Prostrate or scandent herbs with ± succulent stems and watery sap. Lvs usually alternate, sometimes opposite below, peltate or palmately lobed or compound, exstipulate; petiole coiling in climbing spp. Fls axillary, usually solitary, ☿, strongly zygomorphic. Calyx generally petaloid; sepals 5, free, the dorsal one produced as a spur. Petals usually 5, rarely fewer, imbricate, clawed, the upper 2 differently shaped, usually smaller. Stamens 8, free, declinate, unequal. Ovary superior, 3-celled, each cell with 1 ovule; placentation axile; style 1; stigmas 3. Fr. of 3, indehiscent, 1-seeded carpels eventually separate from central axis, very rarely winged, rarely baccate. Seed non-endospermic.