Nothosaurus were a species of Sauropterygian reptiles that lived between 200-241 million years ago, in the Triassic era, featuring remains found from Northern Africa, Europe, and Asia. Their scientific name derives from the ancient Greek words “Nothos,” which means false, and “sauros” which means lizard.

Most notably, since they retained their distinct land characteristics despite being well-suited to marine life, Nothosaurus is sometimes called the seal of the Triassic era. This would mean that Nothosaurus would reside along the coastline and be able to plunge into the water in pursuit of food.

Featured Image Credit: Nobu Tamura


Around 13 feet in length, featuring long, bunched-up digits and maybe a tail section, Nothosaurus was a quasi-marine animal. The Nothosaurus genus includes roughly 12 species, a few of which could reach twice the length. 

Nothosaurus had nostrils located near the top of their snout
Nothosaurus had nostrils located near the top of their snout, which suggests that they may have spent most of their time at or near the surface of the water

Credit: Internet Archive Book Images

Nothosaurus would move through the sea by using its tail, limbs, and webbed flippers, while the wide, flat cranium had long, needle-toothed molars that were likely used to catch fish and other aquatic life. The Nothosaurs’ tight palate, which divided the food tubes from the air passageways, was an adaptation that made it easier for them to consume prey when submerged in water. Nothosaurus descended from terrestrial reptiles that were strongly linked to serpents and lizards, comparable to other sauropterygians.


Nothosaurus were carnivores, and they preferred piscivore diets. Long, narrow canines protruded from Nothosaurus’ mouth while the animal’s jaws remained clenched and intertwined with one another. These jaws created a reliable prey snare that could be used to capture fish and other slick creatures. Despite the widespread perception that Nothosaurus was a voracious fish consumer, it’s possible that it’s also taken on smaller and younger aquatic amphibians. The discovery of young placodonts like Cyamodus inside the gut of the considerably lesser Nothosaur provides evidence for this hypothesis.


According mostly to fossils found, Nothosaurus is thought to have resided in present-day North Africa, Asia, and Europe. Although the precise environment of these reptiles is unknown, they were thought to be quasi-oceanic reptiles and belonged to that group, suggesting that they may have lived in maritime settings.

Fossils of Nothosaurus have been found in several different locations around the world
Fossils of Nothosaurus have been found in several different locations around the world, including Germany, Switzerland, China, and Canada

Credit: paleobear

Taking from other present-day semi-marine animals, Nothosaurus most likely would resort to habituating coastlines and protruding rock formations like seals do. In terms of ability to reach the depth or estimate the distance they could cover while being in the sea is currently unknown due to a lack of sufficient evidence.


It is believed that the Nothosaurus subspecies from the Triassic era reproduced sexually, like other reptiles, and it is probable that they once gave birth to live offspring. While Nothosaurus thrived on land, it is still unknown whether it laid eggs or gave birth to live offspring. 

Live birth appears to be the norm in Ichthyosaurs and potentially the subsequent Plesiosaurs, which are believed to have descended from Nothosaurus, according to fossil evidence of Nothosaurus from some of the other families. Yet, it is still unclear when live births began to happen in aquatic reptiles.


Nothosaurus went extinct 200-something million years ago. Although the precise cause is unknown, it is thought that this species went extinct as a result of a widespread extinction event that occurred during the Triassic-Jurassic era. Changes in temperature affect the availability of food supply which in turn directly affects the thriving element of species. The supply of food may not have been enough to support the Nothosaurus species.

Nothosaurus went extinct 200 million years ago as a result of a widespread extinction event
Nothosaurus went extinct 200 million years ago as a result of a widespread extinction event

Credit: Internet Archive Book Images

In terms of direct threats and predators, the Nothosaurus was beset on all sides. Nothosaurus spent most of its existence on shore and certainly never far enough to lose track of both the water and land. By coming back to land, Nothosaurus could avoid marine adversaries like sharks and even Ichthyosaurs. Yet, if archosaur reptiles had been able to access the same coastal regions as Nothosaurus did, they might have been a danger, and the land could not have been completely secure.

Facts about the Nothosaurus 

  1. Nothosaurus was a family of 12 types of species.
  2. Nothosaurus are compared to present-day seals.
  3. Nothosaurus could isolate feeding tubes from breathing ones to eat underwater.
  4. Nothosaurus are distant relatives to modern-day reptiles such as snakes.
  5. Nothosaurus would weigh anywhere around 170-300 lbs.


Was Nothosaurus a social or solitary species?

As of this moment is yet to be determined if Nothosaurus were social or solitary species, but one thing is almost certain when it came to reproducing, Nothosaurus specimens would seek out one another in order to mate, and there is no clear evidence to claim either fact.

Could Nothosaurus walk on land?

The Nothosaurus, who descended from terrestrial animals, were fish predators. Some of them possessed clawed digits, indicating they could indeed move on land, indicating they weren’t entirely accustomed to aquatic life.

Why did the Nothosaurus go extinct?

Sadly, Nothosaurus became extinct in the Late Triassic era, about 200 million years ago. Although the precise reason for its demise is uncertain, additional predators or a reduction in food availability are two possibilities. Like many that followed it, such as dinosaurs, the required resources to fulfill such needs were incompatible with what the environment could offer.

How mobile was the Nothosaurus on the sea and land?

Nothosaurus ranged anywhere between 13-23 ft and would weigh 170-300 lbs. Considering the anatomical composition, it is presumed that it wasn’t particularly fast either on land or at sea. While some species sacrifice the ability to shift environments to excel in one, the Nothosaurus was moderate in both environments.

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