locular. Fruit indehiscent 4-winged.
Worldwide: 1 species in southern Africa: Botswana, Zimbabwe and S Africa