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014

Eoraptor lunensis

OLogy Series
extinct animal
card
014

Eoraptor lunensis

OLogy Series
extinct animal

In the early 1990s, paleontologists found Eoraptor lunensis, one of the oldest known dinosaurs (tied with Herrerasaurus and Pisanosaurus). It lived 228 million years ago in Argentina. However, new dinosaur finds in Madagascar may be even older. Stay tuned...

In 1993, paleontologist Paul Sereno and his team found a 228 million-year-old skeleton. He named it Eoraptor ("dawn plunderer"). Based on the age of the rocks in which he found it, he realized it lived at the beginning of the Age of Dinosaurs. It did have some "advanced" dinosaur features, such as hollow bones and small fourth and fifth fingers. This shows that although it was a very early dinosaur, there must have been other dinosaurs before it.

Eoraptor's skull is about the size of:

a watermelon

a grape

an orange

Are you right?

Correct!

Eoraptor's skull is relatively small. Some theropod skulls, such as T. rex can be longer than 1.2 meters (4 feet)!

Paul Sereno
paleontologist

Eoraptor may be as close as we'll get for some time to the ultimate ancestor of dinosaurs.

Eoraptor was found recently in a desert. But 228 million years ago, this area was filled with lakes and lush green plants.

Fact
or
Fiction
?

Fact

The rocks that the Eoraptor fossil was found in show evidence that the area was wetter during the Triassic Period.

Scientific Name: Eoraptor lunensis
Pronunciation: EE-oh-rap-ter loo-NEN-sis
Meaning: "dawn plunderer"
Locality Found: Argentina, South America
Age: Middle Triassic, 228 million years ago
Length: 1 meter (3 feet) long
Weight: 3.5 kilograms (8 pounds)
Characteristics: This small therapod is one of the oldest known dinosaurs. It had sharp teeth and was probably a fast runner.

Image credits: Rick Spears; Paul Sereno: courtesy Paul Sereno.