Harrisia bonplandii is a species of cactus and can be found in the southwest of Brasil, in Paraguay, in Bolivia and in the north of Argentina in the Chaco .The cactus plants in the Gran Chaco are generally called Tuna and this specific variety Reina de la Noche. Fruits and roots are edible and well known to the native nations of the Gran Chaco.
It is stem scandent, clambering or sprawling and grows up leaning-climbing. The stems have diameters of up to 5 centimeters and are up to 2.5 meters long. They are three to four edged with flat faces. Their edges are sharp and wavy. The single strong central spine is up to 2.5 centimeters long. The four to five side spines reach a length of 4 to 5 millimeters The flowers reach a length of 20 to 25 centimeters Their pericarpel and the corolla tube are virtually without wool, but filled with large scurf’s. The spherical, redfruits are edible and strongly tuberculate. They have diameters of 4 to 4.5 centimetres.