Number 10... Elasmosaurus!
Elasmosaurus is a marine reptile with a length of 12 meters. It might have used its long neck to sift the sand at the bottom of the sea to check for small sea animals to eat (this is my opinion - it also ate fish). It was so big that one vertebrae waeighed 4.2kg!
Number 9... Icthyosaurus!
Ichthyosaurus was the most fish-like reptile I know about. When it was still a pup it probably hid in coral reefs to hide from sharks, only coming out to breathe air. Fun fact- Icthyosaurus gave live birth! They were probably preyed on by the next reptile on this list...
Number 8... Liopleurodon!
Liopleurodon was thought to have a maximum length of a staggering 100 feet long! However, it was actually 6 meters long (19 feet) so it doesn't land very high on this list, but it did have an interestingly strong sense of smell.
Number 7... Quetzalcoatlus!
This pterosaur is on this length because of its size. It stood 6 meters tall (as tall as a giraffe) and had a wingspan of 12 meters, the same as a small plane! It even ate sauropods (they were only the size of ponies, but come on, it's still awesome!)
Number 6... Babibasilicus!
Unlike the other entries on this list, babibasilicus wasn't a marine reptile nor a pterosaur, but it had to be included. It was the prehistoric Basilisk lizard- a lizard that could walk on water!
Number 5... Tanystropheus!
Tanystropheus is a marine reptile which literally walked at the bottom of the body of water it resided in!
Number 4... Cyodrakon!
This pterosaur is nearly the size of quetzalcoatlus, but its name is much cooler- the translation is 'cold dragon of the North winds'. It is also Canada's first pterosaur.
Number 3... Nothosaurus
This marine reptile is rather small, but had strong jaws with teeth like a trap which were practically impossible to escape.
Number 2... Nemicolopterus!
This pterosaur wasn't huge like Cyodrakon and Quetzalcoatlus, so why is it even on the list let alone number 2?! Well, it is on the list for the opposite reason- its wingspan was only 10 inches!
Number 1... Mosasaurus!
Mosasaurus is one of the largest ever sea creatures- with a length of 17 meters, it was the apex predator. It also had a serpentine body, as it was related to snakes.