Cryptoclidus is a type of plesiosaur, a group of extinct marine reptiles that roamed the seas during the Mesozoic era. These creatures were mainly characterized by their long necks, broad flippers, and streamlined bodies.

 Cryptoclidus lived during the Late Jurassic period, around 160 to 145 million years ago, and they were medium-sized plesiosaurs, measuring up to 4.5 meters (14.8 feet) long. However, it was in 1892 when Harry Govier Seeley named it ‘Cryptoclidus.’

This name might not sound extraordinary, but it raises eyebrows when translated into English. It means ‘hidden clavicles.” These terms refer to small clavicles hidden in the front limb girdle.

Besides the name, the remaining adult and juvenile skeletons of this creature provide valuable information about this fascinating creature’s anatomy, behavior, and ecology. Useful fossils of these extinct reptiles have been found in sedimentary rocks throughout South America, Northern France, England, and Russia. So, cryptoclidus is an essential part of the fossil record and continues to captivate the imagination of scientists and laypeople alike.

Appearance

The fossil records suggest that cryptoclidus had a streamlined body, a long neck, and four flippers. Its head was relatively small, and its jaws had pointed teeth. The neck comprised 38 vertebrae, which was pretty long for a plesiosaur.

Moreover, the vertebrae were elongated and had a relatively low neural spine. This feature allowed cryptoclidus to move its neck more freely than other plesiosaurs.

Cryptoclidus had a streamlined body, a long neck, and four flippers
Cryptoclidus had a streamlined body, a long neck, and four flippers


Habitat

Cryptoclidus lived in the shallow seas that covered much of Europe during the Late Jurassic period. The fossils of cryptoclidus have been found in England, France, Germany, and Russia. During this time, the climate was much warmer than today. At the same time, sea levels were much higher. The shallow seas provided an abundant food source for marine reptiles like cryptoclidus.

Some experts argue that cryptoclidus spent much of their time on land and only went into the water to feed. However, concluding that land movement was possible for this reptile is practical. As we’ve said, their long necks, broad flippers, and streamlined bodies were adapted to allow them to move more gracefully in the water.

The presence of Cryptoclidus fossils in various sedimentary rocks suggests it was a versatile predator that adapted to different marine environments.

Diet

A straightforward way to know Cryptoclidus’ diet is to consider that their fossils have been found in sedimentary rocks deposited in environments ranging from lagoons and estuaries to open oceans. These environments would have provided the ideal conditions for cryptoclidus to feed on its preferred prey.

Besides that, its pointed teeth were ideal for catching slippery prey, and its long neck allowed it to reach further into the water to grab its food.

From these details, we can assert that cryptoclidus was a carnivore and fed on various small marine animals, such as fish, squid, and crustaceans.

Reproduction

Like other reptiles, cryptoclidus likely laid eggs and buried them in sand or gravel on the shore. The hatchlings would have had to fend for themselves, as there is no evidence of parental care in plesiosaurs.

Threats

Cryptoclidus went extinct at the end of the Cretaceous period. This term is usually used when referring to approximately 66 million years ago. What is the exact cause of their extinction? No one has the answer currently. However, after analyzing this group of animals and their ecology, we can strongly suggest that a combination of factors, including climate change, volcanic activity, and the impact of a giant asteroid, were responsible. Other threats that cryptoclidus might have faced during the Late Jurassic period are excessive predation from other marine reptiles and competition for food.

One of the main reasons why Cryptoclidus went extinct may have been changes in the climate and sea level, which affected their food sources and breeding habitats
One of the main reasons why Cryptoclidus went extinct may have been changes in the climate and sea level, which affected their food sources and breeding habitats


Facts About Cryptoclidus

  1. Cryptoclidus was a medium-sized plesiosaur that lived during the Late Jurassic period.
  2. They measured up to 4.5 meters (14.8 feet) in length.
  3. Cryptoclidus had a streamlined body, a long neck, and four flippers.
  4. Their pointed teeth were ideal for catching small marine animals.
  5. Cryptoclidus lived in the shallow seas that covered much of Europe.
  6. The fossils of cryptoclidus have been found in England, France, Germany, and Russia.
  7. Plesiosaurs must have reproduced through the laying of eggs.


FAQs

What is the difference between cryptoclidus and other plesiosaurs?

Cryptoclidus belongs to the family Cryptocleididae, distinct from other families of plesiosaurs. It had a long neck, which comprised more vertebrae than other plesiosaurs. Additionally, cryptoclidus had relatively small flippers, which would have been used more for steering than propulsion. So, there is a possibility that many plesiosaurs were better swimmers than cryptoclidus.

Where have fossils of cryptoclidus been found?

Fossils of cryptoclidus have been found in England, France, Germany, and Russia. The first specimen was discovered in the Oxford Clay Formation in England in 1851. Since then, archeologists have discovered more specimens that give us a better understanding of the anatomy and behavior of this marine reptile in different parts of the world, especially Europe. However, scientists are still looking for more fossils.

How did cryptoclidus swim?

Cryptoclidus swam by moving its four flippers in a coordinated motion, much like modern sea turtles. Its flippers were relatively small compared to other plesiosaurs. This suggests it could have been a slower swimmer. However, its streamlined body and long neck would have allowed it to move through the water easily.

How do we know what cryptoclidus looked like?

We know what cryptoclidus looked like from the fossils that have been found, which include bones, teeth, and sometimes even skin impressions. Scientists can examine the fossils and reconstruct the animal’s anatomy. They can also make educated guesses about the animal’s behavior and ecology. Additionally, paleoartists can use their extensive knowledge of the anatomy of extinct animals to create realistic depictions of the animal’s appearance.

Are there any living relatives of cryptoclidus?

Yes, there are relatives of cryptoclidus that are alive today. Turtles and crocodiles are some of the best examples. The two reptiles share a common ancestor with plesiosaurs. However, you can’t find close relatives. All the species, like Cryptoclidus eurymerus, Cryptoclidus oxoniensis, and Cryptoclidus brachypterygius, went extinct millions of years ago.

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