Not all new dinosaur species are discovered in the field. Many are discovered by examination of museum collections. In 2014, paleontologist Nick Longrich identified two previously unknown horned dinosaurs from Alberta, Canada based on fossils collected in the 1920s and ‘30s.
The two dinosaurs, Pentaceratops and Kosmoceratops, had so far only been known from New Mexico and Utah, respectively. The specimens placed in Pentaceratops represent a new species, P. aquilonius, while the specimen placed in Kosmoceratops is too fragmentary to determine if it belongs to the original species K. richardsoni, or if it represents a new species.
Although the specimens are incomplete, they show important details which allowed Longrich to determine that they were unlike other dinosaurs known from Alberta. The Kosmoceratops specimen was discovered in 1928 near the Red Deer River in what is now Dinosaur Provincial Park in southern Alberta. The Pentaceratops specimens were discovered in 1937 at the Manyberries locality in southeastern Alberta. All the specimens are found in rocks dating to about 75 million years ago, and are currently housed in the Canadian Museum of Nature in Ottawa.