This name is a synonym of Platanthera grandiflora (Bigelow) Lindl..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 456617) with original publication details: N. Amer. Native Orchid J. 15: 74 2009.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:60453107-2.
This name was in version 1 of The Plant List, record kew-456617.