This name is a synonym of Rhododendron argyrophyllum subsp. nankingense (Cowan) D.F. Chamb..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50060247) with original publication details: Bot. Mag. 144: , pl. 8767 1918.
This name was in version 1 of The Plant List, record tro-50060247, and has not been changed.