What is gryphaea?

Gryphaea, commonly known as the devil's toenail, is an extinct genus of bivalve mollusks that lived during the Jurassic and Cretaceous periods. These creatures had distinctive, coiled shells that resemble a toenail, hence their nickname.

Gryphaea fossils can be found all over the world, particularly in Europe and North America. They were filter feeders, using their long, curved shells to filter food particles from the water.

These animals lived in shallow marine environments and are often found in association with other marine fossils, such as ammonites and belemnites. Gryphaea were an important part of the marine ecosystem during the Jurassic and Cretaceous periods.

Today, Gryphaea fossils are popular among collectors and are often used by researchers to study the ancient marine environments in which they lived. The name Gryphaea comes from the Greek word "gryphos," which means claw, in reference to their distinctive shape.