⚠ Version 1 of The Plant List has been superseded.
This name is in version 1.1 of The Plant List, record tro-29201252, with some changes.
This name is a synonym of Penstemon pallidus subsp. arkansanus (Pennell) R.W. Benn..
The record derives from Tropicos which reports it as a synonym (record 29201252) with original publication details: Proc. Acad. Nat. Sci. Philadelphia 73(3B): 493-494 493 1921.
Full publication details for this name can be found in IPNI: urn:lsid:ipni.org:names:187163-2.