Espostoa

E. nana (= E. melanostele subsp. nana) is a columnar cactus densely covered with white hair distinguished from the standard E. melanostele for its smaller stems and the wool on the cephallum is white to pale yellow (mostly yellow-brown in E. melanostele).

Tall columnar cactuscovered with dense white hairs to 10 mm long clothing the whole stem. The spines are very short, numerous at first yellow conceiled, among the wool.