This name is a synonym of Korthalsella japonica f. grayi (Barlow) Molvray.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50113449) with original publication details: Brunonia 6: 46 1983.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:902305-1.
This name was in version 1 of The Plant List, record tro-50113449, and has not been changed.