WMactridae
WAnatina
WAtlantic surf clam
WCrassula aequilatera
WLongimactra
WLongimactra elongata
WLutraria
WLutraria lutraria
WLutraria oblonga
WMactra
WMactra chinensis
WMactra glabrata
WMactra glauca
WMactra ovata
WMactra stultorum
WMulinia
WMulinia cleryana
WMulinia lateralis
WRangia (bivalve)
WRangia cuneata
WScissodesma
WSpisula
WSpisula sachalinensis
WSpisula solida
WSpisula subtruncata
WTresus
WTresus capax
WTresus nuttallii
WZenatia
WZenatia acinaces