This name is a synonym of Begonia arborescens var. oxyphylla (A.DC.) S.F.Sm..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 362515) with original publication details: Ann. Sci. Nat., Bot. IV, 11: 140 1859.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:318912-2.
This name was in version 1 of The Plant List, record kew-362515, and has not been changed.