The Megalosaurus was one of the most ferocious dinosaur genera you can imagine. These large and ferocious dinosaurs inhabited our planet during the Jurassic Period (about 166 million years ago). This genus is classified within the group of the megalaurid theropod dinosaurs.

This genus would have looked as ferocious as you can imagine. It had large, sharp claws and equally sharp teeth that could easily tear apart prey much larger than themselves.

Despite having all the makings of a great candidate for being a ferocious predator, it is suspected that it could have been simply a scavenging dinosaur.

Do you want to know more about this specimen? Below you will find the most complete information about the Megalosaurus you can imagine… Keep reading and discover everything about the carnivorous dinosaur of the Jurassic period!


Basic information about the Megalosaurus

The Megalosaurus was undoubtedly a great dinosaur as its name indicates and also a predator. Let’s see what the characteristics of Megalosaurus are.

How long is it? – The length of this dinosaur is approximately 9 meters.
What is its height? – Megalosaurus was between 3 and 4 meters long.
What is its weight? – The approximate weight of this predatory dinosaur is 2 tons.
When did it live? – It inhabited the Earth about 166 million years ago.
What is its family? – It belongs to the family Megalosauridae.

The taxonomy of the Megalosaurus

Kingdom Animalia > Filo Chordata > Superorder Dinosauria > Order Saurisquia > Suborder Theropods > Family Megalosauridae > Subfamily Megalosaurinae > Genus Megalosaurus

Megalosaurus species

So far there is only one species in the genus Megalosaurus. The only species discovered is M. bucklandil.

The family: megalaurids

The Megalosauridae are a family of dinosaurs made up of carnivorous theropod dinosaurs. It is a family that comes from the Order Saurisquia. The families that most resemble these dinosaurs would be the Allosauridae and the Spinosauridae.

The Megalosauridae are a family that includes several groups of dinosaurs, among them the Torvosaurus, Eustreptospondylus, Streptospondylus and the one we are talking about in this entry: the Megalosaurus.

For the first time, in 1824, a dinosaur is formally described, and thanks to this, the dinosaur clade is created. This is the description of the Megalosaurus.

However, even though the Megalosaurus was described in 1824, it was not until 1869 that Thomas Huxley first defined the family of Megalosauridae.

Did you know that? – The role of this family throughout history has been that of a “dustbin” for those dinosaurs that were either partially described or not identified. When paleontology was just starting, up to 48 species were grouped together within this family. Little by little the species were classified correctly.

Characteristics of the family

This family is distinguished from the others by something quite clear: two synapomorphs (unique characteristics of a group). The first is a deltopectoral one: the humeral diaphasis contains a humeral crest that ends halfway. The second is the fibula, which is missing an anterolateral tuber.

An important characteristic of this family of dinosaurs is that it has a more elongated and less high skull. The ratio of length to height is 3 to 1.

The large body size of this theropod dinosaur does not prevent it from being a biped animal. They came to weigh about a ton, and even more. According to the samples obtained in the Early Jurassic and those obtained from the end of the Middle Jurassic, it has been deduced that the Megalosaurus increased in size as they evolved.

The increase in size over time resembles the pattern followed by other theropod giants such as Spinosauridae.

The teeth of the Megalosauridae have some differences from those of the other theropods. For example, their teeth have multiple wrinkles in the enamel near the hinge area and a sharp edge.

Location and period

Within the Middle Jurassic, it is one of the largest carnivorous dinosaurs known and has one of the best preserved femurs.

The megalaurids are classified as a European dinosaur group, although they have been found in Niger. It has been considered the possibility that this family of dinosaurs appeared shortly before the Pangaea subdivision (in the Gondwana and Laurasia areas). Therefore, there is a possibility that this family of dinosaurs would have dominated both halves during the Jurassic period.

Description of the Megalosaurus

Having made a little bit clear about the family, it is time to see the characteristics of the Megalosaurus.

Unlike most of their family, Megalosaurus were initially depicted as four-legged animals. This means that they used their four legs to walk properly (but we now know that they were typically bipedal).

The first descriptions according to Buckland

At first, not much was known about this dinsoaur, as hardly enough remains had been found. Still, Buckland would have made a description of this dinosaur from a reconstruction.

Even though the family of this dinosaur is mostly bipedal, Buckalnd reconstructed the Megalosaurus as four-legged animals, meaning that they used their four legs to move around.

Buckland also thought it was an amphibious animal, which would be an animal that is capable of both swimming in the water and walking around the continent.

The estimated length of this dinosaur was forty feet long and its weight would come to be around 1000 kilograms.

Current description of the Megalosaurus

This great dinosaur was once considered the most typical. Because of this, the above mentioned thing happened, classifying all the dinosaurs into this genus.

The skeleton of this genus is not completely reconstructed. So far, no complete skeleton has been found on this dinosaur.

The size of this dinosaur comes from Owen’s estimate in 1841 that it would be about 30 feet long. A totally accurate figure cannot be given because no articulated dorsal vertebral series have been found yet, making it difficult to estimate.

The weight of this dinosaur was estimated by Gregory S. Paul in 1988, leaving it at 1100 kilograms. This approximation of its weight was made based on a thigh bone that was seventy-six centimeters long. Later estimates, approximate the ton as JF Anderson’s extrapolation method that estimates the weight at 943 kilograms.

The skull of the Megalosaurus is not fully known. The few skull remains found are mostly quite large compared to the rest of the body. This could indicate that this dinosaur would have had an extraordinarily large head.

The lower jaw of this dinosaur is quite robust. Seen from above it is completely straight, which suggests that its jaws were narrow.

The shape of the profile of the muzzle cannot be deduced if it was curved or rectangular because no praemaxilia has been found yet. However, the frontal branch of the jaw is relatively short, suggesting that the muzzle is rather chubby in shape.

The spine probably had ten vertebrae in the neck, five sacral vertebrae, thirteen dorsal vertebrae and fifty to sixty vertebrae in its tail.

The scapula or shoulder blade is wide and short, its length is about 6.8 times the minimum width approximately.

The humerus is very robust with its lower and upper ends very expanded. One of the remains (specimen OUMNH J.13575) measured approximately 388 millimetres.

The ulna is extremely robust, much more corpulent than any other known dinosaur. According to specimen BMNH 36585 (the only one discovered), the length is 232 millimeters and the circumference of the axis is at least 142 millimeters. When viewed from the front, it is straight and has a large olecranon.

The iliac bone of the pelvis is long and low, with a convex upper profile. The blade

When and where did this dinosaur live?

Many, many years, millions of years ago, dinosaurs lived on Earth. The era that dinosaurs lived in is called the Mesozoic Era.

Within the Mesozoic Era, which began 251 million years ago and lasted 186 million years, we find 3 subdivisions in periods: Triassic. Jurassic and Cretaceous (from older to more recent). The Jurassic period began 200 million years ago and lasted 56 million years.

Within the Jurassic period there are three periods: Early or Lower, Middle and Upper or Late (from older to more recent).

The Megalosaurus inhabited 166 million years ago, in the Middle Jurassic Mesozoic. We can specify this much by adding at the end that it was in the Bathonian Age.

Where did Megalosaurus live? – This carnivorous dinosaur would have lived in the area we know today as Europe.

In 2010, Benson comes to the conclusion that with its size and distribution, Megalosaurus would have been the largest predator in its area.

What do Megalosaurus eat?

As mentioned above, Megalosaurus was a predatory dinosaur. Their goal was to catch another defenseless dinosaur to eat it as a carnivore.

The Megalosaurus was a carnivorous dinosaur with a lot of appetite. Living in the Jurassic Period, probably their daily menu was Stegosaurus and Sauropods. It is also possible that it hunted Iguanodon dinosaurs, although there are some doubts about this (Iguanodon belong more to the Lower Cretaceous).

The Megalosaurus were really big and carnivorous too, so it was deduced that he could have hunted other dinosaurs without any problem. Still, there is a theory that it could have been a scavenger dinosaur, feeding on the remains of dead animals or feeding on prey that other dinosaurs did not finish eating.

Who discovered the big lizard?

The story about the discovery of this dinosaur is really interesting. At first, you didn’t know what it really was and obviously until more remains were found there was a lot of confusion.

The Megalosaurus was called the humanum scrotum

The history of the discovery of this dinosaur goes back to 1676, in the city of Oxfordshite. Its first remains were recovered from a limestone formation in Stonesfield quarry. When Sir Thomas Pennyson found this strange fragment, he gave it to Oxford University’s Professor of Chemistry, Robert Plot.

Robert Plot published this finding with an illustration and description in the Oxfordshire Natural History in 1676. That was the first time an illustration of a dinosaur bone was published.

In the text, Robert Plot obviously did not classify it as a dinosaur (at that time it was not yet known about these extinct giants) but as a possible thigh bone of a Roman war elephant and even later it was rumored to be the bone of a giant human.

The funny thing is that Richard Brookes in 1763 named the fragment humanum scrotum, after its resemblance to a man’s testicles.

Unfortunately the bone has already been lost, but the illustration and description are detailed enough for some to identify it as that of a Megalosaurus.

Buckland’s research

At the end of the 18th century, the number of fossils in British collections began to increase very rapidly. Discoveries continued until the 19th century, when the Megalosaurus was finally described.

In 1815, the paleontologist John Kidd reports the discovery of a few giant terapod bones in the Stonesfield quarry.

A professor of geology at Oxford University, William Buckland, takes over the bones found. After studying these fossils, Buckland did not know exactly what animal the fossils belonged to.

After the Napoleonic Wars, in 1818, anatomist Georges Cuvier approached Buckland’s laboratory in Oxford and concluded that the bones were very similar to those of a giant lizard.

Buckland and his friend William Conybeare continued to investigate the bones. In 1821, they referred to the remains as a huge lizard.

In 1822, the two Oxford professors wrote a paper describing the remains. They finally concluded that they were a kind of giant lizard. Those found in the Maastricht area would end up being called Mossasaurus and for the British lizard the name Megalosaurus.

Until 1824, only the following samples were available:

  • OUM J13505: a piece of the lower right jaw with a single erupted tooth.
  • OUM J13577: a posterior dorsal vertebra
  • OUM J13579: a caudal anterior vertebra
  • OUM J13585: a cervical rib.
  • OUM J13580: a rib of the Megalosaurus
  • OUM J29881: the iliac bone of the pelvis
  • OUM J13563: a piece of pubic bone
  • OUM J13565: part of an ischium.
  • OUM J13561: bone belonging to the thigh.
  • OUM J13572: the lower part of a second metatarsal.

Obviously, he was aware that not all these samples belonged to the same skeleton. They were the remains of different Megalosaurus.

At the time Buckland classified them as lizards, and at the time he considered these animals to be crocodiles.

Curiosities about the Megalosaurus

The Megalosaurus is a somewhat controversial dinosaur of which there are several curiosities that you will find most interesting.

It was the first dinosaur that was scientifically described

As mentioned above, in 1824 the rest of what by then looked like a reptile appeared near Oxford. The British geologist William Buckland decided to do something that had never been done before, to scientifically describe the dinosaur specimen in an official document.

For a moment it was called the Humanum scrotum

In 1676, nothing was known about the existence of dinosaurs. No one knew what they were and so they were theorised as a remnant of a Roman war elephant.

A century later, a doctor named Richard Brookes copied the sketch and it occurred to him that the sample looked more like human testicles.

It has appeared in a novel by Charles Dickens

Charles Dickens was a great writer who was well known. In one of his novels, entitled “Sad House” (published in the years 1852 and 1853)

One of the paragraphs in that novel mentioned the phrase “it would be wonderful to meet a Megalosaurus, forty feet long or so, wiggling like an elephant lizard towards Holborn Hill”.

There is uncertainty about his skull

There are some parts of this dinosaur’s snout and jaws but no complete skull remains.

It’s the origin of the word dinosaur

In 1842, there were three races of “dinosaurs”. At that time they were not considered as dinosaurs but as prehistoric reptiles: Megalosaurus, Iguanodon and Hylaeosaurus.

Sir Richard Owen, upon seeing them, decided to group them into a new group called “Dinosauria”.

The main character in the series Dinosaurs is a Megalosaurus

In 1991 a new series called Dinosaurs was born. It was a comedy that revolved around the lives of dinosaurs. Earl Sinclair would be the star of this cartoon series, a megalosaur dinosaur.