From editor or global species database
Nomenclature Wenz (1919) introduced Theodoxis helvetica as new name for Theodoxia [sic] ferussaci Locard, 1893, non Neritina ferussaci Recluz, 1850, apparently by Wenz considered to be congeneric. Although no homonymy exists at present, the secondary homonym was replaced before 1961 and is thus permanently invalid (ICZN Art. 59.3). [details]