Perennial herb, with prostrate annual stems. Leaves opposite, ± succulent, variable. Flowers solitary, erect, borne on short pedicels. Corolla tube cylindric; limb spreading; lobes ± equal. Stamens 4. Fruit an extraordinary flattened woody capsule bearing two rows of curved arms which themselves bear recurved spines.
Derivation of name: "grapple", or "hook" plant
Worldwide: 2 species in southern Africa and Madagascar
Caprivi: 1 taxon.