A horned dinosaur discovered by an Alberta junior high school science teacher in 1972 has been officially named a new species, researchers said Wednesday.

University of Alberta paleontologists said the fossil specimens found in a bonebed along Pipestone Creek near Grande Prairie by Al Lakusta, now retired, were known to be similar to those found in southwestern Alberta in the 1940s. That dinosaur also belonged to the genus Pachyrhinosaurus, which translates to "thick-nosed lizard."

But it took a detailed examination to determine that the bones were from a distinct species.

The new dinosaur species will be known as Pachyrhinosaurus lakustai to honour its discoverer, according to Philip Currie, Canada Research chair of dinosaur paleobiology from the University of Alberta. The discovery was announced at a ceremony in Grande Prairie on Wednesday.

Lakusta made the discovery at a time when northwestern Alberta was not known for its dinosaur bones, Currie said in announcing the dinosaur's name. As a result, Lakusta, 66, an amateur fossil collector, did the excavating and storing of the bones himself until the Royal Tyrrell Museum began an official excavation in 1986.

The site is notable because of the density of bones discovered: Researchers at University of Alberta said the bonebed contains up to 100 bones per square metre, with 3,500 bones — including 14 skulls — having been removed from the site so far.

The researchers said the density, placement and state of the bones suggests a Pachyrhinosaurus herd may have died during the attempted crossing of a river during a flood about 72.5 million years ago, during the late Cretaceous period.

Their carcasses then washed downriver where they were torn apart by carnivores, the researcher said.

"The density of the Pipestone Creek bonebed is exceptional and surpasses many of Alberta's other ... bonebed sites," Currie said in a statement.

"The preservation of the material is outstanding and was easy to collect. The number of bones, from all age groups, made complex investigations possible regarding behaviour and growth patterns."