Omeisaurus: The Majestic Sauropod from China’s Middle Jurassic Era

Omeisaurus: The Majestic Sauropod from China’s Middle Jurassic Era

In this article, we’re going to embark on a journey back in time to the Middle Jurassic era to meet a fascinating creature that once roamed the lush forests of what is now China. This creature, known as the Omeisaurus, is a sauropod dinosaur that has captured the interest of paleontologists and dinosaur lovers alike.

The Omeisaurus, whose name means “Omei lizard,” is a testament to the incredible biodiversity and complexity of life millions of years ago. Its discovery has shed light on the rich prehistoric life that once flourished in the region around Mount Emei, where it was first found.

Omeisaurus Key Facts

Omeisaurus pronunciationoh-may-sore-us
Meaning of nameOmei lizard
Type SpeciesOmeisaurus junghsiensis
When it Lived170.3 to 145.0 MYA
PeriodMiddle Jurassic
EpochBajocian to Tithonian
Length46.0 to 66.0 ft
Height13.1 ft at hips
Weight4.4 tons
MobilityMoved on all four
First Discovery1936 by Charles Lewis Camp and Yang Zhongjian
Location of first findSichuan, China
First Described by1939 by Yang Zhongjian
HolotypeVPP V930

Omeisaurus Origins, Taxonomy and Timeline

Artistic reconstruction of Omeisaurus tianfuensis, a long-necked sauropod dinosaur with a long tail, depicted in a standing posture. The dinosaur's body is depicted in a light grey color with a slightly reddish tint on its head.

The “Omei lizard” derives its name from Mount Emei (also written as Omei), a location of great significance in China. This is where its fossils were first discovered. The suffix ‘saurus’ comes from the Greek word ‘sauros,’ which translates to ‘lizard’ or ‘reptile.’

In the grand tree of life, the Omeisaurus belongs to the group of dinosaurs known as sauropods, specifically within the family Mamenchisauridae. Its type species is Omeisaurus junghsiensis. This genus includes eight species: O. changshouensis, O. fuxiensis, O. jiaoi, O. junghsiensis, O. luoquanensis, O. maoianus, O. puxiani, and O. tianfuensis

This herbivorous dinosaur lived during the Middle Jurassic period, specifically from the Bajocian to Tithonian epochs. This places its existence in China during a time when dinosaurs were the dominant terrestrial vertebrates.

Listen to Pronunciation

Discovery & Fossil Evidence

The story of this discovery begins in 1936, when Charles Lewis Camp and Yang Zhongjian unearthed a partial skeleton in Sichuan, China. This initial find was significant, marking the first time the world was introduced to this unique dinosaur.

Mounted skeleton of Omeisaurus on display in a museum, showing the long neck and tail characteristic of sauropods. The skeleton is placed on a sandy base with information panels in the background.
Gary Todd from Xinzheng, China, CC0, via Wikimedia Commons

The skeleton was later described in 1939 by Yang Zhongjian, who officially named it Omeisaurus junghsiensis. The holotype–the specimen used to initially describe the species–is known as VPP V930.

Since this first discovery, more fossils have been found that provide us with a more comprehensive understanding of this fascinating dinosaur. These fossils include bones from various parts of the body across several species, allowing scientists to piece together a more complete picture of its physical characteristics and adaptations.

Omeisaurus Size and Description

Before we delve into the specifics of the Omeisaurus’ appearance and size, it’s important to note that–like all dinosaurs–our understanding of this creature is based on the fossil evidence we have. This evidence gives us a glimpse into the past but there’s always more to learn as new discoveries are made.

Short Description of Omeisaurus

This was a sauropod–a group of dinosaurs known for their large size, long necks, and four-legged stance. Its body shape was typical of this group with a massive body, a long, flexible neck, and a whip-like tail. Also typical of sauropods, it moved on all four legs. Its vertebrae were elongated which contributed to its incredible length. The limbs of the Omeisaurus were robust to support its massive body weight and its tail served as a counterbalance for its long neck.

Size and Weight of Type Species

Size comparison chart showing the silhouette of Omeisaurus tianfuensis next to a human figure for scale. The dinosaur's length is marked as 10 meters, highlighting its enormous size with a characteristic long neck and tail
Slate Weasel, Public domain, via Wikimedia Commons

This was a sizable dinosaur, even among sauropods. Estimates based on fossil evidence suggest that it was around 46.0 to 66.0 feet long. However, the size varied depending on the species of Omeisaurus.

As for its weight, it’s challenging to provide an accurate estimate without complete fossil evidence. However, given its size and comparing it with other sauropods of similar dimensions, it’s likely that it weighed several tons.

The Dinosaur in Detail

The Omeisaurus had a unique set of features that set it apart from its contemporaries. Its incredibly long neck–even for a sauropod–is one of its most distinctive features. This long neck likely allowed it to reach vegetation that other herbivores couldn’t in order to give it a unique advantage in its environment.

Another notable feature of this dinosaur is its vertebrae. The vertebrae in its neck were elongated, contributing to its neck length. These vertebrae were also hollow to reduce the weight of the neck and make it more easily supported.

The large number of individual fossils recovered indicates that it was a successful design that was well suited to its environment. This success is a testament to the adaptability and survival instincts of this dinosaur, allowing it to thrive in a world filled with other formidable dinosaurs.

The Omeisaurus in its Natural Habitat and Environment

This herbivore lived in what is now Sichuan Province in China–a region that, during the Middle Jurassic era, was likely quite different from the landscapes we see today. The climate was likely warm and humid, supporting lush vegetation that the Omeisaurus would have fed on.

As a large herbivore, its size would have had a significant impact on its environment. It would have needed a substantial amount of food to sustain itself and its feeding habits could have shaped the vegetation patterns in its habitat. Its role as a food source for large predators would also have had an impact on the ecosystem.

Its social behavior is unknown, but like many sauropods, it may have lived in herds for protection. The Omeisaurus, with its size and lifestyle, would have been a major player in its ecosystem, shaping and being shaped by the world around it.

Interesting Points about Omeisaurus

  1. This dinosaur had one of the longest necks of any dinosaur, even among sauropods.
  2. Its name, “Omei lizard,” is derived from Mount Emei where its fossils were first discovered.
  3. It is part of the family Mamenchisauridae, which includes other long-necked sauropods.
  4. The large number of fossils found suggests that it was a successful species in its environment. There are eight species of Omeisaurus.
  5. It lived during the Middle Jurassic period, a time when dinosaurs were the dominant terrestrial vertebrates.

Contemporary Dinosaurs

In the lush, prehistoric landscapes of China where the Omeisaurus once roamed, a symphony of life played out with each creature contributing its own unique note. Among these were the Asian dinosaurs Mamenchisaurus, Shunosaurus, Tuojiangosaurus, and Yangchuanosaurus. Each of these contemporaries of the Omeisaurus were a part of the same vibrant ecosystem.

The Mamenchisaurus, with its extraordinarily long neck, was a sight to behold. Yet, despite its imposing size, it was a gentle giant much like the Omeisaurus. Both herbivores may have grazed side by side, their long necks reaching for the succulent leaves of towering trees. The Shunosaurus was another considerably smaller herbivore. Despite this smaller size, it had an impressive clubbed tail that it could use to deter predators.

The Tuojiangosaurus, with its rows of bony plates and spikes, was another fascinating contemporary. While it was an herbivore like the Omeisaurus, its formidable defensive features set it apart. The Omeisaurus lacked such defenses and might have relied more on its size and possibly the safety of numbers to deter predators like the Yangchuanosaurus.

Among the predators of this time, the Yangchuanosaurus stood out. This carnivorous dinosaur was a stark contrast to these peaceful herbivores. It might have seen the Omeisaurus and its contemporaries not as fellow inhabitants of the same ecosystem, but as potential prey. The presence of such a predator would have undoubtedly influenced the behavior of the Omeisaurus, perhaps leading it to move in herds for protection.

In this ancient world, the Omeisaurus, Mamenchisaurus, Shunosaurus, Tuojiangosaurus, and Yangchuanosaurus each played their part. Their lives were intertwined in a complex dance of survival, a testament to the rich diversity and intricate balance of the dinosaur era.

List Of All Dinosaurs

We have created a list of all dinosaurs we have covered here, sorted across the seven main groups of dinosaurs. We also include information about their type of diet, (omnivore, herbivore or carnivore) and the time they lived.

Frequently Asked Questions

What does the name mean?

The name means “Omei lizard,” derived from Mount Emei where its fossils were first discovered, and ‘sauros,’ a Greek word for ‘lizard’ or ‘reptile.’

When did this dinosaur live?

It lived during the Middle Jurassic period, specifically from the Bajocian to Tithonian epochs, which is between 170.3 and 145 million years ago.

What did the Omeisaurus eat?

It was an herbivore, meaning it ate plants. Its long neck would have allowed it to reach vegetation that other herbivores couldn’t.

How big was this dinosaur?

It was a sizable dinosaur with estimates suggesting it was around 46.0 to 66.0 feet long. However, its weight is harder to estimate without complete fossil evidence.

Where were the fossils found?

Fossils were first discovered in Sichuan, China, in 1936 by Charles Lewis Camp and Yang Zhongjian.

What made the Omeisaurus unique?

It had a particularly long neck, even among sauropods. Its vertebrae were elongated and hollow, which contributed to its neck length and reduced the weight of the neck.


Please note that the information in this article is based on various sources, drawing on scientific research, fossil evidence, and expert analysis. The aim is to provide a comprehensive and accurate overview of the Omeisaurus, but please be aware that our understanding of dinosaurs and their world is constantly evolving as new discoveries are made.

This article was last fact-checked: Joey Arboleda, 06-12-2023

Featured Image Credit: Levi bernardo, CC BY-SA 3.0, via Wikimedia Commons