Bivalvia, in previous centuries referred tae as the Lamellibranchiata an Pelecypoda, is a cless o marine an freshwatter molluscs that hae laterally compressed bouks enclosed bi a shell conseestin o twa hinged pairts. Bivalves as a group hae na heid an they lack some uisual molluscan organs lik the radula an the odontophore.
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