Annual or perennials. Stem erect to procumbent or decumbent; diffuse. Leaves opposite or alternate. Flowers solitary axillary, red (or shades of it), blue, rarely white. Corolla rotate or funnel shaped, the lobes variously incised at the apex and fringed with glands or not. Pyxidium globose, operculate. Seeds many, angled, vesiculose.