Annual (rarely perennial) succulent herbs, glaucous, glabrous. Leaves pinnately divided, variously lobed or toothed, or entire, succulent, upper leaves smaller. Inflorescence a raceme. Sepals erect; petals with claw c. 3–5 mm long, white, pink or purple; stamens 6; ovary sessile. Fruit indehiscent, corky, differentiated into 2 segments; stigma entire; lower segment various, usually 1-seeded; upper segment conical, sometimes flattened, 1-seeded, seed larger than that of lower segment.
7 species of the Northern Hemisphere, growing near fresh to saline water; 2 species naturalised in Australia.
Characterized by its fleshy, pinnately lobed leaves, fruit with a large terminal segment and the usually maritime habitat.