Prehistoric waters were home to a wide variety of amazing creatures, including ancient sharks. These sharks used to live for millions of years, but habitat changes, lack of prey, and other evolutionary factors made it impossible for them to exist to this day.
We mainly find these extinct sharks through their teeth, which they have raised in large numbers throughout their lives and which last better than the cartilage on the rest of their body.
However, sharks are still strong as a species, and they remain some of the oldest creatures on Earth!
Unfortunately, overfishing has put more than a third of today’s sharks at risk, so the fight is not over yet. We need to help cut down on overfishing and climate change before it’s too late so that many more sharks are added to this list of 11 extinct sharks.
Read on for top facts about the most interesting extinct sharks.
1. Megalodon
Megalodon is the largest shark ever to exist. Its length was 49-59 feet (15-18 meters), as judged by the size of its massive teeth.
Megalodon translates to “big tooth,” and these teeth have helped researchers learn a lot about the animal, from its size to what it ate. The entire megalodon skeleton has never been found intact.
The species survived for over 16 million years and became extinct about 2.6 million years ago. During their heyday, they flourished all over the world, and their teeth have been found on almost every continent! (The exception is Antarctica.)
We don’t know for sure what killed the Megalodon all those years ago, but it was probably a cooling of the planet. These sharks lived in warm waters and the cooling of the ocean would reduce their habitat and prey.
2. Cladoselache
The next shark on our list is much smaller. Kladoselach sharks were only 4 feet (1.2 meters) in size! Their bodies were different from other sharks of the time, but perhaps they were ideally suited to rush through the water for prey.
They had very few scales and no clasps (organs that are used to transfer sperm from male sharks to female sharks). How they reproduced is not known for certain, but they have lived in the waters of North America and Europe for over 100 million years.
Their disappearance took place about 250 million years ago.
3. Stetacanthus
Another small shark, stetacanthus, has grown to 3 feet (1 meter) in length. Its name, which translates as “pectoral thorn”, comes from the flat projection on the back of male sharks.
It is believed that they used it to attach to female sharks when mating. It also slowed down their movements significantly. Stethacanthus most likely fed on the bottom rather than fast predators.
They lived in North America, Asia and Europe. The species died almost 300 million years ago.
4. Ortacanthus
Ortacanthus is a freshwater shark native to Europe and North America. Its hallmark was a thorn sticking out of its head, believed to scare away predators and may even be poisonous!
It hid in the densely leafy waters, which served as excellent hunting grounds for stealthy predators.
Orthancantus sharks moved through these waters with long, flexible bodies that could pass through narrow crevices. For this reason, they are sometimes called the “eel shark”.
They became extinct about 260 million years ago.
5. Xenacanthus
Xenacanthus is a miniature eel shark. At about 3 feet (one meter) long, it was only a third the size of Orthancantus.
The two sharks lived next to each other, with Xenacanthus likely feeding in hard-to-reach places between plants or the ground. They did not compete with each other, but instead ate prey of different sizes.
Having lived a little longer than its counterpart, Xenacanth became extinct just over 200 million years ago.
6. Gibodus
These sharks were small and fast, designed to chase prey at maximum speed. They had small horns at the top and compact bodies measuring 6-8 feet (2-2.5 meters) in length.
They lived in shallow waters and ate their prey with bites, twisting their heads, tearing it to pieces.
Gibodus died out 65 million years ago. The most common hybrid fossils are teeth and spines.
7. Ptikhod
The bird lived about 85 million years ago. This carnivore fed mainly on molluscs and molluscs, whose teeth were adapted to pierce hard shells.
Although today this diet is mostly eaten by small sharks, the Ptychodus sharks fed on the much larger ancestors of these animals.
These include the 9-foot (2.7-meter) Platyceramus clam and the 2-meter Inoceramus clam.
Approximately 33 feet (10 meters) long, the Ptychodus sharks were among the largest known sharks in the ocean at the time. Genetically, they were very closely related to modern sharks!
8. Cretoxirin
These sharks lived around the world approximately 80 million years ago. They competed with pliosaurs and mosasaurs for food, as they all ate large prey.
One of these victims, a 20-foot fish named Xiphactinus, was found undigested inside the fossilized cretoxirin.
Cretoxirin was not at the top of the food chain, however, as it was hunted by larger sea creatures such as the reptile Tylosaurus.
These sharks were larger than the great white shark, reached 26 feet (8 meters) in length, and were also incredibly fast – they could move at 43 miles (70 km) per hour! If they were alive today, they would be the fastest shark in the world.
9. Success
The Edestus shark, also known as the scissor shark, lived over 300 million years ago.
Their teeth grew differently from modern sharks, forming a single line from the back of the mouth to the front. As new teeth grew in the back of their mouth, new teeth pushed outward.
The lack of fossils in shark bodies leaves many questions unanswered. They most likely hunted by cutting or impaling prey with their unique teeth, but what exactly they ate is unknown.
One theory is that sharks were specialized hunters. If this were the case, the death of their victim could lead to their own disappearance.
11. Scapanorhynchus
Scapanorhynchus became extinct just over 5 million years ago. Before that, they swam in the Atlantic Ocean for over 140 million years.
They had long, pointed muzzles and teeth designed to catch and tear apart prey, but most sharks of this genus were incredibly small! Most of the species measured just over 2 feet (65 cm).
Scapanorhynchus sharks hunted, hiding in the depths of the ocean, patiently waiting for the prey to pass by. They were not fast swimmers and therefore were rather passive hunters!
These sharks are very similar to the goblin sharks that live today, but some key changes set them apart, including their fins.
12. Anisopleurodontis
Anisopleurodontis is a genus of sharks, but there is only one species of this genus! They became extinct nearly 300 million years ago and were closely related to rat fish.
They are believed to be about 6-10 feet (2-3 meters) long, with large heads and mouths. Unlike modern rat-catchers, Anisopleurodontis could only eat fish. It is also possible that their diet consisted of fish and refined prey.