Gryphaea arcuata (Lamarck)

Gryphaea arcuata (Lamark)
Locally known as devils toe nails 
This bivalve has been prepared in my workshop to a very high standard even down between the two valves.
This one was collected from the banks of the river Severn in Fretherne (Hock cliff ) in Gloucester which is the type location.
It comes from the lower lias,Jurassic,Bucklandi zone and measures 57mm x 33mm