This name is a synonym of Symphyotrichum lentum (Greene) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record D5EBB44F-F6E0-48B6-9C6C-1A3B27C355EC) with original publication details: 180 1894.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23665-2.
This name was in version 1 of The Plant List, record gcc-14149, and has not been changed.