Paleontologists have identified a new Early Miocene species of the rhinocerotid genus Epiaceratherium from the fossilized remains found in the Canadian High Arctic.
Life restoration of Epiaceratherium itjilik, at its forested lake habitat, Devon Island; the plants and animals shown are based on fossil finds at the site, including the transitional seal species Puijila darwini. Image credit: Julius Csotonyi.
The new rhino species lived in what is now Canada about 23 million years ago (Early Miocene epoch).
Named Epiaceratherium itjilik, it is most closely related to other rhino species that thrived in Europe millions of years earlier.
“Today there are only five species of rhinos in Africa and Asia, but in the past they were found in Europe and North America, with more than 50 species known from the fossil record,” said Dr. Danielle Fraser, a researcher at the Canadian Museum of Nature, Carleton University and the Smithsonian National Museum of Natural History.
“The addition of this Arctic species to the rhino family tree now offers new insights to our understanding of their evolutionary history.”
Epiaceratherium itjilik was relatively small and slight, similar in size to the modern Indian rhinoceros, but lacking a horn.
The animal’s fossilized remains were recovered from the fossil-rich lake deposits in Haughton Crater on Devon Island, Nunavut.
“What’s remarkable about the Arctic rhino is that the fossil bones are in excellent condition,” said Dr. Marisa Gilbert, also from the Canadian Museum of Nature.
“They are three dimensionally preserved and have only been partially replaced by minerals.”
“About 75% of the skeleton was discovered, which is incredibly complete for a fossil.”
The authors placed Epiaceratherium itjilik in the rhino family tree by studying the occurrence of 57 other species of rhinocerotids, almost all extinct.
The results came from visiting museum collections, combing through the scientific literature and using databases.
The researchers were also able to place each rhinocerotid geographically in one of five continental regions.
It was an exhaustive process — each species was scored based on where they were found, using a mathematical modeling approach to determine rates of dispersal among those different continents within the family, Rhinocerotidae.
The team’s analysis offers new insights into how rhinos dispersed over millions of years between North America and Europe (via Greenland), using the North Atlantic Land Bridge.
Previous studies suggested this land bridge may have only have functioned as a dispersal corridor until around 56 million years ago.
But the new analysis with Epiaceratherium itjilik and its related species suggests that dispersals occurred from Europe to North America much more recently, potentially as late as the Miocene.
“It’s always exciting and informative to describe a new species,” Dr. Fraser said.
“But there is more that comes from the identification of Epiaceratherium itjilik, as our reconstructions of rhino evolution show that the North Atlantic played a much more important role in their evolution than previously thought.”
“More broadly, this study reinforces that the Arctic continues to offer up new knowledge and discoveries that expand on our understanding of mammal diversification over time.”
The results appear in the journal Nature Ecology & Evolution.
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D. Fraser et al. Mid-Cenozoic rhinocerotid dispersal via the North Atlantic. Nat Ecol Evol, published online October 28, 2025; doi: 10.1038/s41559-025-02872-8
