Arthrocereus

Arthrocereus is a genus of cactus, native to southeast and west-central Brazil.

==Description== The relatively small, bushy, erect or prostrate species of the genus Arthrocereus are branched or unbranched. The articulated, cylindrical shoots have 10 to 18 low and narrow ribs on which small areoles sit from which many thin thorns emerge. The elongated, bell-shaped, wide-opening flowers appear near the shoot tip and open at night. The flower cup and the flower tube are covered with wool, hair-like thorns and a few pointed scales.