Deinosuchus
Deinosuchus hatcheri

Deinosuchus was probably the biggest crocodilian that ever lived
Advertisement
Deinosuchus Scientific Classification
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Reptilia
- Order
- Crocodilia
- Family
- Alligatoroidea
- Genus
- Deinosuchus
- Scientific Name
- Deinosuchus hatcheri
Read our Complete Guide to Classification of Animals.
Deinosuchus Conservation Status
Deinosuchus Facts
- Most Distinctive Feature
- Deinosuchus had a broad and enlongated skulll
- Habitat
- Both sides of the North American Western Interior Seaway.
- Diet
- Carnivore
Deinosuchus Physical Characteristics
- Weight
- 5511.6-30864.7 lbs
- Length
- 26-33 ft
- Venomous
- No
- Aggression
- High
View all of the Deinosuchus images!
Deinosuchus is an extinct crocodyliform that was closely related to crocodiles and alligators. This extinct reptile lived during the Cretaceous era 82-73 million years ago. It lived alongside many giant animals, including dinosaurs, giant sharks, and marine reptiles like mosasaurs. This 33-foot-long alligator lived in North America and was one of the most formidable carnivores of its time, even though it shared a habitat with some of the largest animals known to man.
Description and Size
Deinosuchus is a Greek word formed from two words, “deinos,” and “soukhos,” meaning “terrible crocodile.” The name is a reference to this reptile’s massive size and ferocious appearance, which would have made it quite fearsome. Deinosuchus was a very large crocodyliform. It had a set of strong teeth built for crushing prey, and its back was lined with massive hemispherical osteoderms.
Deinosuchus was similar to caimans and alligators in many ways. Its head was shaped like theirs, with a broad and elongated skull. Estimating the Deinosuchus‘ size was a little difficult for scientists because of the fragmented nature of the fossils. Based on reasonably accurate reconstructions, paleontologists think the Deinosuchus would have been about 26-33 feet long on average and might have weighed between 2.5-14 tons. Their average size varied from one species to the other, and the largest specimen ever found reached lengths of about 39 feet.
Based on the possible maximum size estimate of the Deinosuchus, it was probably the biggest crocodilian that ever lived and also the largest carnivorous archosaur. Deinosuchus had up to 30 massive teeth. The teeth were strong and thick, with each one about 2.8 inches long. Instead of piercing prey like many carnivores, the shape and form of the teeth show that they were made for crushing.

had up to 30 massive teeth each roughly 2.8 inches in length used for crushing its prey.
Diet — What Did Deinosuchus Eat?
Deinosuchus was carnivorous and one of the largest predators of its time, with few competitors. Based on the tremendous bite strength of this crocodilian, some experts speculate that it might have preyed on dinosaurs. However, Deinosuchus would have hunted most of its prey in the water since claims that it spent a lot of time on the ground like modern crocodiles are unconfirmed. They fed predominantly on fish, sea turtles, and other marine reptiles. There’s also a chance to attack terrestrial prey by ambushing them at the water’s edge.
Habitat — When and Where It Lived
Deinosuchus lived during the late Cretaceous period. Fossils of this crocodilian have been found on both sides of the North American Western Interior Seaway— an ancient inland seaway that divided the continent into two land masses. Deinosuchus lived in this area between 82 to 73 million years ago.
Many paleontologists think it was a semi-aquatic animal that could walk on land but spent most of its time in the water. The fossil distribution suggests that this giant crocodilian preferred estuarine habitats.
Like many modern crocodiles, Deinosuchus had a secondary bony palate. Crocodilians with this feature can breathe by raising their nostrils above the water surface while the rest of their head and body remain submerged. However, experts often point to the massive osteoderms on the Deinosuchus as evidence that they were well-adapted to living on land since the tissues connected to the osteoderms had significant load-bearing capacity.

Paleontologists believe the
Deinosuchuswould have been about 26-33 feet long on average and weighed between 2.5-14 tons.
Threats and Predators
Deinosuchus was a large and terrifying predator that ruled the Western Inland Seaways during the Cretaceous period. Experts think it was one of the largest crocodilians that ever walked the planet. It lived alongside many giant dinosaurs and mosasaurs. None of these animals would have been big enough to prey on an adult Deinosuchus. However, they did compete for the same food sources since they shared a habitat. Also, young Deinosuchus probably fell prey to larger marine reptiles.
Discoveries and Fossils — Where It Was Found
Deinosuchus was first discovered in 1858 when the geologist Ebenezer Emmons found two large teeth fossils in Bladen County, North America. The teeth fossils were misidentified as belonging to Polyptychodon, a type of pliosaur. Later in 1903, paleontologists found fossil osteoderms which they initially assigned to the Euoplocephalus, a variety of armored dinosaurs. However, the discovery of more osteoderms, vertebrae, ribs, and pubis bones showed that the initial find was a large crocodilian and not a dinosaur.
In 1909, W.J. Holland described and named the first species of the Deinosuchus genus, Deinosuchus hatcheri. In 1940 and beyond, more Deinosuchus fossils were unearthed, and more research was done to get a complete picture of this reptilian’s appearance and behavior.

A
Deinosuchusjaw fragment fossilized.
Extinction — When Did Deinosuchus Die Out?
Deinosuchus went extinct towards the end of the Cretaceous Period about 73 million years ago. The exact reason for their extinction isn’t known. However, many experts agree that the disappearance of this species occurred before the main extinction event that occurred at the end of the period. The extinction event which took place 66 million years ago wiped out the rest of the non-avian dinosaurs still living at the time.
Similar Animals to the Deinosuchus
Other animals similar to Deinosuchus include:
- Sarcosuchus: This is an extinct crocodilian that lived during the early Cretaceous. They lived in Africa and South America and might have reached lengths of up to 30 feet.
- Stomatosuchus: Stomatosuchus is a group of extinct crocodyliforms that lived in Africa during the Late Cretaceous. Unlike other crocodilians, the Stomatosuchus had a toothless mandible that gave it a bizarre appearance.
- Mosasaurus: This group of massive marine reptiles lived during the Late Cretaceous alongside other giant marine reptiles like Deinosuchus.
Related Animals
- Machimosaurus rex
- Mosasaurus
- Elasmosaurus
Deinosuchus FAQs (Frequently Asked Questions)
When was the Deinosuchus alive?
Deinosuchus was alive from 82 to 73 million years ago during the Cretaceous period. The Cretaceous period was the last in the Mesozoic era and was the longest period ever. They might have died shortly before the mass extinction at the end of the Mesozoic period.
How big was Deinosuchus?
Deinosuchus adults were about 26-33 feet long on average and might have weighed between 2.5-14 tons. They were among the largest crocodilians to have ever lived.
Was Deinosuchus an alligator or a crocodile?
Deinosuchus were considered crocodilian. This group includes the modern crocodiles, alligators, and gharials. However, the Deinosuchus genus was more closely related to modern alligators than crocodiles.
Thank you for reading! Have some feedback for us?
Contact the AZ Animals editorial team
Thank you for your feedback!
We appreciate your help in improving our content.
Our editorial team will review your suggestions and make any necessary updates.
There was an error submitting your feedback. Please try again.
Sources
- Western Australian Museum / Accessed October 31, 2022
- Wikipedia / Accessed October 31, 2022
- Dinopedia / Accessed October 31, 2022