Etymology - From the Greek "pteron" meaning wing - which makes reference to the winged seeds of the genus.Pterocactus has become increasingly popular in cultivation, perhaps due to its unique characteristics and small size. The genus is part of the subfamily Opuntioideae and therefore plants do have glochids. They are otherwise, not particularly spiny, though a couples members of the genus have them in greater number.
Most unique among the cactus family is that the flowers of Pterocactus are embedded in the stems to such an extent that it appears the entire stem is merely a long floral tube. The flowers come right out the end of a stem, which terminates the stem growth as a result and a new stem will then branch off the side and grow until it, in turn, results in a flower. If the flower is successful, the end of the stem will develop into a dry fruit that later splits open and reveals seeds with wide wings that are also unique within the cactus family. In fact, the seeds look very much like those of an Elm (Ulmus) tree. Furthermore, Pterocactus species feature large tuberous roots, which continue to grow, while the stems may fade away and be replaced by new ones over time.
This genus is endemic to Argentina where it grows throughout the region of Patagonia.