This name is a synonym of Rhododendron lapponicum (L.) Wahlenb..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50156437) with original publication details: Bull. Soc. Imp. Naturalistes Moscou 11: 96 1838.
This name was in version 1 of The Plant List, record tro-50156437.