They are the succulent plant family most rich in species (over 2,000 divided into 300 genera).
They come from America, they can be found from Canada to Patagonia, and are mainly concentrated in the desert and semi-desert areas of the south-western part of the United States, of Mexico and of the Andes. Some species have naturalized in the Mediterranean region, in Australia and Asia.
The trunk can be columnar, cylindric, spherical, articulated in segments (like in Opuntia), creeping or prostrated. The leaves are present only in the genus Pereskia; in most cases they are transformed into thorns.
Some species, like the Saguaro cactus (Carnegiea gigantea), can have huge dimensions (up to 20 meters of height).
Province: Imperia Region: Liguria