Eobrontosaurus is a dinosaur is known to be originated from the Jurassic of North America with its name holding a meaning ‘dawn thunder lizard’, The animal is a saurapod having similar characteristics of Apatosaurus, They have an origin estimated to be 154 million years ago in the region of Morrison Formation with 21 meters of length which is 69 ft.


Their generic name has its origin from the Lakota mah-koo yah-nah-pin referred to as the ‘breast necklace’ since their sterna ribs are a look alike of hair pipes which are worn by the people of the tribe historically. Another similar species type E.yahnahpin explained with the help of James Filla and Patrick Redman was known to be the specimen coming under the Apatosaurus(A.yahnahpin) in the year of 1994. The unique holotype is a postcranial skeleton known to be TATE-001 having its origin in Morrison Formation the place of Wyoming. Many other samples of the specimen have been declared to be found.

Another research in the year of 1998 by Robert T. Bakker proposed the new specific name to be Eobrontosaurus having its origin from Greek Goddess of the dawn and the name Brontosaurus known to be from the specific name of Apatosaurus excelsus, There were many questions that Eobrontosaurus yahnahpin’s root is on Camarasaurus only but Bakker postulated that Eoborontosaurus comes under Diplodocidae which is nothing but Apatosaurine.

Eobrontosaurus facts:
Name: Eobrontosaurus (Dawn thunder lizard).
Named By:

Robert T. Bakker - 1998.

Time period:

Kimmeridgian to Tithonian of the Jurassic.

Fossil representation: Almost complete post cranial skeleton as well as additional fragmentary remains.