Maihuenia, Gesamtbeschr. Kakt.: 754. 1897–1899 sec. Hunt 2006
- ≡Pereskia subg. Maihuenia in Bois, Dict. Hort.: 938. 1898 syn. sec. Hunt 2006
- Type: Maihuenia poeppigii
Category B. The genus is monophyletic based on phylogenetic studies that support the clade based on a sufficiently dense or even complete sampling, or support a monotypic genus as a distinct lineage, but do not provide a new taxonomic treatment at the species level. In many cases, older classical taxonomic synopses or a monographic treatment exist for these genera providing a reliable assessment of the species included.