Flowers: Perfect, often large and showy; actino-morphic to somewhat zygomorphic; gradual transition from sepals to petals, both numerous; carpels many; ovary inferior, sunken into stem tissue, 1-locular with many ovules; placentation parietal, sometimes a hypanthium present

Inflorescences: Solitary flowers emerging from areoles

Fruits: Berries surrounded by stem tissue; seeds with embryo coiled around perisperm

Habit: Stem succulents, perennials, some tree-like or epiphytic, spines produced from an AREOLE, which sometimes contains numerous GLOCHIDS; with betalain pigments; confined to the New World

Leaves: Reduced or absent except in Pereskia


Carnegia gigantea (saguaro)
Cereus (night-blooming cereus)
Echinocereus (barrel cactus)
Epiphyllum (orchid cactus)
Lophophora williamsii (peyote)
Mammillaria (pincushion cactus)
Opuntia (prickly pear, cholla)
Rhipsalis (wickerware cactus, mistletoe cactus, coral cactus, chain cactus, popcorn cactus)
Schlumbergera (Christmas cactus, Thanksgiving cactus)