This name is a synonym of Rhododendron pulchrum Sweet.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50060752) with original publication details: Hort. Brit. (ed. 2) 343 1830.
This name was in version 1 of The Plant List, record tro-50060752, and has not been changed.