Annual or perennial herbs. Leaves exstipulate or with a pair of stipitate or sessile glands at base of petiole. Flowers solitary, axillary or terminal in simple racemes, subcorymbs or subumbles. The 2 lateral sepals small and greenish (in our species), the lower sepal petaloid with the spur usually well-developed, straight or curved. Anterior petal large, usually dorsally carinate. Lobes of lateral petal acute or obtuse. Capsule dehiscence septifragal, with the valves coiling up and inwards. Seeds glabrous or not.