Pilosocereus leucocephalus Mexico, Sonora, near Horcasitas, H. Poselger s.n. (not preserved) Mexico, [San Luis] Potosí, [Galeotti?] (not preserved) Holotype: Guatemala, Jalapa, near El Rancho, 4 Apr 1905, W.R. Maxon & R.R. Hay 3769 (US: 00115542) Holotype, neotype: Mexico, Tamaulipas, near Victoria, alt. 320 m, 1 May–13 Jun 1907, Palmer 362 (US: 00115543, isotypes: NY 00120557, CM 1478, K 000062714) Holotype: Mexico, Veracruz, 1908, C.A. Purpus s.n. (US: 00115545)