This name is a synonym of Penstemon pachyphyllus var. congestus (M.E. Jones) N.H. Holmgren.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 29204307) with original publication details: Proc. Calif. Acad. Sci., ser. 2, 5(18): 714–715 1895.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187119-2.
This name was in version 1 of The Plant List, record tro-29204307.