Description from Flora of China
Trees. Leaves opposite, 2- or 3-pinnately compound; leaflets ovate, entire. Inflorescences cymose-paniculate, terminal. Calyx cupular, small, apex subtruncate, with very short teeth. Corolla bilabiate, tube long and narrow, upper lip 2-lobed, lower lip 3-lobed; lobes valvate, ovate-lanceolate, densely pubescent adaxially along margin. Stamens 4, didynamous, inserted high in corolla tube; 1 anther cell fertile and ellipsoid, another caudate and appendagelike. Disc annular-cupular. Ovary sessile, ovoid. Style long; stigma lingulate, compressed, 2-lobed, slightly exserted from corolla tube. Capsule dehiscing septicidally, long linear, compressed. Seeds in several rows, minute, compressed, winged.
One species: Cambodia, China, Laos, Myanmar, Thailand, Vietnam.