Pelecyphora chihuahuensis Holotype: Mexico, Chihuahua, Vicinity of Chihuahua, 8 Apr 1908, E. Palmer 72 (US: 573550) Isotype: Mexico, Chihuahua, Vicinity of Chihuahua, 8 Apr 1908, E. Palmer 72 (K: 250731) Lectotype, lectotype: Fragments from] Potts’s original specimen, cult. 1857, hort., Jan 1857, J. Salm-Dyck s.n. (MO)