In 1964 Martín Cárdenas, noted Bolivian cactologist, described P. taratensis from between Tarata and the Río Caine. That same year German explorer Wolfgang Krahn found another population nearby. Walter Weskamp later described material from this population as P. krahnii, a name now considered a synonym of P. taratensis. The species has golden-yellow flowers and the spination includes chestnut-brown, usually prominently hooked centrals. The stems tend to become clavate and have spirally arranged ribs. We offer HBG 97499, plants grown from controlled pollination of W. Krahn 167 originally collected at 2200 m elevation between La Viña and the Río Caine, Prov. Tarata, Dept. Cochabamba, Bolivia. $5.
Published in the Cactus and Succulent Journal, Vol. 80 (2), March - April, 2008