This name is a synonym of Rhododendron discolor Franch..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50000679) with original publication details: Bull. Misc. Inform. Kew 1910(4): 110 1910.
This name was in version 1 of The Plant List, record tro-50000679, and has not been changed.