This name is a synonym of Carduus nutans L..
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 021D9DC8-9CAE-4C0F-91C1-415B0FD6166E) with original publication details: Naturaliste Canad. 94 654 1967.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:45568-2.
This name was in version 1 of The Plant List, record gcc-35255.