Table 1

The distribution of the 41 freshwater gastropod species confirmed from Mid-Atlantic drainages, tabulated by state.  Note that the grand total exceeds 2,905 because of double-counting at state lines.

Confirmed in this study
WV
MD
DC DE NJ PA
Amnicola limosa 2 17   12 46 27
Aplexa elongata           1
Cipangopaludina chinensis         20 14
Cipangopaludina japonica   4 1   4 14
Bithynia tentaculata   4 1 1    
Campeloma decisum 3 19   11 24 36
Ferrissia fragilis 3 45   32 37 36
Ferrissia rivularis 10 73   13 12 118
Fontigens bottimeri   15 2      
Fontigens nickliniana           5
Fontigens orolibas   1       1
Gyraulus deflectus       3 5  
Gyraulus parvus 2 17   18 52 36
Helisoma anceps 2 18   6 29 46
Helisoma campanulata         7 7
Helisoma trivolvis 3 9   8 49 48
Laevapex fuscus 2 3   2 21 11
Leptoxis carinata 7 48       77
Lioplax subcarinata         1  
Littoridinops tenuipes   11   2 5 1
Lymnaea catascopium   1     10 6
Lymnaea columella 2 39   33 47 36
Lymnaea elodes   1     3 4
Lymnaea humilis 5 74   21 45 54
Lyogyrus granum 1 11   19 11 16
Menetus dilatatus 5 101   63 51 44
Physa acuta 8 241 2 85 158 208
Physa carolinae   4   1    
Physa gyrina 4 9     16 55
Physa pomilia   11        
Physa vernalis           1
Planorbula armigera   7   2 10 3
Pleurocera proxima           1
Pleurocera virginica 3 32 1 3 21 62
Pomatiopsis lapidaria       3 1  
Potamopyrgus antipodarum      1
Promenetus exacuous   1   1 7 2
Somatogyrus pennsylvanicus         3 7
Valvata bicarinata         2  
Valvata tricarinata   1     14  
Viviparus georgianus   1     7
TOTALS 62 818 8 339 718 978

    

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