A team led by University of Chicago paleontologist Paul Sereno has described a new species of spinosaur from the central Sahara, a fish-eating giant called Spinosaurus mirabilis that sports a scimitar-shaped cranial crest found on no other known dinosaur. The discovery, published in Science on February 19, 2026, represents the first unequivocal new Spinosaurus species identified in more than a century, and rewrites what scientists thought they knew about how these predators evolved and displayed to one another in the wetlands of Cretaceous Africa.
A Scimitar Crest With No Known Parallel
The defining feature of Spinosaurus mirabilis is a tall, curved cranial crest shaped like a scimitar blade, a structure that has no close match among the roughly 1,300 named dinosaur species. The peer-reviewed paper in Science describes the crest in detail and uses quantitative morphometric comparisons, including principal component analysis, to show how sharply it diverges from every other spinosaurid skull on record. That statistical rigor matters because spinosaur fossils are notoriously fragmentary, and past species diagnoses have sometimes rested on ambiguous scraps. Here the team argues that the crest alone, combined with other cranial features, is diagnostic enough to erect a new species with confidence.
What was the crest for? The Natural History Museum interprets the structure as likely serving a display function, perhaps for attracting mates or intimidating rivals. That reading fits the cover illustration for the same issue of Science, which depicts two S. mirabilis individuals sparring over a coelacanth carcass on a forested riverbank approximately 95 million years ago. If the crest was indeed a visual signal, it would join the sail on the animal’s back as a second dramatic display structure, making Spinosaurus mirabilis one of the most ornamented large predators known from the Mesozoic.
Saharan Desert Was a Lush Riverbank System
The fossils come from the Farak Formation at a locality called Jenguebi in Niger, deep in what is now the inland Sahara. Approximately 95 million years ago, during the Cenomanian stage of the Late Cretaceous, this region looked nothing like the sand sea it is today. The Natural History Museum describes the area as a wetland and riparian system threaded with rivers and bordered by forests, an environment rich in fish and other aquatic prey. That ecological context helps explain why a large, fish-eating predator could thrive so far from any modern coastline.
The discovery also builds on a broader body of work about how spinosaurs lived in and around water. A 2020 study published in Nature examined the tail of Spinosaurus aegyptiacus and used physical experiments and computational models to argue that the animal was capable of strong aquatic propulsion. The new find from Niger does not directly test swimming ability, but it places a second, clearly distinct Spinosaurus species in an inland river system, reinforcing the idea that these animals were ecologically tied to freshwater habitats rather than open marine environments. Sereno’s team has informally called S. mirabilis a “hell heron,” a label that captures the image of a long-snouted wading predator ambushing fish from the shallows.
First New Spinosaurus Species in Over a Century
The original Spinosaurus aegyptiacus was named by German paleontologist Ernst Stromer in 1915 from fossils found in Egypt, and those bones were destroyed during a World War II bombing raid on Munich. For more than 100 years, every spinosaur discovery either belonged to a different genus entirely or was assigned, sometimes tentatively, to that single Egyptian species. The University of Chicago announcement calls S. mirabilis the first unequivocal new Spinosaurus species in more than a century, a claim that rests on the team’s morphometric evidence distinguishing it from S. aegyptiacus at the species level rather than lumping it into an existing taxon.
That century-long gap is partly a product of where spinosaurs lived and how their bones preserve. Saharan fieldwork is logistically punishing, and the porous, lightly built skulls of spinosaurids tend to fall apart before burial. The University of Chicago team describes a multi-season field campaign at Jenguebi followed by painstaking reconstruction, including the creation of a replica skull and crest and a full visualization and animation pipeline to bring the animal back to life digitally. Plans are already in place for a museum exhibit featuring the reconstructed material, which would give the public its first look at a Spinosaurus species described from scratch rather than patched together from Stromer’s lost notes.
Why the Crest Challenges Standard Spinosaur Thinking
Most public attention on spinosaurs over the past decade has focused on locomotion: did they swim, wade, or hunt from shore? The 2020 tail study, which tested how a tall, flexible tail performed in water, has often been cited as evidence that these predators were more aquatic than other large theropods. Spinosaurus mirabilis shifts the conversation in a different direction by showing that spinosaurs were also diversifying above the waterline, evolving elaborate head ornamentation that would have been most visible on land or at the surface. If the scimitar crest was brightly colored or supported soft tissues, as Sereno and colleagues suggest in their formal description, it could have played a central role in social behavior even while the animal remained specialized for a semi-aquatic lifestyle.
The crest also forces a rethink of how constrained spinosaur skulls really were. For years, paleontologists have emphasized the functional demands of fish-eating: long, narrow snouts with conical teeth and pressure-sensitive pits, all tuned for snapping up slippery prey. Within that framework, there did not seem to be much evolutionary room for extravagant ornamentation. By documenting a crest that rises high above the rest of the skull and curves forward like a blade, the authors argue that display structures could evolve without compromising feeding performance. In their view, S. mirabilis demonstrates that even highly specialized predators can explore surprising morphological extremes when social or sexual selection provides a strong enough push.
A New Window Into Cretaceous River Predators
Spinosaurus mirabilis also adds nuance to the broader picture of Cretaceous ecosystems in northern Africa. Fossils from the Farak Formation show that these river systems supported a mix of giant fish, crocodile-like reptiles, and other dinosaurs, creating a food web in which a large, fish-focused predator could carve out a niche. By placing a distinct Spinosaurus species in this inland setting, the Science authors strengthen the case that spinosaurs were not coastal oddities confined to deltas and shorelines but key players in continental freshwater habitats. The Harvard coverage of earlier tail research highlighted how unusual it was to find a giant theropod so adapted to water; S. mirabilis suggests that such adaptations may have been part of a broader radiation rather than a single evolutionary experiment.
At the same time, the new species underscores how much remains unknown. The Jenguebi material is more complete than many spinosaur finds, but it still represents only a fraction of the skeleton, and no associated soft tissues are preserved. Questions about exact body proportions, growth stages, and potential differences between males and females remain open. The authors of the Cenomanian study emphasize that future field seasons in Niger may yet uncover additional individuals, including juveniles, that could reveal whether the crest changed through life or varied among adults. For now, the scimitar crest stands as a striking reminder that even among well-known dinosaur groups, entirely new body plans can still emerge from the rocks of the Sahara.
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*This article was researched with the help of AI, with human editors creating the final content.
