Rebutia senilis

It is an olive-green cactaceae with a solitary or grouped stem, with a concavity in its apex. Its rounded areoles hold erect, bristly spines of a white color, from where the term ‘senilis’ ("old") drives. The number of spines and their size are influenced by the cultivation and the light conditions (with poor light it will produce fewer and thinner spines, while with strong light it will produce stronger numerous spines). Flowering occurs during spring, with trumpet-shaped, red, orange or crimson flowers.