Invertebrate Fossils of NJ
Exogyra sp. (Say)
The oysters Exogyra and
Pycnodonte were the most common bivalves of the Cretaceous period.
Lying on the seabed floor with the convex side in the mud and the flat
side position at the seafloor surface for camouflage. Exogyra
first appeared in the lower Cretaceous and had disappeared by the upper
Cretaceous. These fossil remains can be found in abundance at numerous
locations in Monmouth County.
Exogyra cancellata (Stephenson)
Exogyra costata from Monmouth County, NJ
Characteristic spiral coil of Exogyra.
Exogyra sp. with both valves.
The example of Exogyra spinifera measures over 5 inches across.
Upper valve from an unknown species.