This name is a synonym of Symphyotrichum lanceolatum var. hesperium (A.Gray) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record A5599177-AEDB-49D2-907E-0A6C108F7A4D) with original publication details: Pittonia 4 219 1900.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23594-2.
This name was in version 1 of The Plant List, record gcc-5587.