This name is a synonym of Symphyotrichum anticostense (Fernald) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record E16D3EE3-65E1-48BA-BA7A-646F4E49C1A2) with original publication details: Rhodora 17 16 1915.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23072-2.
This name was in version 1 of The Plant List, record gcc-76323.