The Eoraptor was a small, hollow-boned Triassic dinosaur that lived about 228 million years ago. The Eoraptor was one of the first dinosaurs, but it wasn’t discovered until 1991. An Eoraptor was quick, running up to 35 miles per hour to chase prey. That’s as fast as a rabbit!
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Some Quick Facts about the Eoraptor
| Name | Eoraptor (meaning “dawn plunderer” or “dawn thief”) |
| Type of dinosaur | early Saurischian (Saurischia) |
| Territory | Floodplain area covered by forests with giant ferns and conifer trees, Argentina, South America |
| Size | 3-5.5 feet long, 19-20 inches long |
| Color | Grayish |
| Interesting Characteristics | Hollow bones made them lightweight. They had long, thin hind legs, and hands on their forelimbs with three clawed fingers and two smaller fingers |
| Diet | Smaller dinos, fish, birds, leaves, and plant material |
| Major Threats | Natural disasters and larger predators |
The Eoraptor was an early dinosaur found by paleontologist Ricardo Martínez. The primitive dinosaur skeleton was found in the Ischigualasto Formation in Northwestern Argentina. Because of their features, paleontologists have debated whether Eoraptor was a true dino or an archosaur.
While the Eoraptor is currently considered part of Dinosauria, this early dinosaur has been reclassified since it was first discovered in 1991.
What Kind of Dino is the Eoraptor?
When the Eoraptor was discovered in 1991, it was considered the earliest known dinosaur and a theropod. The debate continued among paleontologists, but it wasn’t until the remains of a new dinosaur were discovered in 2011 that the Eoraptor’s classification was changed to a basal (early) sauropod.
The new dinosaur that changed everything for the Eoraptor was a small Triassic dinosaur named Eodramaeus. This dino lived 230 million years ago, making it older than the Eoraptor. The Eodrameaus (Latin for “dawn runner”) is now considered the earliest known dinosaur and the first theropod.
What Does the Eoraptor’s Name Mean?
The full scientific name of the Eoraptor is Eoraptor lunensis. Eoraptor lunensis means “dawn plunderer from the Valley of the Moon.” The name Eoraptor lunensis is a reference to the significant ties it has to the place where it was found in Argentina
In 1993, the Eoraptor was described and named by Paul Sereno, Catherine Forster, Alfredo M. Monetta, and Raymond R. Rogers. They chose the name Eoraptor in reference to it being an early dinosaur (“eo” from the Greek word for dawn, “raptor” in reference to its body type). The name lunensis is from the Latin for “moon” (luna) and “inhabitant” (ensis).
The place where the Eoraptor was discovered is called Valle de la Luna (Valley of the Moon). Even though it was once a wetland full of lush greenery, today, it looks more like the moon’s surface. 228 million years later, the Eoraptor wouldn’t recognize the place it once called home.
How Many Species of Eoraptor Are There?
The Eoraptor lunensis is the only species of Eoraptor. Many primitive dinosaur skeletons found in Argentina are believed to be juveniles. The fossil evidence found so far includes three skeletons.
The Eoraptor wasn’t the only early dinosaur found in Argentina’s Ischigualasto Formation. Eoraptor was discovered next to Herrerasaurus and Panphagia. Both Herrerasaurus and Panphagia were Late Triassic dinosaurs that lived around the same time as Eoraptor.
What Does an Eoraptor Eat?
The Eoraptor was once considered a carnivore, but closer inspection of its teeth showed that it was an omnivore with herbivore tendencies. The hot and humid floodplains of Argentina that the Eoraptor called home were full of plant life, which an Eoraptor crushed with its leaf-shaped teeth. At other times, this quick sprinter could catch smaller dinos and reptiles, grabbing them with clawed hands.
Using the sharp teeth in its upper jaw, the Eoraptor quickly tore apart its prey. But an Eoraptor could only eat small prey because this early dinosaur couldn’t open its mouth wide enough for bigger pieces of meat. Later carnivores and omnivores had a sliding joint in the lower jaw to eat larger prey.
Are Eoraptors Related to Velociraptors?
The short answer is no. Velociraptors are part of the dromaeosaurids genus, which means they are a type of theropod. Eoraptors are sauropods. Eoraptors are also much smaller than later raptors. While they are both dinosaurs, Eoraptors and Velociraptors are not related.
Paleontologists called Eoraptor a raptor in 1993 because they assumed it was a carnivore. The grasping hands and overall appearance also played a part in the Eoraptor.
In the world of paleontology, the Eoraptor is a new dinosaur discovery. Many dinos we know and love today were found more than a century before the Eoraptor. Because we are still learning more about this awesome dino, there’s still a lot of debate about the Eoraptor and how it is classified. For now, the Eoraptor is considered a basal sauropodomorph and remains one of the earliest known dinosaurs.