This name is a synonym of Apium inundatum (L.) Rchb.f..
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Sp. Umbell. 115 1818.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:844945-1.
This name was in version 1 of The Plant List, record kew-2365176.