This name is a synonym of Penstemon gracilis Nutt..
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50107886) with original publication details: Bull. Acad. Imp. Sci. Saint-Petersbourg 5: 345 1839.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187358-2.
This name was in version 1 of The Plant List, record tro-50107886.