Common Name: CACTUS FAMILY
Habit: Perennial herb, shrub, tree, generally fleshy. Stem: cylindric to spheric, or flat; surface smooth, tubercled, or ribbed (grooved); nodal areoles bearing flowers. Leaf: generally 0 or early-deciduous, flat to +- cylindric. Spines: areoles generally with central, radial spines, occasionally with glochids. Flower: generally 1 per areole, bisexual [unisexual], sessile, radial [bilateral]; perianth parts generally many [5], scale-like to petal-like; stamens many; ovary inferior [superior], style 1, stigma lobes generally several [many]. Fruit: dry to fleshy or juicy, indehiscent to variously dehiscent, spiny, scaly, or naked; tubercled or smooth. Seed: generally many, occasionally 0--few.
Genera In Family: +- 125 genera, +- 1800 species: America (especially deserts), Africa; many cultivated, some edible. Note: Spines smaller, fewer (0) in shade forms; yellow spines blacken in age. Introduced species increasingly escape cultivation. Hybridization common in some genera.
eFlora Treatment Author: Bruce D. Parfitt, except as noted
Scientific Editor: Bruce D. Parfitt, Douglas H. Goldman, Bruce G. Baldwin, Thomas J. Rosatti.

Common Name: CHOLLA
Habit: Shrub or small tree, erect to decumbent, many-branched. Stem: regularly segmented, segments generally < 50 cm, < 5 cm diam, cylindric, fleshy, glabrous; ribs generally 0; tubercles generally elongate. Leaf: conic to cylindric, deciduous. Spines: 1--many per areole, < 2 mm diam, generally needle-shaped, smooth, straight, tip smooth or barbed, epidermis separating as a papery sheath; central spines generally not distinct from radial spines; glochids generally numerous in each areole. Flower: lateral to terminal, from distal portion of areole, 1.8--8 cm diam; perianth yellow, yellow-green, orange-yellow, to bronze, pink, or red; ovary glabrous, spines 0--many, glochids many in each areole, scales 0. Fruit: indehiscent; spheric or cylindric to obconic, dry or fleshy to leathery in age, green to dark yellow, glabrous, spiny or spines 0. Seed: 1.9--7 mm, flattened to +- spheric, surface smooth to angular, within an aril, bony and +- white when dry.
Etymology: (Cylindric Opuntia) Note: Hybridization common. Young buds of some species used for food, many species for ornament. Cylindropuntia chuckwallensis newly described, added as native.
eFlora Treatment Author: Marc Baker, Bruce D. Parfitt & Jon Rebman
Reference: Baker & Cloud-Hughes 2014 Madroño 61:231--243; Mayer et al. 2011 Madroño 58:106--112
Unabridged Reference: Pinkava 2002 Succ Pl Res 6:59--98; Rebman & Pinkava 2001 Florida Entomol 84:474--483