title: A new ankylosaurid dinosaur from the Upper Cretaceous (Kirtlandian) of New Mexico with implications for ankylosaurid diversity in the Upper Cretaceous of western North America.
abstract: A new ankylosaurid (Ankylosauria: Dinosauria), Ziapelta sanjuanensis, gen. et sp. nov., is based on a complete skull, an incomplete first cervical half ring, a possible fragment of the second cervical half ring, and additional fragmentary osteoderms. The holotype specimen is from the Upper Cretaceous (Upper Campanian, Kirtlandian Land-Vertebrate Age) Kirtland Formation (De-na-zin Member) at Hunter Wash, San Juan Basin, in northwestern New Mexico, USA. Diagnostic characters of Ziapelta include: a large, prominent triangular median nasal caputegulum; a mixture of flat and bulbous frontonasal caputegulae; ventrolaterally oriented squamosal horns with a sharp, prominent dorsal keel; and the ventral surface of basicranium with three prominent anteroposteriorly oriented fossae. A phylogenetic analysis suggests that Ziapelta is not closely related to the other ankylosaurid from the De-na-zin Member, Nodocephalosaurus, but allies it to the northern North American ankylosaurids Ankylosaurus, Anodontosaurus, Euoplocephalus, Dyoplosaurus, and Scolosaurus.
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Victoria M
authors.initials: VM
authors.lastname: Arbour
authors.affiliation: Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Burns
authors.affiliation: New Mexico Museum of Natural History and Science, Albuquerque, New Mexico, United States of America.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Sullivan
authors.affiliation: New Mexico Museum of Natural History and Science, Albuquerque, New Mexico, United States of America.
authors.forename: Spencer G
authors.initials: SG
authors.lastname: Lucas
authors.affiliation: New Mexico Museum of Natural History and Science, Albuquerque, New Mexico, United States of America.
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Cantrell
authors.affiliation: Department of Geosciences, Fort Hays State University, Hays, Kansas, United States of America.
authors.forename: Joshua
authors.initials: J
authors.lastname: Fry
authors.affiliation: New Mexico Museum of Natural History and Science, Albuquerque, New Mexico, United States of America.
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Suazo
mesh_terms: D000818:Animals; D025061:Dinosaurs; D005580:Fossils; D009516:New Mexico; D009656:North America; D010802:Phylogeny; D013045:Species Specificity