⚠ Version 1 of The Plant List has been superseded.
This name record (from Tropicos) is not included in version 1.1 of The Plant List. It is possible the same name is included from a different data source, to check this you can search for Pediocactus simpsonii in version 1.1 of The Plant List.
This name is a synonym of Pediocactus simpsonii var. minor .
The record derives from Tropicos which reports it as a synonym (record 50184594
) with original publication details: Colorado Cacti 58: 1940.