You selected Spirodela polyrrhiza var. masonii Daubs. This is a synonym for:

Accepted scientific name:
Spirodela polyrrhiza (L.) Schleid. (accepted name) 1 literature reference for Spirodela polyrrhiza (L.) Schleid.
Synonyms:
Lemna bannatica Waldst. & Kit. ex Schleid. (synonym) 1 literature reference for Lemna bannatica Waldst. & Kit. ex Schleid.
Lemna major Griff. (synonym) 1 literature reference for Lemna major Griff.
Lemna maxima Blatt. & Hallb. (synonym) 1 literature reference for Lemna maxima Blatt. & Hallb.
Lemna orbicularis Kit. ex Schult. (synonym) 1 literature reference for Lemna orbicularis Kit. ex Schult.
Lemna orbiculata Roxb. (synonym) 1 literature reference for Lemna orbiculata Roxb.
Lemna polyrrhiza L. (synonym) 1 literature reference for Lemna polyrrhiza L.
Lemna polyrrhiza var. concolor Kurz (synonym) 1 literature reference for Lemna polyrrhiza var. concolor Kurz
Lemna thermalis P.Beauv. ex Nutt. (synonym) 1 literature reference for Lemna thermalis P.Beauv. ex Nutt.
Lemna transsilvanica Schur (synonym) 1 literature reference for Lemna transsilvanica Schur
Lemna umbonata A.Br. ex Hegelm. (synonym) 1 literature reference for Lemna umbonata A.Br. ex Hegelm.
Lenticula polyrrhiza (L.) Lam. (synonym) 1 literature reference for Lenticula polyrrhiza (L.) Lam.
Spirodela atropurpurea Montandon (synonym) 1 literature reference for Spirodela atropurpurea Montandon
Spirodela maxima (Blatt. & Hallb.) McCann (synonym) 1 literature reference for Spirodela maxima (Blatt. & Hallb.) McCann
Spirodela polyrrhiza var. masonii Daubs (synonym) 1 literature reference for Spirodela polyrrhiza var. masonii Daubs
Telmatophace orbicularis (Kit. ex Schult.) Schur (synonym) 1 literature reference for Telmatophace orbicularis (Kit. ex Schult.) Schur
Telmatophace polyrrhiza (L.) Godr. (synonym) 1 literature reference for Telmatophace polyrrhiza (L.) Godr.
Common names: -
Classification:
Plantae
Phylum Magnoliophyta
Class Liliopsida
Order Alismatales
Family Araceae
Genus Spirodela
Distribution: Cosmopolitan
Additional data: -
Source database: World Checklist of Selected Plant Families, 27 Nov 2009
Latest taxonomic scrutiny: Govaerts R., 11-Nov-2003
Online resource: http://apps.kew.org/wcsp/namedetail.do?accepted_id=194600&repSynonym_id=-9998&name_id=194600&status=true
CoL taxon LSID: urn:lsid:catalogueoflife.org:taxon:25dc41f0-60a7-102d-be47-00304854f810:ac2010