Panoplosaurus
From Greek 'panoplos' meaning 'fully armored' or 'well-armored' and '-saurus' meaning 'lizard', referring to its extensive armor plating.
Panoplosaurus is a genus of armored dinosaur from the Late Cretaceous of Alberta, Canada. Few specimens of the genus are known, all from the middle Campanian of the Dinosaur Park Formation, roughly 76 to 75 million years ago. It was first discovered in 1917, and named in 1919 by Lawrence Lambe, named for its extensive armor, meaning "well-armored lizard". Panoplosaurus has at times been considered the proper name for material otherwise referred to as Edmontonia, complicating its phylogenetic and ecological interpretations, at one point being considered to have existed across Alberta, New Mexico and Texas, with specimens in institutions from Canada and the United States. The skull and skeleton of Panoplosaurus are similar to its relatives, but have a few significant differences, such as the lumpy form of the skull osteoderms, a completely fused shoulder blade, and regularly shaped plates on its neck and body lacking prominent spines. It was a quadrupedal animal, roughly 5 m (16 ft) long and 1,600 kg (3,500 lb) in weight. The skull has a short snout, with a very domed surface, and bony plates directly covering the cheek. The neck had circular groups of plates arranged around the top surface, both the forelimb and hindlimb were about the same length, and the hand may have only included three fingers. Almost the entire surface of the body was covered in plates, osteoderms and scutes of varying sizes, ranging from large elements along the skull and neck, to smaller, round bones underneath the chin and body, to small ossicles that filled in the spaces between other, larger osteoderms.
Diagnosis
- Vomers laterally swollen, enclosing a hollow median canal in mature individuals or a deep ventral groove in juveniles
- Median narial caputegulum with a laterally extending wedge separating the nares (or supranarial caputegulae) from the nasal caputegulae
- Four or five nasal caputegulae in two paired rows forming transverse bands across the muzzle (five when the internasal caputegulum is present)
- Lacrimal caputegulae small, contacting the nasal caputegulae medially and not extending over the dorsal skull surface
- Postorbital boss covered by numerous small, randomly arranged caputegulae
- Basal tubera anterolaterally oriented, separated by a shallow median depression on the ventral surface of the basioccipital
Species
Panoplosaurus mirus Lambe, 1919
Type species
From Latin 'mirus' meaning 'wonderful' or 'remarkable'.
- Holotype
- CMN 2759 , Canadian Museum of Nature
- Material
- Practically complete skull with teeth; ~3 ft of articulated vertebrae (atlas to thoracics) with ribs; humerus, ulna, radius and three fore-foot digits; partial scapulocoracoid, sternal bone, ilium fragment, part of sacrum, hind-foot elements; and ~200 scutes and ossicles
- Horizon
- lower Dinosaur Park Formation, Campanian, Late Cretaceous , 83.6–72.2 million years ago
- Locality
- Quarry 008, 4.4 km south of the mouth of Little Sandhill Creek, Alberta, Canada
References
- Lambe, L. M. (1919). Description of a new genus and species (Panoplosaurus mirus) of an armoured dinosaur from the Belly River Beds of Alberta. Proceedings and Transactions of the Royal Society of Canada, series 3 13: 39-50. lambe1919a
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Livius, M. C. H.; Witmer, L. M.; Ryan, M. J.; Maddin, H. C.; Mallon, J. C. (2026). Redescription of the Panoplosaurus mirus (Ankylosauria: Nodosauridae) holotype skull using computed tomography, and a new comparative scheme for panoplosaurin cranial ornamentation. Journal of Vertebrate Paleontology. doi:10.1080/02724634.2026.2636589
CT redescription of the Panoplosaurus mirus holotype skull (CMN 2759); source of the amended cranial diagnosis.
livius2026a -
Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Ornithischians. Princeton University Press.
Source of the hip height estimate, and the appearance features.
jones2026a