Researchers have identified a new genus of extinct long-snouted crocodile, Herugavialis cairensis, from 45-million-year-old fossils found in Egypt’s Mokattam Formation. The study, published October 7, 2026, in Royal Society Open Science, used CT scans to reclassify a specimen discovered in 1927 that was previously misidentified for nearly a century.
The fossil, which includes a nearly complete skull, was recovered from the same limestone formation used by ancient Egyptians to carve the Great Sphinx. For decades, scientists categorized the animal as part of the Tomistoma genus, the group containing the living false gharial, because of its long snout and similar skull shape. However, an international team from Egypt, Germany, Sweden, and the U.K. recently applied modern anatomical and evolutionary analysis to the specimen, which is currently housed in the Stuttgart State Museum of Natural History in Germany.
Herugavialis: The “Sphinx Crocodile”
The researchers gave the new genus the name Herugavialis, while the species is designated cairensis, a direct reference to Cairo. The naming was inspired by a physical coincidence: like the Great Sphinx, the fossil is missing the tip of its nose.
Technical analysis revealed that the snout length represents roughly 64 percent of the total skull length. These proportions, along with specific characteristics in the eye socket and other cranial regions, distinguish it from the false gharial. The study concludes that Herugavialis represents an early branch of the gavialoid group, specialized fish-hunters that once inhabited warm, shallow seas in northern Egypt during the Middle Eocene epoch.
CT Scans Extract New Data from Historical Skull
The discovery did not require new field excavations but instead relied on CT scans and digital reconstruction to examine the internal structure of the skull. This approach allowed researchers to ask new questions of a 99-year-old specimen.
The center's initiative aims to use modern imaging and analysis to extract new data from these historical collections.
Climate Shifts Drove Mediterranean Crocodile Diversity
The presence of Herugavialis provides a window into the Mediterranean’s prehistoric diversity. However, this diversity declined during the late Eocene and Oligocene, a shift likely caused by falling global temperatures and receding sea levels.
This pattern reversed during the Miocene epoch as temperatures and sea levels rose again. Paul Burke stated that crocodiles eventually vanished from the Mediterranean about 6 million years ago when the sea largely dried up. Today, the Nile crocodile is the only species remaining in Egypt, where laws prohibit the killing or trading of the animals, though poaching persists.
Global Crocodilian Conservation Status
While Herugavialis is long extinct, its living relatives face severe modern threats. The gharial and false gharial are currently listed as critically endangered and endangered, respectively. However, the IUCN’s Crocodile Specialist Group (CSG) reports that overall crocodilian conservation has seen significant progress since the group’s formation in 1971.
| Species/Group | Status/Detail |
|---|---|
| Gharial (Gavialis gangeticus) | Critically Endangered; survives in India and Nepal |
| False Gharial (Tomistoma schlegelii) | Endangered; found in Southeast Asia |
| American Alligator | Recovered to nearly 5 million in the southeastern U.S. |
| Global Crocodilians | Over half are now listed as “least concern” |