Cactoidea is the largest subfamily of the Cactaceae. The cactus family, Cactaceae, is comprised of thousands of species characterized by having thick, fleshy stems. They are often found thriving in hot, arid habitats. They are able to survive in these places due to their morphological and physiological adaptations in conserving water. Cactoidea is comprised of nine tribes: (1) Browningieae, (2) Cacteae, (3) Calymmantheae, (4) Cereeae, (5) Hylocereeae, (6) Notocacteae, (7) Pachycereeae, (8) Rhipsalideae, and (9) Trichocereeae
Cacteae is a large tribe of Cactoidea. They comprise nearly 75% of all Cactaceae. Its members are characterized mainly by their stems that resemble leaves. Some of them may have scales that resemble leaves as well.
Cacteae is further divided into sub-tribes: Cactanae (includes the genera Discocactus and Melocactus), Cactinae (includes the genera Coryphantha and Mamillaria), Cereinae (includes the genera Cephalocereus, Cereus, Cleistocactus, Espostoa, and Oreocereus), Echinocactinae (includes the genera Echinocactus, Ferocactus, Gymnocalycium, and Parodia), Echinocereinae (e.g. Echinocereus and Echinopsis genera), Epiphyllinae (e.g. Epiphyllum and Schlumbergera), Hylocereinae (e.g. Hylocereus), and Rhipsalidinae (e.g. Lepismium).
- Kingdom: Plantae
- Order: Caryophyllales
- Family: Cactaceae
- Subfamily: Cactoideae
- Tribe: Cacteae