A newly discovered genus and species of lambeosaurid hadrosaurid dinosaur, Plesiolophus warnerensis, has been identified in southern Alberta, Canada, with origins dating back to the Campanian period of the Cretaceous, approximately 77 million years ago.

Hollow-crowned hadrosauroid dinosaurs, part of the Lambeosaurinae clade, were widely distributed across the Northern Hemisphere toward the end of the Cretaceous, according to Carleton University paleontologist Bradley McPheeters in a recent study published in the Canadian Geoscience Journal.

“The Lambeosaurinae likely originated in Asia, where early diverging members were present during the early Santonian period (86 to 84 million years ago).”

“More derived lambeosaurinae appeared in western North America (Laramidia) by the Early Middle Campanian (84 to 78 million years ago), reaching peak diversity during the Late Campanian (up to 72 million years ago).”

The new species, Plesiolophus warnerensis, was identified from the roof and braincase of a fossilized skull discovered by fossil hunter Wendy Sloboda near the Milk River Ridge Reservoir in southern Alberta.

This significant fossil was excavated from the Oldman Formation, which surprisingly yields little diagnostic material from the region’s diverse duck-billed dinosaurs.

“Plesiolophus warnerensis represents the first diagnostic specimen of an adult lambeosaur from this formation,” the researchers noted in their paper.

Unlike later members, Plesiolophus warnerensis possesses some ancestral characteristics while also exhibiting features similar to those of Parasaurolophus, the clade that ultimately gave rise to iconic hadrosaurid dinosaurs.

To situate the new species within the evolutionary framework, researchers employed phylogenetic analysis, comparing it to 87 other dinosaur species.

The analysis consistently indicates that this species is one of the earliest members of the North American parasaurolophine lineage.

“Although Plesiolophus warnerensis is diagnosed by a unique combination of features, it lacks strong autapomorphies and cannot currently be excluded as a potential ancestor of Parasaurolophus, which occurs in the upper Dinosaur Park formation,” the scientists explained.

“In several respects, this new taxon’s morphology aligns with expectations for a representative of the stratigraphically lower parasaurolophines. Its close morphological resemblance to lambeosaurids signals its temporal proximity to the evolutionary divergence from that clade, while its similarities to immature examples of parasaurolophines suggest a heterochronic process that may have led to the exaggerated crest characteristic of this group.”

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Bradley D. McPheeters et al. A new species of parasaurolophine dinosaur (Hadrosauridae: Lambeosaurinae) discovered from the Oldman Formation in southern Alberta. Canadian Geoscience Journal, published online on July 13, 2026. doi: 10.1139/cjes-2026-0013