Description from Flora of China
Herbs, small, erect, perennial, with cystoliths. Leaves petiolate; leaf blade margin entire to subsinuate. Inflorescences of axillary or terminal racemes, loose, when terminal sometimes branched and forming a panicle, pedicellate; bracts and bracteoles minute. Flowers 1(-3 or more) in only 1 axil per node. Calyx deeply 5-lobed; lobes subequal. Corolla white with colored markings on lower lip, broadly campanulate; tube short; limb slightly 2-liped; lower lip 3-lobed; upper lip 2-lobed; lobes ascending cochlear in bud. Stamens 2, included in to slightly emergent from corolla tube; anthers 2-thecous; thecae unequal, subparallel, ± equally to subequally inserted; staminodes 2, short. Ovary with 2 ovules per locule; stigma capitate to shallowly 2-lobed. Capsule with a solid stalk at base, fertile region ellipsoid, usually with a medial constriction, up to 4-seeded; retinacula present. Seeds ± discoid, surfaces and margin smooth to ± rugose, lacking trichomes.
Two species: E and S Asia; one species in China.
(Authors: Hu Jiaqi (胡嘉琪 Hu Chia-chi), Deng Yunfei (邓云飞); Thomas F. Daniel)