I just noticed the WoRMS database includes at least one non-marine species, or at least that is how I would describe the below species...so where is the line being drawn on that (eg other freshwater snails from normally marine families like Neritidae?) 

WoRMS taxon details

Checked: verified by a taxonomic editorCipangopaludina chinensis (Gray, 1834) 
AphiaID: 594807 


Classification: Biota > Checked: verified by a taxonomic editorAnimalia (Kingdom) > Checked: verified by a taxonomic editorMollusca (Phylum) > Checked: verified by a taxonomic editorGastropoda (Class) > Checked: verified by a taxonomic editorCaenogastropoda (Subclass) > Checked: verified by a taxonomic editorArchitaenioglossa (Order) > Checked: verified by a taxonomic editorViviparoidea (Superfamily) > Checked: verified by a taxonomic editorViviparidae (Family) > Checked: verified by a taxonomic editorBellamyinae (Subfamily) > Checked: verified by a taxonomic editorCipangopaludina (Genus) > Checked: verified by a taxonomic editorCipangopaludina chinensis (Species)  

Status   accepted 
Rank   Species 
Parent   Checked: verified by a taxonomic editorCipangopaludina Hannibal, 1912 
Orig. name   Checked: verified by a taxonomic editorPaludina chinensis Gray, 1834 
Synonymised
names   Checked: verified by a taxonomic editorPaludina chinensis Gray, 1834 (original combination)
 Checked: verified by a taxonomic editorVivipara chinensis (Gray, 1834)
  
Source   basis of record Lu H.-F., Du L.-N., Li Z.-Q., Chen X.-Y. & Yang J.-X. (2014). Morphological analysis of the Chinese Cipangopaludina species (Gastropoda; Caenogastropoda; Viviparidae). Zoological Research. 35(6): 510-527., available online at http://dx.doi.org/10.13918/j.issn.2095-8137.2014.6.510 [details]


 
Vernacular
Names   
Language    Name   
English  Unreviewed: has not been verified by a taxonomic editorChinese mysterysnail  [details] 
 

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