A newly identified fossil species, Wadisuchus kassabi, dating to the Campanian period (about 80 million years ago), extends the evolutionary history of Dyrosauridae and underscores Egypt’s Western Desert as an important center for early marine crocodile evolution.
In Egypt’s Western Desert, where layers of red sandstone and green shale emerge from the dry plains of Kharga Oasis, paleontologists have discovered a fossil that changes how scientists view crocodile evolution.
The finding, published in The Zoological Journal of the Linnean Society, was made by a team of Egyptian paleontologists who identified a new species named Wadisuchus kassabi. This crocodile lived approximately 80 million years ago and now represents the earliest known member of the Dyrosauridae, an ancient family of crocodiles distinct from modern species.
Dyrosaurids inhabited coastal and marine environments rather than freshwater ones. They possessed long, narrow snouts and fine, pointed teeth suited for catching slippery prey such as fish and turtles. Their persistence and spread following the mass extinction that wiped out the dinosaurs provide key insights into how reptiles survived and evolved as global ecosystems transformed.
Naming the species and honoring Egyptian legacy
The name Wadisuchus kassabi reflects both Egypt’s geography and cultural heritage. “Wadi” (“وادي,” Arabic for “valley”) refers to the New Valley region where the fossil was found, while “Suchus” references the crocodile god Sobek. The species name also pays tribute to Professor Ahmed Kassab of Assiut University, whose contributions to Egyptian paleontology have inspired future generations of researchers.
3D digital model of the Wadisuchus composite skull (MUVP 180, MUVP 635, MUVP 636, MUVP 637), generated using CT scanning and 3D surface reconstruction. Credit: Produced by Belal Salem and Joseph Georanke, with data courtesy of Mansoura University Vertebrate Paleontology Center (MUVP).
Fossil discoveries and anatomical insights
Professor Hesham Sallam, Egyptian Vertebrate Paleontologist at Mansoura University, and senior author of the study, said: “The fossils of Wadisuchus kassabi were excavated near Kharga and Baris oases in Egypt’s Western Desert. They include two partial skulls and two snout tips representing four individuals at different stages of growth, providing rare insight into how dyrosaurids developed.”
Sallam added: “High-resolution CT scans and 3D surface models enabled us to reveal unprecedented anatomical details.”
Sara Saber, Assistant Lecturer at Assiut University, member of the Sallam Lab team at MUVP, and lead author of the study, said: “Wadisuchus kassabi, was a 3.5–4-meter-long (11.5-13 feet) crocodile-like reptile with a very long snout and tall, sharp teeth. It differed from other dyrosaurids, in having four teeth at the front of the snout instead of the primitive five, nostrils positioned on top of the snout for surface breathing, and a deep notch at the tip of the snout where the jaws met. These features show a gradual adaptation in the dyrosaurid bite, marking an important step in their evolutionary history.”
Saber added: “Beyond the distinctive features of Wadisuchus, it plays a crucial role in understanding the origin of the dyrosaurid group. The new species pushes back evidence for an African origin of Dyrosauridae and suggests that their diversification began earlier than previously thought—possibly during the Early Coniacian–Santonian (about 87–83 million years ago), rather than the traditionally assumed Maastrichtian (about 72–66 million years ago).”
Africa’s role as the cradle of Dyrosauridae
Belal Salem, PhD student at Ohio University, member of the Sallam Lab, Curator of Fossil Reptiles and Birds at MUVP, and faculty member at Benha University, states: “This discovery indicates that Africa was the cradle of dyrosaurid evolution, from which later lineages spread across the globe and our phylogenetic analyses consistently place Wadisuchus as an ancestor of the dyrosaurid group.”
Salem continued: “The significance of Wadisuchus lies not only in what it reveals about the evolutionary history of this remarkable group of crocodiles—though that is a major achievement—but also in what it reminds us of: Egypt’s Western Desert still holds treasures that preserve the secrets of our planet’s deep past. Our mission is not only to uncover these fossils but also to protect the fossil-rich sites from urban expansion and agricultural encroachment. They are a legacy for generations of Egyptians to come.”
Reference: “An early dyrosaurid (Wadisuchus kassabi gen. et sp. nov.) from the Campanian of Egypt sheds light on the origin and biogeography of Dyrosauridae” by Sara Saber, Belal S Salem, Khaled Ouda, Abdullah S Gohar, Sanaa El-Sayed, Patrick M O’Connor and Hesham M Sallam, 27 October 2025, Zoological Journal of the Linnean Society.
DOI: 10.1093/zoolinnean/zlaf134
Funding: Mansoura University, Science and Technology Development Fund, National Geographic Society
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