FOSSIL
SCALLOP SHELLS
Scallops are common marine bivalves in much of the
fossil record and in the modern oceans. Individual bivalve shells, unlike
brachiopod shells, are asymmetrical. Scallop shells sometimes approach bilateral
symmetry, but the subtriangular, wing-like auricles along the hingeline will
still display asymmetry. One of the auricles has a basal notch. A
notched auricle on the right side of a shell indicates a right valve. A
notched auricle on the left side of a shell indicates a left valve.
Carolinapecten
eboreus (Conrad, 1833) (above
& below) (4.9 cm across at its widest) - this fossil scallop shell is from
the Yorktown Formation (Lower to Middle Pliocene) at the Lee Creek Phosphate
Mine (southern shore of Pamlico Sound, near Aurora, southern Beaufort County,
eastern North Carolina).
This is a right valve (anterior is to the right).
Classification:
Mollusca, Bivalvia, Pteriomorphia, Pterioida, Pteriina, Pectinoidea, Pectinidae
Placopecten
clintonius (Say, 1824) (5.0 cm
across at its widest) - here’s another scallop shell from the Yorktown
Formation (Lower to Middle Pliocene) at the Lee Creek Phosphate Mine (southern
shore of Pamlico Sound, near Aurora, southern Beaufort County, eastern North
Carolina). This is a left valve
(anterior is to the left).
Classification: Mollusca, Bivalvia, Pteriomorphia, Pterioida,
Pteriina, Pectinoidea, Pectinidae)