1. Squid

A prehistoric squid. Remains of these animals have been found near Australia, Germany, and in the Western Interior Seaway, a vast sea that once bisected North America.

2. Bacculite

Also called a straight ammonite, Bacculite is an ammonite mollusk with a straight, not spiraled, shell.

3. Caproberyx

Fossils of Caproberyx indicate they swam the waters of Europe and Africa during the Cretaceous period.

4. Enchodus

A row of swordlike fangs gives the Enchodus its nickname: saber-toothed herring.

5. Gillicus

The microscopic teeth of the Gillicus suggest it was a filter feeder that ate zooplankton, similar to today’s baleen whales.

6. Kronosaurus

Four paddle-like flippers helped the Kronosaurus move underwater much like sea turtles.

7. Nothosaur

With its leathery skin, long tail, short legs, and needle-like teeth, the Nothosaur resembled a prehistoric crocodile.

8. Protostega

At more than ten feet (three meters) long, Protostega were among the largest turtles to ever live. Despite their size, they were excellent swimmers.

9. Squalicorax

Also called crow sharks for their habit of scavenging, Squalicorax had teeth resembling those of today’s tiger sharks, suggesting that their diet was similar too.

10. Styxosaurus

Styxosaurus was a long-necked marine reptile that grew upwards of 40 feet (12 meters) long. About half of that length was neck.

11. Temnodontosaurus

With eyes 10 inches (25.4 centimeters) wide, Temnodontosaurus could see in near lightless conditions and probably dove for food.

12. Bananogmius

Bananogmius was equipped with flat jaws and palatine plates that helped it crush its favorite prey, clams and mollusks.

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