This name is a synonym of Oenothera micrantha var. exfoliata (A. Nelson) Munz.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50082484) with original publication details: Bot. Gaz. 85(3): 264 1928.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:173066-2.
This name was in version 1 of The Plant List, record tro-50082484.