Dryosaurus elderae

NPS/Bob Walters Tess Kissinger

 

Dryosaurus elderae is a species of ornithopod dinosaur from the Late Jurassic of North America, found in the Morrison Formation. Dryosaurus means “oak lizard” in reference to the leaf shaped teeth. It is a plant eating dinosaur with a beak and teeth in the back of its mouth. It had five fingers on each hand. To escape predators Dryosaurus depended on its strong legs to quickly run away.

The name elderae is for the late Ann Elder, who worked on fossils as a fossil technician and later as a museum technician at Dinosaur National Monument in the 1980s and 1990s.

 

Dryosaurus Facts

Dryosaurus is the smallest dinosaur of the Carnegie Quarry, and is related to a similar species from Tanzania, Africa.
Dryosaurus is Greek for”tree lizard”, reflective of the habitat where dryosaurus lived.
Dryosaurus size estimates range from 8-14 feet long and weighing 170-200 pounds

 

This juvenile skull is on display at the Carnegie Museum. Look closely to see an eye socket in the top left corner and teeth near the bottom left. The scale bar is 1 inch.

Both adult and juvenile Dryosaurus skeletons and skulls have been found in the Carnegie Quarry. The adult skull is the most complete best preserved in the world. Dinosaur skulls are mostly hollow and made of thin bone that often breaks. Fine sediments compress the skull during burial to flatten it the way you might step on an empty tin can. These skulls may be preserved, but some of the 3-D structure is lost. The sand-sized sediments in the Carnegie Quarry allow the Dryosaurus to be preserved in great detail without being crushed. The mounted skeleton at the Carnegie Museum of Natural History is the most complete found in Western Hemisphere and the only mounted Dryosaurus elderae in the world.

 

The adult Dryosaurus skull from Dinosaur is the best ever found. Compare the features in this cast of the adult to that of the juvenile.

The juvenile skull found is the most complete juvenile Dryosaurus skull ever found. Juvenile dinosaurs in general are rare finds. Since the bones are smaller and more fragile than those of the adults, they are easily broken or washed away in rivers before they are fossilized. Although most of the body was found, only the skull is on display.

 

Jurassic Fact

At 7.9 ft (2.4 m) Dryosaurus is the smallest adult dinosaur in the Carnegie Quarry.

 

For More Information

Visit the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania where an adult and juvenile Dryosaurus elderae from Dinosaur National Monument are on display.