This name is a synonym of Spirodela oligorrhiza (Kurz) Hegelm..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 109318) with original publication details: J. Linn. Soc., Bot. 9: 267 1866.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:526204-1.
This name was in version 1 of The Plant List, record kew-109318.