Ostreoida

The order Ostreoida includes the oysters and other families of bivalves such as Pectinidae (mostly scallops). 
2010 taxonomy.
In 2010, a new proposed classification system for the Bivalvia was published by Bieler, Carter &amp; Coan, revising the classification of the Bivalvia, including the order Ostreoida.
Order Ostreoida