Pot: 14 cm.
The name derives from ancient Latin and literally means "sword-shaped", referring to its thorns. It is a wonderful cactacea with a globular shape, slightly depressed at the top, with well defined, narrow and wavy ribs, sometimes with an irregular pattern. From woolly areoles grow 4 rather short and robust spines, similar in shape to a sharp sword. A woolly white top helps to enrich the appearance of this unusual cactus, and it is from here that, in summer, bright flowers of an almost metallic yellow will bloom.