Herbs, erect, viscid pubescent throughout. Leaves opposite, broadly ovate, palmately veined. Inflorescences racemose, terminal and subterminal; bractlets 2, membranous, attached to calyx base. Calyx tube ventrally deeply incised; lobes unequal. Corolla campanulate, constricted at base; lobes unequal, rounded. Stamens 2; staminodes 2; anthers versatile. Capsule with thin, easily deciduous exocarp and woody, striate endocarp; horns short.

One species: Central America; naturalized in China.