Description from Flora of China
Shrubs, erect, deciduous. Winter buds with several pairs of scales. Leaves opposite, estipulate, shortly petiolate, slightly pubescent on veins and margin, margin entire or dentate at apex. Inflorescences of single flowers, paniculate; ovaries with 4 bracts at base; bracts unequal in size, larger 2 tightly adnate to ovary. Sepals 5, linear to lanceolate, ± fused at base. Corolla bilabiate, distinctly narrowed and gibbous at base; upper lip 2-lobed; lower lip 3-lobed. Stamens 4, didynamous, partially adnate to corolla tube, included. Ovary 4-locular, 2 locules with 2 series of sterile ovules, 2 locules each with a single fertile ovule; style slightly shorter than corolla. Fruit an achene with 2 accrescent, membranous, winglike bracts at base, crowned with persistent calyx.
● Three species: China.