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 754352AC-5B97-4CFA-8762-8597974DA1E0) with original publication details: 412 1856.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:260881-1.
This name was in version 1 of The Plant List, record gcc-91114.