This name is a synonym of Ranunculus occidentalis var. nelsonii (DC.) L.D. Benson.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 27101499) with original publication details: Fl. Alaska Yukon 4: 762 1944.
This name was in version 1 of The Plant List, record tro-27101499, and has not been changed.