Shark Protolamna sokolovi

A late Cretaceous Period (about 112 million years ago) fossil tooth of the Protolamna sokolovi shark. This fossil is from the rare Lamnid shark. It was found in the Paw Paw Formation found in Tarrant County, Texas.

Crowns feature deep longitudinal grooves at the base.

Thanks to Herb for the image.

Mortoniceras Ammonite Fossil

The distinctive ribbed coiled ammonite is known as the Mortoniceras sp. found in Tarrant County, Texas. It was found in Duck Creek Formation and the creature existed in Upper Cretaceous Period (Albian Stage; approximately 100 million years ago).

Thanks to Herb for allowing me to photograph this specimen.

Bryozoan Holdfasts

This entry shows a number of Ordovician Period bryozoan holdfasts. They were found in Franklin County, Kentucky in the Lexington Limestone.

Thanks to Kenny for the images.