Pot: 6,5 cm.
Its name honors Marshall P. Madison. This plant is the best known of all the Matucanas. It is a globular and solitary cactus, that only over time might branch out and stretch up. Its particular epidermis takes on various shades from green to gray and bluish. The number of spines is variable: in some species there are a few of them or there are none at all, in others there are quite many spines on the plant. Its beautiful bright red flowers bloom at the apex. It is an easy to grow plant.