Prostrate to scandent annual or perennial herbs or subshrubs. Leaves alternate, entire, petiolate or sessile, more or less succulent. Flowers solitary in axils or in axillary clusters of up to 5, sessile or shortly pedicellate; perianth of 1 whorl, of 4 or 5 segments; stamens 4–many, alternating with perianth segments or scattered; ovary inferior, 2–10-locular; ovules 1 per locule; styles equal in number to locules. Fruit indehiscent, dry or succulent with hard endocarp, ridged, winged or horned, sometimes papillose; seeds 1–several.
About 50 species, mostly Southern Hemisphere; 5 native in Australia, 2 or 3 naturalised.