This name is a synonym of Penstemon procerus var. formosus (A. Nelson) Cronquist.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 29204286) with original publication details: Proc. Biol. Soc. Wash. 17(12): 100 1904.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:1074987-2.
This name was in version 1 of The Plant List, record tro-29204286.