This name is a synonym of Penstemon procerus var. tolmiei (Hook.) Cronquist.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50322513) with original publication details: Brittonia 8(4): 249 1957.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187690-2.
This name was in version 1 of The Plant List, record tro-50322513.