This name is a synonym of Antennaria rosea subsp. confinis (Greene) R.J.Bayer.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 06B3A8DF-BD78-4433-8E2C-390F7CA6E585).
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 Leontopodium leontopodioides in version 1 of The Plant List.