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Cacti

Cactaceae

Chollas, prickly pears, night-blooming cereus and their kin — the family that traded leaves for spines and turned its stems into reservoirs.

Acanthocereus

Cactaceae

Southern United States to northern South America

Slender, ribbed cereoid cacti that lean and clamber through the scrub. Their large white flowers open after dark and are finished by morning.

1 listing

Cylindropuntia

Chollas · Cactaceae

Southwestern United States and northern Mexico

Jointed, cylinder-stemmed cousins of the prickly pears, armored in papery-sheathed spines. Joints let go at a touch and root where they fall — the genus's way of walking across a desert.

2 listings

Opuntia

Prickly pears · Cactaceae

The Americas, from Canada to Patagonia

Flattened, paddle-shaped stems studded with glochids — tiny barbed bristles that deserve more respect than the spines.

1 listing

Quiabentia

Cactaceae

Eastern Brazil, Bolivia, Paraguay and northern Argentina

Leafy, shrubby opuntioids of South American dry forests, with fleshy leaves held in whorls along spiny stems.

1 listing