Two tiny new horned dinosaur species have been identified from museum specimens unearthed years ago in Alberta, Canada, a new study says.

The 75-million-year-old Unescoceratops koppelhusae—its fossils found in 1995 in Dinosaur Provincial Park—measured about 3 feet (1 meter) long and sported a short frill behind its head, a parrot-like beak, and a hatchet-shaped jaw.

The other new dinosaur species, Gryphoceratops morrisoni, emerged from a scrap of bones collected by paleontologists in the 1950s. Recently a new team "pulled out a little box that's no bigger than a coffee cup and poured [the pieces] on the table," said study leader Michael Ryan, curator of vertebrate paleontology at the Cleveland Museum of Natural History in Ohio.

After fitting the pieces together, they realized "Yup, That's a horned-dino jaw," Ryan said.

"I said, It's different than anything else we've ever seen before—I'm sure we can give that a new name," he said.

Adult Gryphoceratops were no bigger than 1.6 feet (0.5 meter) long, making the species the smallest horned dinosaur found so far in North America, according to the study.

Small Dinosaurs a Rare Find

Both new dinosaur species, which lived during the Cretaceous period, are considered quite old as dinosaur fossils go, Ryan noted—and unusually little for preserved bones of their age.

Small dinosaurs are "a very important part of the understory of the environment, but their bodies are too small" to be naturally preserved, said Ryan, whose study was published online January 24 in the journal Cretaceous Research.

With their small sizes, the newfound dinosaurs "would have been good munchies for someone else," Ryan said. The creatures themselves would've likely eaten tiny amphibians and reptiles. (See pictures of other "extreme" dinosaurs.)

In the new dinosaurs' time, now arid southern Alberta was much more humid, due to its proximity to North America's large, long-gone inland sea, Ryan added.