Plesiosaur and Belemnite marine animals, illustration
Plesiosaur and Belemnite marine animals, illustration


Plesiosaurus, a marine reptile from the Jurassic period, belonged to the group known as plesiosaurs. Despite coexisting with numerous dinosaurs, it is important to note that Plesiosaurus itself was not a dinosaur. Its discovery dates back to 1821 when the first fossil was found.


Characterized by its aquatic nature, Plesiosaurus utilized four fins and a short, wide tail for movement. It boasted a distinctive serpentine neck, almost as long as its body, with a small head at the end. Typically, fully grown individuals measured around 11 feet in length.

Facts about Plesiosaurus

  • Existed from 228 million years ago to 61.6 million years ago.
  • Inhabited marine environments.
  • Functioned as a carnivorous predator.
  • Engaged in live birth for reproduction.
  • Paleontologists have discovered a total of 938 different specimens.

Artistic Representations and Mythology

In artistic representations, many artists do not distinguish between the various types of Plesiosaur. Furthermore, depictions of Plesiosaurus often incorporate elements influenced by cryptozoological mythology surrounding creatures like the Loch Ness Monster.


Plesiosaurus, a fascinating marine reptile from the Jurassic period, offers insights into the diverse ancient ecosystems that once existed. Its unique features and role as a predator make it an intriguing subject of study for paleontologists.