Two new species of beaked and frilled dinosaur were identified earlier this month by paleontologists who re-examined fossil remains discovered in Canada years ago.
The Cretaceous period animals, which have named Unescoceratops koppelhusae and Gryphoceratops morrisoni, lived between 75 million and 83 million years ago.
Both animals were relatively small. Unescoceratops was between one and two meters long, weighing no more than about 91 kilograms, while Gryphoceratops was, according to researchers, unlikely to have been longer than about one-half meter. An adult Gryphoceratops would have weighed less than an adult Unescoceratops.
The dinosaurs’ diminutive size makes their fossilized remains a somewhat unusual paleontological artifact.
“Small-bodied dinosaurs are typically poorly represented in the fossil record, which is why fragmentary remains like these new leptoceratopsids can make a big contribution to our understanding of dinosaur ecology and evolution,” Dr. David C. Evans of the Royal Ontario Museum, one of the authors of a study documenting the discovery, said.
Neither animal had large horns or extensive frills, such as those sported by more famous contemporary dinosaurs such as Triceratops horribilis, though both had relatively small frill-like structures atop their skulls.
They did, however, have some unusual skull features.
Unescoceratops had bone projecting from below the jaw, giving it a facial feature that may have somewhat resembled a chin, while Gryphoceratops had a jaw that was both shorter and deeper than any other animal within the same family of dinosaurs.
The family to which Unescoceratops and Gryphoceratops belonged was the leptoceratopsians, which is a taxon within the clade of dinosaurs known as ceratopsians.
Leptoceratopsians were native to land that is known today as Asia and North America.
The fossil that allowed identification of Unescoceratops, a lower left jaw fragment, was found in Alberta’s Dinosaur Provincial Park in 1995. Researchers identified it as a fossilized remnant of an animal called Leptoceratops gracilis, but further study by paleontologists Michael Ryan of the Cleveland Museum of Natural History and Evans led to a conclusion that it is an example of a previously unknown animal.
The genus name Unescoceratops honors the designation of the area in which remains of the animal was found as a United Nations World Heritage Site. The species name honors the wife of the scientist who found the fossil of the animal in 1995.
The Gryphoceratops remains were originally found in 1950, also in Alberta. Its species name honors the man who found that fossil, Levi Sternberg.
A study that announces the discovery of the two new Leptoceratopsians appears in the Jan. 24, 2012 issue of Cretaceous Research.