This name is a synonym of Frangula rubra subsp. obtusissima (Greene) Kartesz & Gandhi.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Fl. Calif. 2: 459 1936.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:219064-2.
This name was in version 1 of The Plant List, record kew-2528965, and has not been changed.