This Specimen has been sold.
2.5" Bumpy Douvilleiceras Ammonite
Here is a nice ammonite of a species not typically seen from Madagascar, Douvilleiceras mammilatum. It still has much of it's shell and a mother-of-pearl type iridescence to it. It is Upper Cretaceous in age and is covered in spiny knobs. These spiny knobs would have acted as defensive structures while it was alive.