10 Scary Extinct Animals

Written by Volia Schubiger
Published: July 18, 2022
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Extinction is a grave issue that continues to happen on our planet. There have been many animals that once roamed the earth that no longer exists anymore. While in some cases, this is very sad, in other cases, it can be a bit of a relief. After all, some extinct animals were so scary that we wouldn’t want to have to come in contact with them. However, if creepy and terrifying creatures interest you, then we’ve got you covered. 

Below are 10 scary extinct animals that you won’t believe ever inhabited this earth.

10. Titanoboa

Titanoboa illustration

Titanoboa cerrejonensis, the largest snake in the world, belongs to the family of boas.

©Michael Rosskothen/Shutterstock.com

It is probably best to skip this one if you are afraid of snakes. That’s because there has never been a snake larger than Titanoboa. It is believed that Titanoboa lived during the Paleocene era, and it was around 40 feet long. Paleontologists estimate that the Titanoboa measured 12 meters (40 feet) in length and weighed approximately 1.1 metric tons (2,425 pounds). Pretty scary, huh? Not long after dinosaurs went extinct, Titanoboa appeared, seemingly filling the void left by their demise.

9. Sarcosuchus


The Sarcosuchus, nicknamed the SuperCroc, was one of the largest crocodile-like reptiles in history.

©Homo Cosmicos/Shutterstock.com

This giant predator was called SuperCroc, which gives you an idea of its size. Although not technically a crocodile, the Sarcosuchus was its distant relative, the main difference being their size. From the Cretaceous era, Sarcosuchus lived in present-day Africa and South America. It was an imposing 40-foot-long, 10-ton reptile with crocodile-like characteristics. These measurements may seem scary, but Sarcosuchus lived alongside dinosaurs, which means they needed to be big and strong!

8. Arthropleura

Giant Insects - Arthropleura

The Arthropleura is an eight-feet long


that lived during the Carboniferous period.

©FABRIZIO CONTE/Shutterstock.com

Would you ever consider yourself a bug-phobe? If that is the case, then you need to meet Athropleura. This creature is almost identical to the centipede in practically every way, aside from one: its absolutely huge size. Arthropluera was bigger than the centipede, and it had more than 7.5 feet of jointed ribs, making it an extremely large creature. Among all the species of invertebrates ever to exist, Arthropleura was the largest by far.

7. Spinosaurus

Illustration of Spinosaurus on a cliff in front of a full moon

Spinosaurus is a scary extinct animal that was a type of dinosaur and means ‘spine lizard’.

©Daniel Eskridge/Shutterstock.com

During the Middle Cretaceous period, about 93-100 million years ago, Spinosaurus lived in what is now Egypt, Morocco, and the Republic of Niger. In terms of size, the Spinosaurus is the largest carnivorous dinosaur ever discovered! In fact, it was even longer and heavier than the legendary Tyrannosaurus Rex, another famous example of an enormous carnivorous dinosaur. It is estimated that the skull of the Spinosaurus was approximately 6 feet long. Its body could also be over 59 feet long, which is 19 feet longer than that of the Tyrannosaurus Rex. We’re glad to not have to run into this scary extinct animal!

6. Megalodon

Megalodon open mouth

The largest megalodon tooth ever discovered was more than 7 inches long!

©Gil Cohiba/Shutterstock.com

Megalodon was an extinct species of giant shark that lived between 2.8 and 1.5 million years ago. Known as the giant shark, the Megalodon is commonly thought to have looked similar to the modern great white, and its name means “big tooth.”. While great whites can grow to be 20 feet long and weigh as much as 7,000 pounds, Megalodon was estimated to be 60 feet long, weighing as much as 50 tons. It was only 2.6 million years ago that Megalodon died out. As a result, it ate animals that are still around today, like giant sea turtles, porpoises, and whales.

5. Gorgonops


Gorgonops measured approximately 10 feet long and weighed about 1,000 pounds.

©Dmitry Bogdanov / CC BY 3.0 – License

There were plenty of terrifying prehistoric creatures on our planet before dinosaurs ever appeared. A great example is gorgonops, an animal that existed 260 million years ago before dinosaurs became dominant predators. In terms of size, Gorgonops was approximately 10 feet long and weighed approximately 1,000 pounds. In terms of size, it would have been about as large as a small great white shark. Gorgonops may have been warm-blooded, which is one of the most fascinating facts about it. This means it may have had a layer of fur covering it. However, it’s hard to tell because Gorgonops’ pictures show them looking more like lizards than anything else.

4. Phorusrhacidae

Terror Bird Phorusrhacos Computer generated 3D illustration(1)

The Phorusrhacidae was one of the biggest carnivorous birds that ever lived.

©Michael Rosskothen/Shutterstock.com

These deadly extinct animals are known as “Terror Birds” for a reason. Among the largest carnivorous flightless birds, terror birds constituted the family Phorusrhacidae. South America was dominated by them from 62–2 million years ago during the Cenozoic period. It is estimated that their height ranged from 1 to 3 meters (3 to 10 feet). Extinct mammals and marsupials were their main food sources. This is one scary extinct animal that we wouldn’t want to go up against due to its ability to crush skulls and puncture bones with its beak.

3. Megatherium


Megatherium, also known as the giant ground sloth, was an extinct ground sloth from South America.

©Esteban De Armas/Shutterstock.com

The thought of a sloth isn’t the first thing that comes to mind when thinking of frightening monsters. However, the megatherium appeared more like the giant scary cousin to the sloth of the modern age. A fossil of a giant ground sloth measured 240 in (6 m) long and 120 in (304.8 cm) high. However, unlike many of the other scary extinct animals on our list, the giant sloth was pretty chill. Apparently, these animals ate only plant-based food.

2. Meganeura

3D illustration of Meganeura on a white background

Meganeura was one of history’s largest insects, about the size of an eagle.


When you think of a dragonfly, you don’t get scared, do you? You might have a change of heart once you see the sheer size of this one! If you’d been around some 300 million years ago, during the Carboniferous period, Magneura would have stunned you. The biggest difference between the modern dragonfly and the dragonfly of the past was their size.  With a wingspan of nearly 2.5 feet, it was one of the largest insects ever to live on earth. In those days, the Meganeura ruled the skies. It hunted insects as well as larger creatures, like frogs and newts.

1. Arctodus

Illustration of Arctodus near a river

The giant short-faced bear was the fastest running bear in history.

©Daniel Eskridge/Shutterstock.com

Bulldog bears (Arctodus) are an extinct species of bear that were native to North America during the Pleistocene period, about 1.8 million years ago. During that time, Arctodus simus might have been the largest land mammal that ate meat. The last thing we’d want is to meet it and be its next meal! When standing, it reaches heights of 3.5 meters (11.4 feet) and weighs more than one metric ton (2204 pounds). The size of these bears is estimated to be 50 percent greater than that of the largest polar bears recorded in history.

The photo featured at the top of this post is © racksuz/Shutterstock.com

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About the Author

Volia Schubiger is a freelance copywriter and content editor with a passion and expertise in content creation, branding, and marketing. She has a background in Broadcast Journalism & Political Science from CUNY Brooklyn College. When she's not writing she loves traveling, perusing used book stores, and hanging out with her other half.

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