The Hypacrosaurus was a genus of duck-billed dinosaurs that lived in North America during the Upper Cretaceous period, between about 76.5 and 65.5 million years ago. It was one of the last surviving members of the lambeosaurine hadrosaurid. There are two known species; Hypacrosaurus altispinus and Hypacrosaurus stebingeri. These two species are not differentiated by typical characteristics but rather described based on their evolution from the Lambeosaurus

Key facts

Hypacrosaurus pronunciationHi-pak-roh-sore-us
What does Hypacrosaurus mean?Near-topmost lizard
Dinosaur typeOrnithopod
On the menuHerbivorous
Length9 meters ( 30 feet)
Height3.5 m (11 feet 5 inches )
Weight3500 kg (about 7700 lbs)
Life expectancyUnknown
Legs used to get aroundBipedal/Quadruped
Estimated top speedUnknown
When they livedUpper Cretaceous era 70 million years ago
Where they have been found?Canada, USA

When & Where

The first Hypacrosaurus fossils were collected in 1910 by American paleontologist Barnum Brown. The fossils, consisting of an incomplete postcranial skeleton and pelvis, were discovered along the Red Deer River close to Tolman Ferry in Alberta, Canada. Brown enlisted these remains as a new genus in 1913 in combination with other postcranial skulls. He named the genus Saurolophus. 

Since then, many more fossils have been found, providing scientists with a better understanding of this fascinating creature. 

Size & Weight

The Hypacrosaurus was a large creature, measuring up to 30 feet long and weighing up to 4 tons. It had a long neck and tail and was covered in scaly skin. The neural spines that projected from the vertebrae were 5 to 7 times the body’s total height, thereby depicting it as having a tall back. 

Mobility & Diet

The Hypacrosaurus is pictured to have been both bipedal and quadrupedal. As a hadrosaur, it is also believed to have been a herbivorous dinosaur. This is for several reasons, such as the flexibility of their skulls to facilitate grinding motion, the cheek-like organ that helped hold food material in the jaws, and the hundreds of teeth that were grouped into dental batteries.   

Interesting Points

  • Hypacrosaurus was a member of duckbill dinosaurs that lived in large herds in present-day North America and Canada.
  • Hypacrosaurus is the most recognizable dinosaur from other hollow-crested duckbills because of its tall neural spines and unique crest.
  • A specimen from the Royal Tyrrell Museum was seen in the 1998 IMAX Film T-Rex: Back to the Cretaceous.
  • In March 2020, scientists obtained DNA and proteins from a Hypacrosaurus fossil, making it the oldest dinosaur DNA ever found. The research was published in the journal Nature Communications.

Featured Image Credit: Nobu Tamura, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons