This name is a synonym of Penstemon eriantherus var. whitedii (Piper) A. Nelson.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 29203930) with original publication details: Bot. Gaz. 22(6): 490–491 1896.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:187859-2.
This name was in version 1 of The Plant List, record tro-29203930.