Its name was chosen in honor of Chilean entomologist Carlos E. Porter. They are small spherical cacti, often considered a subgenus of Eriosyce, which tend to take on a cylindrical shape, as they grow. They are easily distinguished from other cactaceae by their very marked ribs, covered by a significant mantle of spines, always rather long and of a light color, although there are species with almost black spines. They have a rather slow growth, but they are also very easy to cultivate, because, as they come from high-altitude areas, they perfectly resist to the most extreme environmental and climatic conditions. They are suitable, therefore, even for novice growers, and will give you brightly colored apical blooms, that will decorate and invigorate your gardens with a refined simplicity!