It is an extremely small cactus, very small in size (about 1-2 cm in diameter) - a characteristic, from which the name of the species derives. It is a solitary cactacea that over time can cluster, it has no ribs or spines, it is of a globular shape, slightly depressed at the apex, and of a dark green color. In summer, it blooms with tender white or pink flowers of about 10-15 mm in diameter, which sometimes cover the whole plant.