Herbs or shrubs. Stems modified into cladodes, succulent, ± spiny. Small leaves may be present on new growth. Areoles present from which spines, hairs, flowers and cladodes develop. Flowers bisexual, usually solitary, short lived. Hypanthuim elongated to cup-shaped. Perianth segments numerous and showy. Stamens numerous. Ovary inferior, 1-locule. Style simple, 3-many stigmas. Fruit a fleshy berry. 100 gen., temp. and subtrop. America