This name is a synonym of Symphyotrichum patens var. patentissimum (Lindl. ex DC.) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 90C1EFD1-1835-4D53-9858-8D68E0F45B3E) with original publication details: Bull. Torrey Bot. Club 25 620 1898.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:23250-2.
This name was in version 1 of The Plant List, record gcc-94616, and has not been changed.