The first description as
Cereus tetracanthus was made in 1855 by J. Labouret. David Richard Hunt placed the species in the genus Harrisia in 1987. Further
nomenclature synonyms are
Eriocereus tetracanthus (Labour.) Riccob. (1909),
Trichocereus tetracanthus (Labour.) Borg (1937),
Roseocereus tephracanthus (Labour.) Backeb. (1942),
Roseocereus tetracanthus (Labour.) Backeb. (1942) and
Echinopsis tetracanthus (Labour.) Anceschi & Magli (2013). == References ==