Marine Reptiles

Today's post is on marine reptiles.  Remember to click on the above Free Printable Download button above to be able to print drawings for coloring.  The most recent drawings, like these marine reptiles... are at the bottom of the list.  

By the way, as I was drawing this I was watching a movie on BYU TV called Magic In The Water.  It is a very sweet movie.  I also recommend the movie Water Horse and the documentaries:  Chased By Sea Monsters, Walking With Monsters, and Walking With Dinosaurs. All of these documentaries are about ancient ocean life...some way before dinosaurs and marine reptiles.  There is also an episode of Walking With Dinosaurs called Cruel Seas, about marine reptiles...especially Liopleurodon.  

This post is all about extinct marine reptiles.  First of all, they were NOT swimming dinosaurs.  They DID live at the same time as dinosaurs, but marine reptiles were in the ocean and perhaps rivers, and the dinosaurs were mainly on land.   Although, some dinosaurs could swim.   Dinosaurs had legs.  Ancient marine reptiles had flippers and often tail flukes.

There were marine reptiles in all three periods of the Mesozoic Era.  Some of the first were tiny and they evolved to become much bigger over the millions of years.   However, not all evolved to be huge.  Some were smaller because that was the niche they filled in the ocean or river etc.  Some lived in very shallow seas and some lived in deep ocean water....and like whales, we can infer that some may have migrated and live both in deep and shallow water.  Some may have swum upstream at the mouth of rivers... where rivers dump into the sea.

Ichthyosaurs looked like a fat dolphin.  Their name means "fish reptile."   The biggest is called Shonisaurus.  Its fossils have been found way inland, away from the modern ocean because places like the Nevada desert were once the bottom of the ocean.   It was up to 70 ft (21 m) long.  It was absolutely huge.  The bigger Shonisaurus was found in British Columbia Canada.  It may have weighed well over 35 tons, or 77,000 lbs.  Shonisaurus was named for the Shoshone Tribe of  Native Americans of the state of Nevada.  A Ichthyosaur State park in the wilderness of south central Nevada they found like 6-7 fossilized skeletons of Shonisaurus and you can go there and see them.  One vertebrae or backbone is the size and shape of a large cylinder...like a large cooking pot.

Shonisaurus, a huge Ichthysaurus

The long neck marine reptiles look somewhat like a Sauropod dinosaur, but the obvious difference is Sauropod dinosaurs had legs the size of tree trunks and lived on land.  While the long neck Plesiosaurs had fins, or flippers, and they lived in the ocean and maybe rivers and lakes.

Now this can get confusing.  There were two types of Plesiosaurs:  There were long neck Plesiosaurs and short neck Plesiosaurs.  The short neck Plesiosaurs most likely fed on the long neck Plesiosaurs, IF they could catch them.

Long neck Plesiosaurs, like Plesiosaurus, swam in a flying motion.  They would paddle their fornt flipperstogether and then their back flippers together, alternately in a flying motion.  They were probably WAY more agile.  The big Plesiosaurs, like Liopleurodon were far less maneuverable.  They had a body shaped roughly like a huge crocodile, more or less.

Plesiosaurus a long neck Plesiosaur surfacing

Plesiosaurs was about  feet long and ate fish, squid, and anything it could get a hold of.  They were very agile and like all long neck Plesiosaurs, they "flew through the water."  Plesiosaurus was a smaller Plesiosaur.  It was 11 ft. long (3.5 m).   There were some Plesiosaurs that were closer to 46 ft (14 m).

Lioplerodon, a short neck Plesiosaur AKA Pliosaur

Liopleurodon was a short neck Plesiosaur.  Short neck Plesiosaurs are called Pliosaurs.  Liopleurodon's  size has been debated for years. Some paleontologists think it was up to 70 feet long.  Others estimate that it was only 30-40 feet long.  The fossils of Liopleurodon are limited with no complete skeleton.  Paleontologists in England have found a partial jawbone of either a Liopleurodon or something like it with a skull that may have been 10 feet (3 m) long and this monster may have been approaching the 70 foot (21 m).  .  .  and weighed up to 150 metric tons or 330,000 pounds. (Note:  I first posted this w/o drawing in the smaller back paddles on Tylosaurus.  It is correct now.) 

Tylosaurus, the largest  Mosasuar

Tylosaurus with Tail Fluke (from previous post)

Tylosaurus was a huge Mosasaur.  They lived in the Cretaceous Period and became the dominant ocean predator.  Around this time the Ichthyosaurs went extinct.  They also may have outcompeted the Plisoisaurs ...or just ate em all.   Tylosaurus may have been up to 55 ft. (17 m) long.  The Tylosaurs were related to snakes and monitor lizards.  Some evidence says that instead of the snake like tail they may have had a tail fluke like a whale.  Besides eating smaller marine reptiles many of the marine reptiles ate Ammonites.  Ammonites were like a modern Nautilus ...think squid with a curly shell.

By the way, there are still living marine reptiles...they are sea turtles and marine crocodiles.

All drawings and content are Copyright Robin Andrew Lyman 2017.