Nothosaurus is a genus of marine reptile belonging to the group Sauropterygia. It lived during the Triassic period, approximately 245 to 230 million years ago. The first fossils of Nothosaurus were discovered in Europe in the 19th century, primarily in Germany and Switzerland. Since then, additional findings have provided paleontologists with valuable insights into this enigmatic marine reptile.

Nothosaurus was a medium-sized marine reptile, measuring around 10 to 13 feet (3 to 4 meters) in length. Its body was well-adapted to life in the water, with streamlined features and limbs modified into paddle-like structures for efficient swimming.

One of the most distinguishing features of Nothosaurus was its elongated neck, which allowed it to reach and capture prey in the water with precision. Its jaws were equipped with sharp teeth, suited for catching fish and other marine creatures. Its large eyes and keen senses likely helped it navigate and locate food in the underwater environment.

Nothosaurus is the most well known nothosaur to exist. It had a long narrow snout coupled with a long neck and fang-like teeth. Small teeth lined its jaws all the way to the back of the cheek region. It had longer pointy teeth in the front of its snout and smaller teeth at the back of its jaw. Nothosaurus had tall vertebral spines in the shoulder region and powerful limb muscles attached to the underside of its body. Unlike plesiosaurs, nothosaurs had flexible knee and ankle joints.

Eight species of nothosaurus have been found in Europe and the Middle East. In the early triassic period a rise in sea levels allowed nothosaurus to invade a shallow sea in what is now known as Israel. New species of nothosaurus evolved there, including a specialized dwarf species.

Its fossils have been discovered in sea rocks, indicating that it was a sea going dinosaur but they probably rested and bred on land - like modern day seals.