This name is a synonym of Symphyotrichum falcatum (Lindl. ex Lindl.) G.L.Nesom.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 5DE7F3D2-81FB-4F37-A9E5-51F5B0943A3A).
This name record (from TICA) was not included in version 1 of The Plant List. It is possible the same name was included from a different data source, to check this you can search for Virgulus falcatus in version 1 of The Plant List.