This name is a synonym of Penstemon pseudoputus (Crosswh.) N.H. Holmgren.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 29204316) with original publication details: Amer. Midl. Naturalist 77(1): 35–37, f. 1 [map] 1967.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187849-2.
This name was in version 1 of The Plant List, record tro-29204316, and has not been changed.