This name is a synonym of Symphyotrichum novi-belgii var. crenifolium (Fernald) Labrecque & Brouillet.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 63533099-67F3-4167-BBD5-28F2E640404A) with original publication details: Bull. Torrey Bot. Club 74 143 1947.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23276-2.
This name was in version 1 of The Plant List, record gcc-22136.