A recent study conducted by the Florida Museum of Natural History reveals that this apex predator is a type of Cebucid crocodile with origins in South America.
The Cebushid crocodile ruled the South American landscape after the dinosaurs vanished, remaining dominant until roughly 11 million years ago. Image credit: Jorge Mackey.
The sebecids were the last survivors of notosuchia, a large and varied group of extinct crocodiles with fossil records that trace back to the era of dinosaurs.
Notosuchians exhibited a wide range of sizes, diets, and habitats, distinguishing themselves from their alligator relatives, as most inhabited terrestrial environments.
The Sevecid behaved like a carnivorous dinosaur, sprinting with four long, agile limbs and tearing flesh with its notorious teeth.
Some species were equipped with protective armor made of bone plates embedded in the skin, reaching lengths of up to 6 m (20 feet).
The catastrophic mass extinction at the end of the Cretaceous period, which eradicated non-avian dinosaurs, also nearly led to the extinction of the notosuchians.
In South America, only the Sevecids survived post-dinosaurs, quickly ascending to the role of apex predators.
The open waters separating the Caribbean islands from the South American mainland posed significant challenges for the Sevensids when it came to swimming.
In a new research effort, paleontologist Jonathan Bloch and his colleagues from the Florida Museum of Natural History analyzed vertebrae from fossilized teeth and spinal vertebrae dating back six million years, collected from the Paleopoultry 1 site in Savanna Grande de Boya, Dominican Republic.
“Our first question upon discovering these teeth in the Dominican Republic and other Caribbean islands was: what could they be?” Dr. Bloch mentioned.
The team also examined 18 million-year-old teeth found in Cuba and 29 million-year-old specimens from Puerto Rico.
“The fossils suggested evidence supporting the Girllandia hypothesis,” they noted.
This theory posits that a temporary land bridge or chain of islands enabled the migration from South America to the Caribbean.
“If the serrated teeth found in other Caribbean islands also belong to the Sevecid, the history of these giant reptiles stretches beyond just the Dominican Republic.”
“They would have played a significant role in shaping the ecosystems of this region for millions of years. However, today, evidence of large terrestrial predators is scarce.”
“In their absence, smaller endemic predators like birds, snakes, and crocodiles have evolved to fill gaps in the food chain,” he added.
“We could not have predicted this just by studying modern ecosystems,” Dr. Bloch remarked.
“The presence of large predators greatly differs from our previous assumptions, and it’s thrilling to explore what further discoveries might await in the Caribbean fossil record.”
The team’s paper was published in Proceedings of the Royal Society B.
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Lázaro W. Viñola López et al. 2025. The South American Sevecid from the Miocene of Hispaniola documents the presence of apex predators in the ecosystems of the Early West Indies. Proc. R. Soc. B 292 (2045): 20242891; doi: 10.1098/rspb.2024.2891
Source: www.sci.news
