During the Triassic period, about 205 million years ago, a relative of modern hunted on land rather than in water — new research shows. Fossils indicate the animal hunted on land like a fox or a jackal and had a skull built for powerful bites.
A new genus and species
The specimen was found back in 1948 at Ghost Ranch in New Mexico — a well-known dinosaur bonebed. At the time, researchers tentatively assigned it to Hesperosuchus agilis, an early, small relative of crocodiles and alligators. But new research shows the specimen has an unusually short snout and a reinforced, thick skull that set it apart enough to warrant its own genus and species.
The authors gave the animal the scientific name Eosphorosuchus lacrimosa. The fossils come from Late Triassic deposits (about 237–201 million years ago). What survives today are a skull, the bones of a single hind leg, one vertebra, and three scales; the animal’s size can be compared to a large dog.
A detailed comparison with another H. agilis specimen found roughly 15 feet (about 5 m) from the new find showed clear differences between the two specimens. In Eosphorosuchus the snout is much shorter, the postorbital bone in the temporal region of the skull is more triangular, and the lower jaw has matching features that likely served to anchor powerful jaw muscles. Taken together, these traits indicate a very strong bite.
“This is the first truly convincing evidence that two crocodile-like creatures with different functional morphologies coexisted,” said Miranda Margulis-Onuma, a study coauthor and a paleontologist at Yale University.
How they shared the landscape
Because E. lacrimosa and H. agilis lived side by side and died in the same geological layer — probably from the same event, possibly a flood — scientists suggest they occupied different ecological niches. For example, short-snouted crocodile relatives might have hunted larger, less agile prey, while long-snouted species were adapted to a different feeding strategy.
The paleontologist pointed out that the early stages of crocodylomorph evolution are still poorly understood: the fossil record contains few specimens, and many Triassic species are known from only a single example. Each newly described specimen changes our picture of that time.
“We have very little data on early crocodiles, so every new fossil changes the picture,” Margulis-Onuma said. “If we continue to describe the material we already have, and perhaps find new specimens, the story will keep changing.”
Based on Live Science
