This name is a synonym of Rhododendron anthosphaerum Diels.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50060182) with original publication details: Sp. Rhodod. 343 1930.
This name was in version 1 of The Plant List, record tro-50060182, and has not been changed.