Nodocephalosaurus

Nodocephalosaurus is an unusual ankylosaurine known from the Late Cretaceous De-na-zin Member of the Kirtland Formation in New Mexico. Described from an incomplete cranium and partial snout, it is estimated to have measured about five metres long. What makes Nodocephalosaurus particularly intriguing is the prominent, bulbous cranial ornamentation covering its snout and forehead. These swollen, pyramid-shaped dermal projections bear a striking similarity to Asian ankylosaurines like Pinacosaurus and Tarchia, contrasting sharply with the flatter, plate-like cranial patterns seen in northern Laramidian taxa such as Ankylosaurus and Euoplocephalus. This morphology suggests complex faunal exchanges or regional endemism across North America and Asia during the Campanian. Although its postcranial skeleton is virtually unknown, it presumably wielded a robust tail club and widespread body armor.

Its bulbous, pyramid-shaped cranial ornamentation closely resembles Asian ankylosaurines rather than northern North American ones.

Where and when

Nodocephalosaurus lived in the Late Cretaceous, from 75 to 73 million years ago (Campanian age). Its remains come from United States, in the Kirtland Formation.

The numbers

Length 5 m (estimates run from 4.5 to 5.5 m). Mass about 1.9 t. Hip height about 1.4 m. That is 2.9 human-lengths, or 0.45 of a double-decker bus. These are estimates from fragmentary remains; fields marked estimated by the site are length, mass, hip height.

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