Monday, August 12, 2013

Ostrea falcata pelecypod from New Jersey

Up for viewing today are a couple of Ostrea falcata fossil oysters from the Cretaceous of New Jersey. These are uncommon fossils that I found in the Navesink formation exposed along Big Brook in Monmouth County, NJ. There is a layer where these are found in more abundance that could represent a storm deposit or possibly a calm period which allowed colonization of the seafloor. This species is very similar looking to the more common Ostrea mesenterica (that I'll post about later) but O. falcata has obvious surface ornamentation.

Left valve
Anterior
Left profile
Posterior
Right profile
Right valve

Here is a second specimen: Left valve
Anterior
Left profile
Posterior
Right profile
Right valve... Note the bore hole made by a predatory snail.

I also have a steinkern of a much larger specimen of O. falcata that came from the C&D canal in Delaware. I purchased it at a show put on by the Delaware Mineralogical Society.

Left valve
Right valve
Anterior
Left profile
Posterior


All the above specimens come from the Masstrichtian stage of the Cretaceous when New Jersey and Delaware were submerged under the Atlantic Ocean and Philadelphia was beachfront property.

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