⚠ Version 1 of The Plant List has been superseded.
This name is in version 1.1 of The Plant List, record tro-50079836, with some changes.
This name is a synonym of Penstemon confertus var. attenuatus (Douglas ex Lindl.) M.E. Jones.
The record derives from Tropicos which reports it as a synonym (record 50079836) with original publication details: Bull. Sci. Acad. Imp. Sci. Saint-Pétersbourg 5: 345 345 1839.
Full publication details for this name can be found in IPNI: urn:lsid:ipni.org:names:187355-2.