Description from Flora of China
Herbs, possibly perennial, terrestrial, rhizomatous. Stems usually simple. Leaves 1 to few, lowest leaf unpaired, those near apex usually opposite, equal or nearly so; leaf blade puberulent, base cordate. Inflorescences scorpioid, dense, pseudoterminal or axillary, many-flowered cymes; bract 1. Flowers zygomorphic, often reduced, cleistogamous, sometimes autogamous and intermediate. Calyx actinomorphic, 5-lobed from just above middle; segments equal. Corolla blue to reddish or white, zygomorphic, inside sparsely puberulent centrally or with a ring of hairs; tube tubular, not swollen, longer than limb, 2-3 mm in diam.; limb 2-lipped; adaxial lip 2-lobed, nearly equalling abaxial lip; abaxial lip 3-lobed, lobes subequal, apex rounded. Stamens 2, adnate to adaxial side of corolla tube above middle, included; anthers dorsifixed, apically coherent, thecae divaricate, confluent at apex, dehiscing longitudinally; connective not projecting; staminodes 2, adnate to abaxial side of corolla tube. Disc ringlike, cupular, interrupted, or 2-lobed. Ovary ovoid to globose, 1-loculed; placentas 2, parietal, projecting inward, 2-cleft. Stigma 1, terminal, subcapitate, undivided. Capsule straight in relation to pedicel, globose to subglobose, shorter than calyx, dehiscence circumscissile. Seeds with long deciduous funicle.
About 10 species: Africa, SE Asia; two species in China.