Open Paleo

Spiclypeus

Mallon et al., 2016 spick-LIP-ee-us

From Latin 'spica' meaning 'spike' and 'clypeus' meaning 'shield'; meaning 'spike shield', referring to the large spike-like horn ossifications on the frill margin.

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Spiclypeus is an extinct genus of chasmosaurine ceratopsian dinosaur known from the Late Cretaceous Judith River Formation (late Campanian stage) of Montana, United States.

Diagnosis

  1. Rugose nasal contact on the lateral surface of the dorsal process of the premaxilla (autapomorphic)
  2. Postorbital horncores project dorsolaterally
  3. All six epiparietals fused at bases
  4. Epiparietals P1 and P2 curl anteriorly from posterior margin of frill
  5. Epiparietal P3 projects posterodorsally

Species

Spiclypeus shipporum Mallon et al., 2016

Type species

Named for Dr. Bill and Linda Shipp and their family, the original owners of the property in Montana on which the type specimen was discovered.

Holotype
CMN 57081 , Canadian Museum of Nature
Material
Partial skull and postcranium
Horizon
lower Coal Ridge Member, Judith River Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
8 km west-southwest of Winifred, Montana, United States

References

  1. Mallon, J. C.; Ott, C. J.; Larson, P. L.; Iuliano, E. M.; Evans, D. C. (2016). Spiclypeus shipporum gen. et sp. nov., a Boldly Audacious New Chasmosaurine Ceratopsid (Dinosauria: Ornithischia) from the Judith River Formation (Upper Cretaceous: Campanian) of Montana, USA. PLOS ONE 11(5): e0154218. Public Library of Science (PLoS). doi:10.1371/journal.pone.0154218 mallon2016a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.

    Source of the hip height estimate, and the appearance features.

    jones2026a