Cleistocactus Lem. in Ill. Hort. 8: Misc. 35. 1861 sec. Hunt 2016
  • =Maritimocereus Akers & Buining in Succulenta (Netherlands) 1950: 49. 1950 syn. sec. Hunt 2006
  • =Winterocereus Backeb., Kakteenl.: 455. 1966 syn. sec. Hunt 2006



The broad circumscription of Cleistocactus as employed by Anderson (2001, 2005), and Hunt (2006) goes back to the Cactaceae consensus classification reported by Hunt & Taylor (1986), where the predominantly ornithophilous floral syndrome was used as diagnostic character. Schlumpberger & Renner (2012) found that Cleistocactus s.l. is polyphyletic - the monotypic Cephalocleistocactus was placed as sister to Yungasocereus, while Cleistocactus s.str. is sister to Vatricania next to Weberbauerocereus, and two terminals representing the former Borzicactus and Loxanthocereus are placed in the Oreocereus clade, the former next to Matucana, and the latter next to Haageocereus.
Deciding whether Cleistocactus s.l. should be retained or split up is difficult, since sampling of the group and its possible sister taxa is still inadequate. The affiliation of Loxanthocereus with Haageocereus was seen earlier and Nyffeler & Eggli (2010) listed it as synonym of Haageocereus.A
A. Hernández-Ledesma, P., Berendsohn, W.G., Borsch, T., von Mering, S., Akhani, H., Arias, S., Castañeda-Noa, I., Eggli, U., Eriksson, R., Flores-Olvera, H., Fuentes-Bazán, S., Kadereit, G., Klak, C., Korotkova, N. & Nyffeler, R. 2015: A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales. – Willdenowia 45(3): 281-383