This name is a synonym of Oenothera grandiflora var. tracyi (Bartlett) R.R. Gates.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50089481) with original publication details: Rhodora 13(154): 210–211, pl. 93 1911.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:173493-2.
This name was in version 1 of The Plant List, record tro-50089481.