Reicheocactus in Cactaceae (Berlin) 1941(2): 76. 1942 sec. Hunt 2016
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.
Excluded from Echinopsis by Schlumpberger & Renner (2012); cf. Hunt (2016), CITES Cactaceae Checklist 3rd edition; see also note under Echinopsis.A