This name is a synonym of Penstemon clevelandii subsp. connatus (Munz & I.M. Johnst.) D.D. Keck.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 29207728) with original publication details: Bull. Torrey Bot. Club 49(12): 357 1922.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187271-2.
This name was in version 1 of The Plant List, record tro-29207728, and has not been changed.