Fun Marshosaurus Facts For Kids

Arpitha Rajendra
Oct 20, 2022 By Arpitha Rajendra
Originally Published on Sep 29, 2021
Edited by Jacob Fitzbright
Fact-checked by Kidadl Team
Read more amazing Marshosaurus facts here.
Age: 3-18
Read time: 5.8 Min

Marshosaurus is a genus consisting of medium-sized carnivorous dinosaurs of the family Piatnitzkysauridae and the superfamily or clade Megalosauroidea. This predator theropod measures around 15 feet (4.5 meters). They lived in the Late Jurassic Morrison Formation of Utah and probably of Colorado. There were theropod fossils found with thousands of fossil bones in the 1960s. Madsen, in 1976 named one of these fossils as Marshosaurus bicentesimus, the type species. The common name was given to honor the famous Professor Othniel Charles Marsh, a nineteenth-century paleontologist who described a lot of fossils of dinosaurs during the Bone Wars. The specific scientific term was given 'in honor of the bicentennial of the United States of America'. The UMNH VP 6373 holotype was recovered from a Brushy Basin Member's layer of the Morrison Formation from the Late Kimmeridgian around 155-152 million years ago. There are three genera described within this family of Piatnitzkysauridae. This family name was given based on the genus Piatnitzkysaurus, which is well-known and most complete. So, Piatnitzkysauridae is also more closely related to Piatnitzkysaurus than Megalosaurus or Spinosaurus.

If you enjoyed these fun facts about these Marshosaurus dinosaurs, then you may check out some amazing facts about the Metriorhynchus and Chilantaisaurus on Kidadl.

Marshosaurus Interesting Facts

How do you pronounce 'Marshosaurus'?

The pronunciation of Marshosaurus is 'marsh-o-sore-us.'

What type of dinosaur was a Marshosaurus?

Marshosaurus bicentesimus (Madsen, 1976) is a medium-sized predator classified within the clade Theropoda in Saurischia. Major fossil bones collected from Cleveland-Lloyd Quarry, central Utah in the 1960s were of Allosaurus, including at least two fossils, one of the small Stokesosaurus dinosaur and another of Marshosaurus bones. Later analysis of Marshosaurus dinosaur showed that this dinosaur group was a member of Avetheropoda (bird-like theropods) like Velociraptor, Allosaurs, and Tyrannosaurus. However, a phylogenetic analysis was done by Roger Benson that showed this was a megalosaurid.

In which geological period did the Marshosaurus roam the Earth?

Marshosaurus bicentesimus (Madsen, 1976) was from the Late Jurassic time period (around 155-152 million years ago) of the Morrison Formation of Utah and probably Colorado.

When did the Marshosaurus become extinct?

Marshosaurus bicentesimus (Madsen, 1976) of the Late Jurassic period probably became extinct during the Cretaceous-Paleogene time period around 66 million years.

Where did a Marshosaurus live?

These theropod dinosaur species of the Late Jurassic lived across a range in North America. These dinosaur species were found Cleveland-Lloyd Quarry, central Utah, it was one fossil among the many Allosaur fossils. In the layer of Brushy Basin Member, Morrison Formation UMNH VP 6373 holotype was recovered. The Marshosaurus vertebrae of the tail and CMNH 21704 (Dinosaur National Monument) were also recovered. You can find a reconstructed skull (based on referred material) of these Jurassic dinosaurs in the Carnegie Natural History Museum, Pennsylvania.

What was a Marshosaurus's habitat?

These theropod dinosaurs of Utah preferred terrestrial habitats. The Morison Formation consisted of a sequence of alluvial and shallow marine sediments that ranges from 156.3 million years ago at the bottom and 146.8 million years ago at the top. This formation is defined as a semi-arid habitat with dry and wet seasons. The range of this Morison-Basin stretched from New Mexico through Saskatchewan and Alberta. The rivers and streams carried the deposits from the east-facing drainage basins that got deposited in lakes, swampy lowlands, floodplains, and river channels. This formation became the center of the Bone Wars in 1877.

Who did a Marshosaurus live with?

These theropod predators of Utah may have lived in groups like other dinosaurs and might have also hunted together.

How long did a Marshosaurus live?

The exact lifespan of these dinosaurs is not known.

How did they reproduce?

The reproduction of these predatory dinosaurs of the Late Jurassic was oviparous, similar to other dinosaurs. There was no information available on the research of breeding, incubation, or parental care given by these species.

Marshosaurus Fun Facts

What did a Marshosaurus look like?

Marshosaurus bicentesimus dinosaurs have amazing fun facts for kids and adults.

Marshosaurus (Utah) was a medium-sized theropod species. Matthew Carrano in 2012 established one autapomorphy that is a suture between the pubic bone and pubic peduncle is concave at the rear and convex that curves upwards at the front. Dinosaur National Monument's CMNH 21704, a partial skeleton, was referred to because the dorsal neural spines were identical to the ones found in Cleveland-Lloyd Quarry. Marshosaurus bicentesimus' one right ilium was deformed, which was believed to be due to an injury. Another fossil has a pathological rib.

How many bones did a Marshosaurus have?

It is not known how many bones were there in the Marshosaurus skeleton. Few of the Marshosaurus skeletal remains were the skull, left ilium, pubic bone, ischia, six jaw fragments, and three ilia.

How did they communicate?

The mode of communication of these predator dinosaurs of the Late Jurassic is not known. They may have communicated through body language, calls, and songs.

How big was a Marshosaurus?

Marshosaurus size is around 15 ft (4.5 m) long, estimated by Gregory S. Paul. The size of the ilium holotype was 14.8 in (37.5 cm) and the skull measured up to 24 in (60 cm). Also, the Marshosaurus length is less than half of Torvosaurus, which measures up to 39 ft (12 m). Allosaurus' length is almost twice the size of the Marshosaurus.

How fast could a Marshosaurus move?

There is no information on research done on the running speed of these dinosaurs of Theropoda. Like other bipedal dinosaurs, these species may have been pretty fast.

How much did a Marshosaurus weigh?

Marshosaurus weight range was around 440 lb (200 kg).

What were the male and female names of the species?

There is no specific name given to either male or female Marshosaurus of Utah.

What would you call a baby Marshosaurus?

There is no specific name given to baby Marshosaurus of the Jurassic Age.

What did they eat?

These species of Utah were carnivores and hunted small dinosaurs. In the natural history museum, Utah, a display shows that the Marshosaurus considers a dead Stegosaurus snack.

How aggressive were they?

The information about the level of aggressiveness of these carnivorous theropods is not available.

Did you know...

Bone wars occurred due to a rivalry that was caused by the collection of fossils between Edward Drinker Cope and Othniel Charles Marsh, early paleontologists.

Another dinosaur named after the famous paleontologist Othniel Charles Marsh is Othnielsaurus in 2007.

The Morrison Formation had huge sauropods like Diplodocus, Apatosaurus, and Barosaurus. Few dinosaurs that lived with Marshosaurus were species like Stegosaurus and Dryosaurus and some predators were Torvosaurus, Allosaurus, and Ceratosaurus that occupied at the top of the food chain in the Morrison formation region.

There are two shortcuts within Torvosaurus, Torvosaurus gurneyi, and Torvosaurus ingens. The type species name Torvosaurus tanneri.

Allosaurus translates to 'different lizard,' which is a combination of the Greek allos meaning 'different other' and saurus means 'lizard.' A specimen of this genus named Bug Al is a 95% complete fossil remains of this species discovered in 1991.

Who discovered Marshosaurus?

It is not clearly known who first discovered Marshosaurus in Utah.

What do we know about the Marshosaurus?

Marshosaurus is a medium-sized theropod of the Late Jurassic that occupied North America. This dinosaur is bipedal with short arms. These species had a large skull and were excellent hinters. They also preferred semi-arid environments.

Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! For more relatable content, check out these Puertasaurus facts and Tupuxuara facts for kids.

You can even occupy yourself at home by coloring in one of our free printable Marshosaurus coloring pages.

Marshosaurus Facts

What Did They Prey On?

Small dinosaurs

what Type of Animal were they?


Average Litter Size?


What Did They Look Like?


How Much Did They Weigh?

440 lb (200 kg)

Skin Type


How Long Were They?

15 ft (4.5 m)

How Tall Were They?










Scientific Name

Marshosaurus bicentesimus

What Were Their Main Threats?

Natural disasters

What Habitat Did They Live In?

Terrestrial and semi-arid habitats

Where Did They Live?

North America
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Written by Arpitha Rajendra

Bachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

Arpitha Rajendra picture

Arpitha RajendraBachelor of Engineering specializing in Aeronautical/Aerospace Technology, Master of Business Administration specializing in Management

With a background in Aeronautical Engineering and practical experience in various technical areas, Arpitha is a valuable member of the Kidadl content writing team. She did her Bachelor's degree in Engineering, specializing in Aeronautical Engineering, at Nitte Meenakshi Institute of Technology in 2020. Arpitha has honed her skills through her work with leading companies in Bangalore, where she contributed to several noteworthy projects, including the development of high-performance aircraft using morphing technology and the analysis of crack propagation using Abaqus XFEM.

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