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Dinosaur: Agathaumas sylvestris
Cretaceous: 72.1–66 Ma

Length*: | 6.2 m | 20.3 ft |
Weight*: | 3.5 t | 7,716 lb |
*The largest known specimen
Period
Epoch: Late Cretaceous
Stage: Late Maastrichtian
Years: 72.1–66 Ma
Details
Status: nomen dubium
Author: Cope
Year: 1872
Distribution
Area: North America
Country: USA
Region: Wyoming
Formation: Lance
Sources
Material: 16 vertebrae (dorsal, sacral, caudal), partial pelvis and several ribs.
References: Cope, E.D. (1872). "On the existence of Dinosauria in the Transition Beds of Wyoming."
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