Cuzco, Trichocereus cuzcoensis (10-12" Tip cutting)
Trichocereus cuzcoensis. - There are vendors out there (that will remain nameless), that used to sell this exact cultivar as T. peruvianus. The entire community begs to differ. :) There are many traits that make this plant clearly a cuzco: the notching, central main outward spine, etc. Cuzco's are known for that intense central spine, I know I used to get stabbed by it all the time before I got my HexArmor ThornArmor Cactus Gloves
A beautiful cactus and I know from personal experience that it makes an excellent grafting stock.