Pectinoidea

The Pectinoidea are a superfamily of marine bivalve molluscs, including the scallops and spiny oysters.

Shell anatomy
All members of this superfamily have a triangular resilium with a nonmineralized medial core that functions below the hinge line.

Families
According to the World Register of Marine Species, the Pectinoidea include these families:
 * Cyclochlamydidae
 * Entoliidae
 * Neitheidae †
 * Pectinidae (scallops)
 * Pleuronectitidae †
 * Propeamussiidae some are known as glass scallops
 * Spondylidae thorny oysters
 * Tosapectinidae †


 * Families brought into synonymy:
 * Propeamussidae: synonym of Propeamussiidae
 * Syncyclonematidae: synonym of Entoliidae