This name is a synonym of Oenothera pallida var. trichocalyx (Nutt.) Dorn.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 23202241) with original publication details: Fl. N. Amer. 1(3): 494–495 1840.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:281554-2.
This name was in version 1 of The Plant List, record tro-23202241.