This name is a synonym of Symphyotrichum patulum (Lam.) Karlsson.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record F5AFC617-CD3B-4933-AB26-9AD9D3495C9D) with original publication details: Encycl. (Lamarck) 1(1) 308 1783.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:272858-2.
This name was in version 1 of The Plant List, record gcc-100545, and has not been changed.