This name is a synonym of Geranium erianthum DC..
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Bot. Mag. (Tokyo) 24: 258 1910.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:322484-2.
This name was in version 1 of The Plant List, record kew-2823239, and has not been changed.