⚠ Version 1 of The Plant List has been superseded.
This name is in version 1.1 of The Plant List, record tro-29201259, with some changes.
This name is a synonym of Penstemon heterophyllus var. azureus (Benth.) Jeps..
The record derives from Tropicos which reports it as a synonym (record 29201259) with original publication details: Pl. Hartw. 327 327 1849.
Full publication details for this name can be found in IPNI: urn:lsid:ipni.org:names:808007-1.