1999/03/15 by Robert M. Sullivan · 5 citations
Earth and Planetary Sciences · Environmental Science · #Paleontology and Evolutionary Biology #Evolution and Paleontology Studies #Ichthyology and Marine Biology #Skull #Paleontology #Cretaceous #Geology
paper · doi:10.1080/02724634.1999.10011128
openalex publication_date 1999/03/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
A partial skull of a new ankylosaurid dinosaur, Nodocephalosaurus kirtlandensis gen. et sp. nov., differs from known ankylosaurids in possessing a distinctive post-maxillary/lacrimal (osteoderm) ridge and a prominent quadratojugal protuberance that projects anteroventrally. Furthermore, it is distinguished by semi-inflated to bulbous, polygonal, cranial osteoderms that are bilaterally and symmetrically arranged on the frontonasal region of the skull, similar to the Asian ankylosaurids Saichania chulsanensis and Tarchia gigantea. Nodocephalosaurus kirtlandensis and these Asian genera are thus interpreted as composing a clade within the Ankylosauridae. Nodocephalosaurus kirtlandensis is from the Upper Cretaceous Kirtland Formation, De-na-zin Member, now considered to be late Campanian in age. Previously collected ankylosaurid material, from the Kirtland Formation, may pertain to this taxon rather than Euoplocephalus or Panoplosaurus, but this cannot be determined with certainty.