This name is a synonym of Penstemon grinnellii var. scrophularioides (M.E. Jones) N.H. Holmgren.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50084323) with original publication details: Contr. W. Bot. 12: 65–66 1908.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:307313-2.
This name was in version 1 of The Plant List, record tro-50084323.