ID Keys
*Images in development

Mactroidea

#1
Elongate, subelliptical shells with a deep pallial sinus
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Wedge-shaped to trigonal-subovate shells with a short pallial sinus
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#2
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Posterior dorsal margin concave
Lutraria magna
  
Posterior dorsal margin not concave, sloping
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#3
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Pallial sinus never confluent with pallial line
Lutraria lutraria
  
Pallial sinus largely confluent with pallial line
Lutraria angustior
  
#4
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Donaciform (wedge-shaped), anterior cardinal teeth not forming an inverted V
Donacilla cornea
  
Subovate trigonal, anterior cardinals in LV forming an inverted V-shape
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#5
Shells thin, brittle, lateral teeth smooth, pallial sinus broad
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Shells robust, lateral teeth serrated, pallial sinus narrow
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#6
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Anterior cardinal tooth in RV parallel to dorsal margin
Mactra stultorum
  
Anterior cardinal tooth in RV angled away from dorsal margin (southern)
Mactra glauca
  
#7
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In low salinity waterways
Rangia cuneata
  
In fully saline environments
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#8
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Shell trigonal, some attenuated posteriorly, apical angle around 120°, pallial sinus extending to the rear of the posterior lateral tooth i9n LV
Spisula subtruncata
  
Shell subovate-subtrigonal, apical angle around 140°, pallial sinus extending beyond the midline of the posterior lateral in the LV
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#9
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Rather thin, brittle shells, inverted v-shaped teeth extending across the whole of the hinge plate
Spisula elliptica
  
Solid shells, inverted v-shaped teeth extending across half of the hinge plate
Spisula solida