This name is a synonym of Caltha palustris var. alba (Cambess.) Hook.f. & Thomson.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Feddes Repert. Spec. Nov. Regni Veg. 69: 158 1964.
This name was in version 1 of The Plant List, record kew-2693862.