New ‘Sword-Horned’ Dinosaur Unearthed in Utah

With its fierce face, prickling with unusual curved horns, a new dinosaur found in southern Utah has been named after a fearsome eponym: Cronus, the Greek god who castrated his father with a scythe.

But names aside, the newly discovered species of ceratops is offering scientists rare new insights into a group of dinosaurs whose remains are rarely found in the Southwest.

Paleontologists believe it’s an early form of centrosaurine, a type of ceratopsid typified by a short skull, a big nose, and a small but often lavish frill around the back of its head.

The fossil consists of most of the animal’s skull, originally discovered in 2006 in a layer of mudstone in Utah’s Grand Staircase Escalante National Monument, not far from the Arizona border.

utah ceratopsid dinosaur fossil
The fossil material and a cranial reconstruction of Machairoceratops. (Image courtesy Lund et al.)
[See what else has been found in Grand Staircase lately: “New Tyrannosaur Species, ‘King of Gore,’ Reveals Origins of T. Rex“]

And the skull fragments mostly fit the description of a centrosaurine, said Eric Lund, a researcher at Ohio University’s paleontology lab.

But the specimen took the dinosaurs’ frill ornaments to new lengths.

In part because of its large, curved, fluted horns, it was deemed both a new genus and species, named Machairoceratops cronusi — “machairo” after the Greek word for “bent sword,” and “cronus” for the deity who neutered his more powerful father, Uranus.

Machairoceratops is unique in possessing two large, forward-curving spikes off of the back of the neck shield, each of which is marked by a peculiar sulcus, or channel, extending from the base of the spike to the tip, the function of which is currently unknown,” Lund said in a press statement.

The horns — in addition to reminding people of Cronus’ weapon of choice — appear to be unique on such a ceratopsid, Lund and his colleagues report.

But Machairoceratops also has many features in common with one of its contemporaries — the flamboyant Diabloceratops, another centrosaurine whose sole specimen has been found in Grand Staircase Escalante.

“The new specimen shares several morphologic features with Diabloceratops,” Lund and his colleagues write, in the online journal PLOS One, “including robust, elongate supraorbital ornamentation, a triangular (rather than round) … frill, and elongate spike-like … ornamentation.”

At once similar but clearly distinct, the specimen was deemed “the definitive sister taxon” to Diabloceratops.

And, given that it was found in sediments dated to 77 million to 80 million years ago, Machairoceratops and Diabloceratops may be among the oldest ceratopsids yet found.

Diabloceratops skull
A restoration of a Diabloceratops skull. When it was first described in 2010, it was the oldest known ceratopsid, and first centrosaurine found south of Montana. (Photo by Perry Quan)
[Read about the recent discovery of the very oldest (so far): “Dinosaur Fossil From Utah May Be Oldest Ceratopsid Ever Found“]

Lund and his colleagues point out that the two types of dinos both lived in the southern reaches of what was once a mini-continent, known as Laramidia, that comprised much of the intermountain West.

The fact that dinosaurs with similarly-shaped, spiked frills have been found in the south of this region, but not the north, suggests that there may have been some evolutionary pressures at work — sexual or otherwise — that made them preferred among southern dinos but not among northern. [See what one northern ceratops looked like: “New Species of Horned Dinosaur With Flashy, Butterfly-Shaped Frill Discovered in Montana“]

In the end, the discovery of Machairoceratops may add more to the natural history record than just a fearsome face and creepy name.

Writing in PLOS One, the team notes, “Considered together, the .. evidence distinguishes Machairoceratops from all other centrosaurine dinosaurs, and increases the known ceratopsian diversity in the southern portion of Laramidia.”


ResearchBlogging.orgLund, E., O’Connor, P., Loewen, M., & Jinnah, Z. (2016). A New Centrosaurine Ceratopsid, Machairoceratops cronusi gen et sp. nov., from the Upper Sand Member of the Wahweap Formation (Middle Campanian), Southern Utah PLOS ONE, 11 (5) DOI: 10.1371/journal.pone.0154403

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  1. urbain

    Another unknown creature.

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