Open Paleo

Tatankacephalus

Parsons & Parsons, 2009

From Oglala Lakota tatanka ('bison') and Greek kephale ('head'), meaning 'bison head', in reference to the rounded head form

113.2–100.5 million years ago Albian, Early Cretaceous
Early Cretaceous stages

Tatankacephalus is a basal genus of nodosaurid dinosaur that lived during the Early Cretaceous. Its length has been estimated at 7 meters (23 ft).

Diagnosis

  1. Unsegmented, enlarged nuchal ridge
  2. Concave lateral process projecting from paroccipital process
  3. Keeled osteoderm on jugal process of quadratojugal dorsal to quadratojugal boss
  4. Frontoparietal dome with convex lateral profile
  5. Circular orbit
  6. Posteroventrally directed foramen magnum opening

Species

Tatankacephalus cooneyorum Parsons & Parsons, 2009

Type species

Named for the family of John Patrick Cooney, honoring their contributions in connection with the fossil.

Holotype
MOR 1073 , Museum of the Rockies
Material
Partial cranium consisting of fragmentary nasal region with internasal septum, premaxillary fragments with three alveoli, maxillary-nasal fragment, orbital-postorbital-quadratojugal fragment, isolated tooth, posterior cranial fragment including parietal, squamosal, occiput, quadrate, braincase, postorbital, orbit, pterygoids, basisphenoid, basioccipital, parasphenoidal rostrum. Rib fragments and osteoderms may belong to same individual.
Horizon
Himes Member, Cloverly Formation, Albian, Early Cretaceous , 113.2–100.5 million years ago
Locality
Middle Dome region, Montana, United States

References

  1. Parsons, W. L.; Parsons, K. M. (2009). A new ankylosaur (Dinosauria: Ankylosauria) from the Lower Cretaceous Cloverly Formation of central Montana. Canadian Journal of Earth Sciences 46: 721-738. doi:10.1139/E09-045 parsons2009a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Source of the mass and hip height estimates, and the appearance features.

    jones2026a