|🌵 Author(s)||Marianna Rodrigues SantosMarlon Machado|
|🌵 Basionym||Discocactus petrhalfarii (2008)|
|🌵 Basionym author(s)||Milan Zachar|
Named for Petr Halfar, son of Miroslav Halfar, one of the discoverers of the species, who died in a car crash in 2005.
Zachar’s original spelling petr-halfari is correctable to petrhalfarii under the articles 60.8 and 60.11 of the International Code of Nomenclature. Sanchos & Machado spelled it petr-halfarii.