This week, two teams of scientists have reported finding two new horned dinosaurs in North America, one in Utah, the other in Montana. The similarity: the papers reporting the findings were both published in PLOS One.
Both dinosaurs were ceratopsians.
Machairoceratops cronusi, the specimen discovered in Utah, lived around 77 million years ago, measuring between 6 and 8 meters long, and weighing between 1 and 2 tons.
The study is based on cranial material from a single specimen, which was unearthed from the Wahweap Formation in Grand Staircase-Escalante National Monument, located in southern Utah.
This area used to be part of northern Laramidia, an ancient island continent that covered the western half of North America. The eastern half was called Appalachia. At the time, the Western Interior Seaway split the continent in two.
Study author Eric Lund told Discovery News that the dinosaur had two long, curving spikes protruding from its neck shield, or frill, each “marked by a peculiar groove extending from the base of the spike to the tip.” Lund speculated the two spikes may have helped the dinosaurs recognize others of the same species.
According to the researchers, the find is expanding scientists’ knowledge of centrosaurines from southern Laramidia. The majority of specimens are found in northern Laramidia, comprised of modern day Alaska, Alberta, Saskatchewan, and Montana.
The other new dinosaur, Spiclypeus shipporum, was described based on bones from the skull, legs, hips, and backbone. The individual specimen was found in the Judith River Formation in Montana.
“This is a spectacular new addition to the family of horned dinosaurs that roamed western North America between 85 and 66 million years ago,” said study author Jordan Mallon in a statement, who works with the Canadian Museum of Nature. “It provides new evidence of dinosaur diversity during the Late Cretaceous period from an area that is likely to yield more discoveries.”
According to researchers, the dinosaur, which they nicknamed Judith, differs from other horned dinosaurs due to the positioning of its horns over its eyes. These horns stuck out sideways from the skull. Additionally, the frill’s edges were dappled with unique spikes, some of which pointed outwards while others curled forwards.
