Fossil Oysters

Instead of having these fossils lying around in cans and boxes, I decided to glue a collection of them in one of the many arrowhead frames I've made. These are Gryphaea, commonly known as Devil's toenails. They are an extinct oyster. These were all found just south of De Leon, Texas. 

More about these fossils...

Gryphaea, common name Devil's toenails, is a genus of extinct oysters, marine bivalve mollusks in the family Gryphaeidae.

These fossils range from the Jurassic to the Cretaceous periods. They are particularly common in many parts of Britain.

These oysters lived on the sea bed in shallow waters, possibly in large colonies. The complete fossils consist of two articulated valves: a larger gnarly-shaped shell (the "toenail") and a smaller, flattened shell, the "lid". The soft parts of the animal occupied the cavity between the two shells, just like modern oysters. The shells also feature prominent growth bands. The larger, curved shell sat within the mud on the sea floor. These shells are sometimes found in fossil plates along with Turritella, clams, and sometimes sharks' teeth and fossilized fish scales.