Herbs fleshy. Stems very short, branched or not. Flowers large, solitary or clustered at stem apex. Bractlets absent. Pedicel very long, erect. Calyx spathelike, apex acute or obtuse-rounded. Corolla tubular or campanulate, indistinctly bilabiate; upper lip 2-lobed; lower lip 3-lobed; lobes subrounded. Stamens 4, included; anthers adherent, 1 cell fertile, another reduced into a spur. Carpels 2; ovary usually 1-locular and parietal placentas 2 or 4, occasionally imperfectly 2-locular and placentas axile. Style slightly curved; stigma fleshy, peltate. Capsule dehiscing by 2 valves. Seeds numerous; testa reticulate.

About four species: Cambodia, China, India, Indonesia, Japan, Malaysia, Myanmar, Philippines, Sri Lanka, Thailand, Vietnam; three species in China.