Top 20 Most Incredible Prehistoric Sea Monsters

Time travelers should stay out of the water! For this list, we’ll looking at the most fascinating and remarkable sea creatures from prehistoric times. Our countdown includes Mesosaurus, Kronosaurus, Helicoprion, Megalodon, Livyatan Melvillei, and more! What's YOUR favorite prehistoric sea monster? Let us know in the comments!

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#SeaMonsters #Prehistoric #Scary

[WatchMojo]

Would you want them to bring back any of these sea creatures... or glad they are left in the past?

[mr.decencykeepinitreal]

Megalodon is such a terrifying but also impressive prehistoric sea creature.

[cookscreativecorner]

So glad to see a couple of obscure ones on here. My favorites are the Megalodon, Liopleurodon, Livyatan, Dunkleosteus, and Kronosaurus. Now this reminds me I really need to reread the Meg series soon.

[Lloveu]

We only know 5% of the ocean tell me again that these things aren’t still out there.

[akatsukijutsu]

Turned my phone on saw watchmojo and sea creatures and was like yep I'm watching it lol

[MegaJSK]

Is it just me, or is Cretoxyrhina one of the most badass names you've ever heard!

[charfree]

People are looking for the Kraken but the Kraken is away looking for the manager.

[Bdawg]

Elasmosaurus showed up. He wants his tree fiddy.

[shatteredthunder]

It’s a magical Liopleurodon, Charlie! It’s gonna guide our way to Candy Mountain!

[jondeiconic]

Yup prehistoric sea area are dangerous before with many types of sea creatures

[lannce]

“Many fearsome fish have swam the worlds oceans”
WOW YOU DONT SAY

[dragonslayergod]

People saying ooh megalodon come back like the size it was I would love to see megalodon come back and try to survive in today's climate

[langux]

Fun fact : In Switzerland it is illegal to own just one guinea pig.

[bobusan_duuuugnut-oh]

The liopleurodon is magical creature. Just ask Charlie.

[Isiah]

Please do more prehistoric creatures, and more dinosaurs too!‼️🦕

[shainewhite]

I love giant prehistoric sea reptiles! Been fascinated by them since Disney's Fantastia the Rite Of Spring Sequence. And Walking With Dinosaurs as well as Chased By Sea Monsters.

[AifDaimon]

That Moana reference during the Mauisaurus entry just couldn't be helped, could it!? HAHAHAHHAHAHAHAHAHA

[wixdraco]

“It’s a Liopleurodon, Charlie! A Liopleurodon!”

[Jojuiced]

It’s a good thing these are all extinct otherwise going underwater in the worlds ocean’s would be a no go.

[slifer_yt]

I like the well deserved exposure you guys are giving these extinct animals, and the history lesson as well. I hope to see more of these kinds of videos