Cactaceae are thought to have evolved between 30 and 40 million years ago. The American continent was united to the others, but it was separated progressively by the continental drift. The endemic species of the New World had to develop after this separation; Significant distancing was achieved in the last 50 million years. This could explain the non-existence of endemic cacti in Africa: these evolved in America when the continents had already separated.
The cactus echinopsis oxygona is a species of the cactus family. It is endemic to Chaco, Corrientes, Entre Ríos, Formosa, Jujuy, Salta, Santa Fe and Santiago del Estero in Argentina; Paraguay; Chuquisaca, Santa Cruz and Tarija in Bolivia and Uruguay. It is an abundant species in its natural habitat.
Medium green spherical body cactus with 8 to 14 rounded ribs. The areloas, somewhat sunken, are white, from which arise the slightly darker spines at its end.
Cacti endure drought well, but like all plants they also need water to live. It is advisable to allow the substrate to dry between irrigation and irrigation. It is very important that the soil does not become soaked: too much water and, above all, a poorly drained substrate causes the appearance of fungi and the death of the plant. In fact, one of the biggest mistakes in caring for cacti is over-watering.