This name is a synonym of Xanthium orientale subsp. riparium (Čelak.) Greuter.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record 33C8AE9E-B5CE-4941-BD57-5A8C72DA8EF9) with original publication details: 83 1976.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:260882-1.
This name was in version 1 of The Plant List, record gcc-48894.