This name is a synonym of Rhododendron moulmainense Hook..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50060665) with original publication details: J. Fed. Malay States Mus. 4: 43 1909.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:332760-1.
This name was in version 1 of The Plant List, record tro-50060665, and has not been changed.