New ‘scimitar-crested’ Spinosaurus species discovered in the central Sahara

The first indisputable evidence of a new species of Spinosaurus in over a century belongs to S. mirabilis, named for its scimitar-shaped crest and found at a locality far from the ocean’s edge

2026-02-19

(Press-News.org) A new paper published in Science describes the discovery of Spinosaurus mirabilis, a new spinosaurid species found in Niger. A 20-person team led by Paul Sereno, PhD, Professor of Organismal Biology and Anatomy at the University of Chicago, unearthed the find at a remote locale in the central Sahara, adding important new fossil finds to the closing chapter of spinosaurid evolution.

Eye-catching anatomy

The scimitar-shaped crest of S. mirabilis was so large and unexpected that the paleontologists initially didn’t recognize it for what it was when they plucked it and some jaw fragments from the desert surface in November 2019. Returning with a larger team in 2022 and finding two additional crests, they realized the novelty of the new species they had unearthed. Based on the crest’s surface texture and interior vascular canals, the experts believe the crest was sheathed in keratin. They reckon that this display feature was brightly colored in life, curving toward the sky as a blade-shaped beacon.

Another striking feature of the skull is its interdigitating upper and lower tooth rows, which make a deadly trap for slippery fish. Interdigitating teeth, where those of the lower jaw protrude outward and between those of the uppers, is a time-honored adaptation among fish-eaters in the fossil record — including aquatic ichthyosaurs, semi-aquatic crocodile and airborne pterosaurs. Among dinosaurs, it sets Spinosaurus and closest kin apart.

“This find was so sudden and amazing, it was really emotional for our team,” Sereno said. “I’ll forever cherish the moment in camp when we crowded around a laptop to look at the new species for the first time, after one member of our team generated 3D digital models of the bones we found to assemble the skull — on solar power in the middle of the Sahara. That’s when the significance of the discovery really registered.”

Far from shore

Previously, spinosaurid bones and teeth had only been found principally in coastal deposits not far from the shoreline, leading some experts to hypothesize recently that these fish-eating theropods may have been fully aquatic, pursuing prey underwater.

However, the new fossil area in Niger documents animals that were living inland, some 500-1000 km from the nearest marine shoreline. Their proximity to intact partial skeletons of long-necked dinosaurs, all buried in river sediments, suggest they lived in a forested inland habitat dissected by rivers.

“I envision this dinosaur as a kind of ‘hell heron’ that had no problem wading on its sturdy legs into two meters of water but probably spent most of its time stalking shallower traps for the many large fish of the day,” Sereno said.

A remarkable expedition to Niger

The journey that culminated in this remarkable discovery started with a single sentence in a monograph from the 1950s, where a French geologist mentioned finding a single sabre-shaped fossilized tooth resembling those of the giant predator Carcharodontosaurus found in Egypt’s Western Desert at the turn of the last century.

“No one had been back to that tooth site in over 70 years,” Sereno mused. “It was an adventure and a half wandering into the sand seas to search for this locale and then find an even more remote fossil area with the new species. Now all of the young scholars who joined me are co-authors on the report gracing the cover of Science.”

The team ended up meeting a local Tuareg man who led them on his motorbike deep into the center of the Sahara, where he had seen huge fossil bones. After nearly a full day of travel with no shortage of doubts regarding the success of the effort, he led them to a fossil field. There, with little time to spare before returning to camp, the team found teeth and jaw bones of the new species of Spinosaurus.

“I was attracted to the Sahara like a magnet once I set foot there 30 years ago,” Sereno said. “There’s nowhere else like it. It’s as beautiful as it is daunting.” After excavating more than 100 tons of fossil finds, he says of the Sahara, “If you can brave the elements and are willing to go after the unknown, you might just uncover a lost world.”

This latest discovery adds to Niger’s rich legacy in paleontology and archaeology, both of which Sereno has engaged. He has led an international award-winning effort to build the world’s first zero-energy museum, the Museum of the River, on an island in the center of Niger’s capital city of Niamey. It will showcase their world class patrimony that documents Africa’s lost world of dinosaurs, now including an astonishing spinosaur species, as well as stone-age cultures that once lived in a Green Sahara.

“The local people we work with are my lifelong friends, now including the man who led us to Jenguebi and the astonishing spinosaur. They understand the importance of what we’re doing together — for science and for their country,” Sereno said.

Envisioning Spinosaurus mirabilis with multimedia science and paleoart

Back home in Chicago, Sereno’s team at his South Side Fossil Lab in Washington Park cleaned and then CT scanned the teeth and bones, assembling a digital skull rendering for the research report. Using that rendering, Sereno worked with paleoartist Dani Navarro in Madrid to create an action scene involving flesh reconstructions of the new species tussling over a coelacanth carcass. Navarro went farther, creating a detailed 3D physical model of S. mirabilis by adding flesh over a skeletal reconstruction.

Other paleoartists in Chicago (Jonathan Metzger) and Italy (Davide la Torre) animated Nararro’s model, bringing back to life the action behind the scene chosen for the cover of Science. More adept programs, cameras and drones have revolutionized visualization in paleontology as practiced today in the field and lab.

Inspiring young minds

As part of these reconstruction efforts, the team also prepared a replica of the newly discovered skull and a touchable, colorful model of the scimitar crest.

On March 1, in the wake of the Science paper, both replicas will join Sereno’s previous Dinosaur Expedition exhibit at the Chicago Children’s Museum, where kids will be among the first to get up close and personal with this latest dinosaur find.

“Letting kids feel the excitement of new discoveries — that’s key to ensuring the next generation of scientists who will discover many more things about our precious planet worth preserving,” Sereno said.

“New scimitar-crested Spinosaurus species from the Sahara caps stepwise spinosaurid radiation” was published in Science in February 2026. Co-authors are Paul C. Sereno, Daniel Vidal, Nathan P. Myhrvold, Evan Johnson-Ransom, María Ciudad Real, Stephanie L. Baumgart, Noelia Sánchez Fontela, Todd L. Green, Evan T. Saitta, Boubé Adamou, Lauren L. Bop, Tyler M. Keillor, Erin C. Fitzgerald, Didier B. Dutheil, Robert A. S. Laroche, Alexandre V. Demers-Potvin, Álvaro Simarro, Francesc Gascó-Lluna, Ana Lázaro, Arturo Gamonal, Charles V. Beightol, Vincent Reneleau, Rachel Vautrin, Filippo Bertozzo, Alejandro Granados, Grace Kinney-Broderick, Jordan C. Mallon, Rafael M. Lindoso and Jahandar Ramezani.

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