MEANING: Loki horned face
PERIOD: Late Cretaceous
CONTINENT: North America
Lokiceratops is a ceratopsian dinosaur from the Late Cretaceous period of what is now North America. It was a quadrupedal herbivore, like all ceratopsids, with a beak at the tip of its snout and batteries of teeth for processing vegetation. One of the largest centrosaurines, Lokiceratops grew to around 7 m in length and weighed about 5 t. It lacked a nose horn, but sported a pair of horns above the eyes and an ornately embellished frill. This frill was asymmetrical, and featured enlarged curved, bladelike ossifications.
Abstract from paper: The Late Cretaceous of western North America supported diverse dinosaur assemblages, though understanding patterns of dinosaur diversity, evolution, and extinction has been historically limited by unequal geographic and temporal sampling. In particular, the existence and extent of faunal endemism along the eastern coastal plain of Laramidia continues to generate debate, and finer scale regional patterns remain elusive. Here, we report a new centrosaurine ceratopsid, Lokiceratops rangiformis, from the lower portion of the McClelland Ferry Member of the Judith River Formation in the Kennedy Coulee region along the Canada-USA border. Dinosaurs from the same small geographic region, and from nearby, stratigraphically equivalent horizons of the lower Oldman Formation in Canada, reveal unprecedented ceratopsid richness, with four sympatric centrosaurine taxa and one chasmosaurine taxon. Phylogenetic results show that Lokiceratops, together with Albertaceratops and Medusaceratops, was part of a clade restricted to a small portion of northern Laramidia approximately 78 million years ago. This group, Albertaceratopsini, was one of multiple centrosaurine clades to undergo geographically restricted radiations, with Nasutuceratopsini restricted to the south and Centrosaurini and Pachyrostra restricted to the north. High regional endemism in centrosaurs is associated with, and may have been driven by, high speciation rates and diversity, with competition between dinosaurs limiting their geographic range. High speciation rates may in turn have been driven in part by sexual selection or latitudinally uneven climatic and floral gradients. The high endemism seen in centrosaurines and other dinosaurs implies that dinosaur diversity is underestimated and contrasts with the large geographic ranges seen in most extant mammalian megafauna.
Lokoiceratops is from the Cretaceous. The Cretaceous is a geological period that lasted from about 145 to 66 million years ago. It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin creta, "chalk", which is abundant in the latter half of the period.
The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct flora and fauna, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth by the end of the Cretaceous, coincident with the decline and extinction of previously widespread gymnosperm groups.
The Cretaceous (along with the Mesozoic) ended with the Cretaceous–Paleogene extinction event, a large mass extinction in which many groups, including non-avian dinosaurs, pterosaurs, and large marine reptiles, died out. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary (K–Pg boundary), a geologic signature associated with the mass extinction that lies between the Mesozoic and Cenozoic Eras.
Lokiceratops is a ceratopsian. Ceratopsia is a group of herbivorous, beaked dinosaurs that thrived in what are now North America, Europe, and Asia. They primarily flourished during the Cretaceous Period, although ancestral forms lived earlier, in the Late Jurassic. Ceratopsians lived until the Cretaceous–Paleogene extinction event, 66 million years ago, when they went extinct along with the other non-avian dinosaurs.
Early members of the ceratopsian group were small bipedal animals. Later members became very large quadrupeds and developed elaborate facial horns and frills extending over the neck. While these frills might have served to protect the vulnerable neck from predators, they may also have been used for display or thermoregulation. Ceratopsians ranged in size from 1 meter and 23 kilograms to over 9 meters and 9,100 kilograms.
Ceratopsians are easily recognized by features of the skull. Though less pronounced in basal ceratopsians, more derived species, like the ceratopsids are characterized by beaks, rows of shearing teeth in the back of the jaw, elaborate nasal horns, and a shelf that extends back and up into a frill. Various shapes and arrangements of well-developed brow horns and elaborate spines on the frill are also characteristic of many species.