This name is a synonym of Geranium kauaiense (Rock) H.St.John.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Biotropica 8: 259 1976.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:881096-1.
This name was in version 1 of The Plant List, record kew-2823406, and has not been changed.