This name is a synonym of Rhododendron davidsonianum Rehder & E.H. Wilson.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 12303836) with original publication details: Bot. Mag. 142: , pl. 8665 1916.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:332155-1.
This name was in version 1 of The Plant List, record tro-12303836, and has not been changed.