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Dinosaur: Sphaerotholus lyonsi
| Length*: | 1.95 m | 6.4 ft |
| Weight*: | 28 kg | 62 lb |
*The largest known specimen
Period
Epoch: Late Cretaceous
Stage: Late Maastrichtian
Years: 72.1–66 Ma
Details
Distribution
Area: North America
Country: USA
Region: Montana
Formation: Hell Creek
Locations
Sources
Material: Nearly complete right squamosal.
References: Woodruff, D. Cary; Schott, Ryan K.; Evans, David C. (2023). "Two new species of small‐bodied pachycephalosaurine (Dinosauria, Marginocephalia) from the uppermost Cretaceous of North America suggest hidden diversity in well‐sampled formations".
