This name is a synonym of Oenothera cespitosa subsp. australis (Wooton & Standl.) Munz.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50129273) with original publication details: Fl. Ariz. New Mex. 277 1941.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:172748-2.
This name was in version 1 of The Plant List, record tro-50129273.