This name is a synonym of Oenothera parviflora subsp. angustissima (R.R. Gates) Munz.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50089681) with original publication details: Rhodora 15(171): 46–48, pl. 100–101 1913.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:172731-2.
This name was in version 1 of The Plant List, record tro-50089681.