The length of the Thalassomedon’s neck was up to half its body length
Thalassomedon Scientific Classification
Scientific name
Thalassomedon haningtoni
Thalassomedon Physical Characteristics
2.8 tons to 4.4 tons
Thalassomedon Distribition

Thalassomedon is a genus of aquatic reptiles that stayed in The United States and Canada throughout the Late Cretaceous duration. This large animal comes from an order of aquatic reptiles called the plesiosaurs, characterized by their very lengthy necks. Its closest family member is Elasmosaurus, an additional lengthy- necked plesiosaur. Both reptiles come from the family Elasmosauridae. Thalassomedon is understood from a solitary species, Thalassomedon haningtoni Simply 6 samplings have actually been located up until now.

Summary and Dimension

Thalassomedon translates to the ruler  of the sea and it had no competition until the Late Cretaceous period.
Thalassomedon converts to the leader of the sea and it had no competitors till the Late Cretaceous duration.

Ryan Somma/ CC BY- SA 2.0 – Permit

The genus name is originated from the Greek words “Thalassa,” which indicates “sea,” and “medon,” which indicates “leader.” The name converts as leader of the sea, a referral to the large dimension of this plesiosaur genus.

Thalassomedon is the biggest family member, Elasmosauridae. Nonetheless, contrasted to the bigger plesiosaur category like Mauisaurus, it is a tool- sized reptile. Based upon typical price quotes, this reptile had to do with 35.6 feet long. Nonetheless, going by the dimension of the animal’s head, researchers assume it may have been bigger, with a prospective to expand to sizes of as much as 38 feet.

Based upon the recommended size of 35.6 feet, professionals approximate that Thalassomedon haningtoni would certainly have evaluated concerning 9,000 extra pounds. Like various other plesiosaurs, the Thalassomedon had an incredibly lengthy neck. The neck alone depended on 19 feet long with as much as 62 vertebrae.

The head was reasonably little. It was approximately 19 inches long and had large rows of teeth, with every one coming up to 2 inches in size. Thalassomedon relocated with the help of 4 sets of large fins like a huge turtle would certainly. Each fin had to do with 4.9 to 6.6 feet long. Researchers likewise located rocks in its tummy, and several have actually supposed that these rocks were utilized as ballasts to assist floatation in the water.

Diet What Did Thalassomedon Eat?

It was a predator that fed mainly on fish. Nonetheless, the reptile’s diet might have likewise consisted of cephalopods and smaller sized reptiles that stayed in the very same environment. The large teeth of this plesiosaur were adjusted to squashing the exoskeleton of covering- target. Professionals likewise assume the tummy rocks were utilized as gastroliths to assist food digestion.

Environment – When and Where It Lived

This plesiosaur genus survived the North American continent. Thalassomedon lived concerning 95 million years earlier in an old sea called the western indoor seaway. This was a Cretaceous sea that divided The United States and Canada right into 2. The western indoor seaway was superficial, just concerning 600 feet, however had bountiful aquatic life. The ancient sea was cozy and exotic.

Hazards And Predators

The large dimension of the Thalassomedon implied it would certainly have flourished unobstructed in the western indoor seaway for a number of years. There were no straight predators or perhaps significant competitors. Nonetheless, as time advanced right into the Late Cretaceous, brand-new predators started to increase that took on Thalassomedon for food. A few of one of the most noteworthy predators of this duration consist of the Mosasaurs and Tylosaurus.

Discoveries and Fossils – Where It was Located

R. L. Landberg found the very first and just well-known species of the Thalassomedon genus in 1939. He uncovered the fossil in the Baca Region of Colorado. The locate included brief and deep cervical vertebrae numbering concerning 62. The fossil came from a grown-up, and no pectoral or pelvic bar existed. The name haningtoni was designated to the kind specie by Welles in 1943. Fossils have actually likewise been located in the Belle Fourche Development in Montana.

Termination – When Did Thalassomedon Pass Away Out?

Thalassomedon controlled the western inland seaways for a number of million years throughout the beginning of the Late Cretaceous. Nonetheless, their supremacy began to decrease for many years. The loss of this aquatic reptile accompanies the surge of brand-new predators like the Mosasaurs andTylosaurus This recommends that the Thalassomedon possibly since they might not maintain the competitors.

Similar Animals to The Thalassomedon

Similar reptiles to the Thalassomedon consist of:

  • Elasmosaurus: This is a very closely relevant plesiosaur genus that stayed in The United States and Canada throughout the late Cretaceous. With a size of 34 feet, it was a little smaller sized than the Thalassomedon.
  • Tylosaurus: This was an aquatic reptile that likewise lived throughout the late Cretaceous. It was a little bigger than the Thalassomedon and was likewise a much better- adjusted pinnacle killer.
  • Mosasaurus: The Mosasaurus was a substantial aquatic reptile that stayed in the Late Cretaceous and outlasted the Thalassomedon



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