This name is a synonym of Phlox douglasii subsp. rigida (Benth.) Wherry.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50321168) with original publication details: Prodr. 9: 306 1845.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:193650-2.
This name was in version 1 of The Plant List, record tro-50321168.