This Ancient Whale Sized Fish Was a “Suction Eater” Without Teeth

Written by Emilio Brown
Published: December 26, 2022
© [email protected]_Dmitry Bogdanov/CCBYSA3.0
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The ocean is one of the earth’s greatest mysteries, and within it lies life that comes in many sizes and appearances. Even with the technology we have today the majority of the ocean remains undiscovered, and unknown by mankind. Around 80% of the ocean has been unexplored, with amazing life to be found at all depths. Across earth’s history, there have been countless giants, and here you will learn about the ancient whale-sized fish that once swam in the sea.

The blue whale is currently the largest animal on earth. Having an age estimated to be 4.5 billion years old, the earth has had countless species of massive sizes. Fossil evidence and in-depth research have allowed us to learn about extinct animals, and here you will discover one of the many ancient beasts that swam earth’s waters.

The Shastasaurus

Shastasaurus in the water
Shastasaurus is a cross between a dolphin and a lizard.

©[email protected]_Dmitry Bogdanov/CCBYSA3.0

The Shastasaurus is an extinct genus that lived during the Triassic period. While dinosaurs and large reptiles ruled the land, the Shastasaurus lived in the ocean. Despite their appearance and aquatic lifestyle, the Shastasaurus was not a fish. They were ichthyosaurs, which are dolphin-like marine reptiles. Fossil evidence has helped identify over 100 different species of ichthyosaurs, and the Shastasaurus is the largest of them all. 

Shastasaurus have been reconstructed using their fossil remains, and today three species have been identified. Shastasaurus pacificus was the first described in this genus. Their discovery occurred in the early 1900s in Shasta County California by John C. Merriam with the help of his expedition party.

S. pacificus, S. sikkanniensis, and S. liangae are the three species of Shastasaurus. As more discoveries occur, there may be reclassifications. Other Ichthyosaurs and fossils of other members of the Shastasauridae family are sometimes confused for the Shastasaurus. Fossils have helped us learn more about the species, but can also confuse paleontologists.

The Shastasaurus: Appearance

The different species of Shastasaurus varied in size, but all were very big. The largest of them all was S. sikanniensis, which grew up to 69 ft. in length and weighed 89.8 short tons (179,600 lbs). The type species S. pacificus was smaller but still grew up to 23 ft. in length, and had a mass of 1.7 short tons (3,400 lbs). 

Compared to other Ichthyosaurs, the Shastasaurus had a slender appearance, and it is not yet known if they had a dorsal fin. Their bodies are similar to dolphins, mixed with a lizard. Fins helped them swim, and their snouts were very short and toothless. Their size matched the largest whales, and the Shastasaurus also lacked gills and breathed air like them. 

Fossils found around the world are what were used to construct how this species looks. At first, they were depicted as much stockier, but the discovery of S. liangae fossils in China helped get a more accurate depiction.

The Shastasaurus: Diet and Method of Hunting

Along with having a very short snout, the Shastasaurus lacked teeth. Their mouths were adaptive to fit their diet and resemble the ichthyosaur Shonisaurus. Shastasaurus was a suction feeder, and it used its mouth like a vacuum. The shortness of their jaw made it easier to open their mouths in the water and allowed them to create vacuums quicker. 

Small fish and soft-bodied cephalopods are what these large animals survived on. Because of their giant size, they were able to hold their breath and dive to extreme depths. The tail of this giant is less developed than other Ichthyosaurs, meaning they were slow swimmers. Cruising is likely what this animal did, feeding on prey that gets near.

The Shastasaurus: Habitat

Fossils remains of the Shastasaurus have been uncovered around the globe from California to China. Most of the fossils of this animal were found near the Pacific Ocean coastlines. Being so large, the Shastasaurus was able to dive deep into the waters. Fish of all sizes, sharks, rays, sea urchins, mollusks, large reptiles, and various other life filled the ocean along with the Shastasaurus.

During the time of their existence over 200 million years ago, the waters and the land masses looked very different than today. Pangea was the only continent at the beginning of the Triassic period, and it was surrounded by the giant ocean Panthalassa. By the Mid-Triassic era, the supercontinent began to break apart forming the two massive continents Gondwana, and Laurasia.

Shastasaurus was one of the many reptiles that reigned during the Triassic period, and it is believed they went extinct at the end of their period right before the Jurassic age. There are lots of amazing giants that lived on land and sea across earth’s history, and fossils help humans learn more about them. 

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Shastasaurus in the water
© [email protected]_Dmitry Bogdanov/CCBYSA3.0

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About the Author

Spiders, snakes, and lizards are my favorite types of animals, and I enjoy keeping some species as pets. I love learning about the various wonders nature has to offer and have been a writer for 5 years. In my spare time, you can find me getting out into nature.

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