This name is a synonym of Callitriche truncata subsp. fimbriata Schotsman.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 31583) with original publication details: Novosti Sist. Vyssh. Rast. 12: 237 1975.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:139172-1.
This name was in version 1 of The Plant List, record kew-31583, and has not been changed.