This name is a synonym of Begonia grandis subsp. sinensis (A.DC.) Irmsch..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 361168) with original publication details: Repert. Spec. Nov. Regni Veg. 7: 21 1909.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:104340-1.
This name was in version 1 of The Plant List, record kew-361168, and has not been changed.