New York: Researchers have identified a new species of fossil dog that roamed the coast of eastern North America approximately 12 million years ago. This coyote-sized dog - named Cynarctus wangi -- was a member of the extinct subfamily Borophaginae, commonly known as bone-crushing dogs because of their powerful jaws and broad teeth, the researchers said. "In this respect they are believed to have behaved in a similar way to hyenas today," said the study's lead author, Steven Jasinski, doctoral student at the University of Pennsylvania in the US. Fossils from terrestrial species from this region and time period are relatively rare, thus the find helps paleontologists fill in important missing pieces about what prehistoric life was like on North American's East Coast. "Most fossils known from this time period represent marine animals, who become fossilized more easily than animals on land," Jasinski said. "It is quite rare we find fossils from land animals in this region during this time, but each one provides important information for what life was like then," Jasinski noted. The study was published in the Journal of Paleontology. When the researchers first began their investigation of the specimen, which had been found by an amateur collector along the beach under the Choptank Formation in Maryland's Calvert Cliffs region, they presumed it was a known species of borophagine dog. But when they compared features of the occlusal surfaces, where the top and bottom teeth meet, of the previously known and the new specimens, they found notable differences. They concluded that the specimen represented a distinct species new to science. Despite its strong jaws, the researchers believe C. wangi wouldn't have been wholly reliant on meat to sustain itself. "Based on its teeth, probably only about a third of its diet would have been meat," Jasinski said. "It would have supplemented that by eating plants or insects, living more like a mini-bear than like a dog," Jasinski pointed out.