Crocodile Fossils Could Help Explain Life 96 Million Years Ago

Crocodile Fossils

A new species of crocodile-relative from the Age of Dinosaurs, Scolomastax sahlsteini, has been discovered at a fossil excavation site in Texas, according to a study published in The Anatomical Record and coauthored by a University of Tennessee, Knoxville, paleontologist.

The newly discovered fossil can provide insight into the ecosystem of North America in the mid-Cretaceous period and what life was like for organisms living 96 million years ago.

“People sometimes think that crocs haven’t changed much since the age of dinosaurs, but that just isn’t true,” said Stephanie Drumheller-Horton, a paleontologist at the University of Tennessee and coauthor of the study. “This little croc has several weird features that make us think it ate hard prey items and maybe even plants. We don’t have anything like it alive in the world today.”

“S. sahlsteini is part of a group of early croc relatives called paralligatorids,” said Alan Turner, coauthor and associate professor of anatomical sciences at Stony Brook University.

“Most members of this group are from Asia, but we are starting to have a few examples of them from Texas,” he said. “This helps us understand how groups were dispersing between Asia and North America prior to the closing of the Western Interior Seaway, the inland sea that split North America in two.”

The species was found in the Arlington Archosaur Site (AAS), a fossil-rich site discovered in 2003 in Arlington, Texas, by a group of amateur paleontologists that included dinosaur enthusiast Arthur Sahlstein. Sahlstein volunteered as caretaker of the site and has helped uncover numerous fossils, including the jaw from S. sahlsteini. The newly found species is named in his honor.

“The AAS wouldn’t be the success it is if it weren’t for the small army of dedicated volunteers donating their time, energy, expertise, and resources,” said Chris Noto, lead author of the study and associate professor of biological sciences at the University of Wisconsin–Parkside. “It is only fitting that we honor one of our most valuable and prolific members.”

Work at the Arlington site is supported in part by the National Geographic Society, which provided a grant to complete fieldwork at the site, and the Perot Museum of Nature and Science in Dallas, which curates the fossils found at the site and organizes volunteers. Currently, excavations at AAS are on hiatus as the research team works on describing the thousands of specimens that have been discovered.

“The site has not ceased to give up its secrets,” said Sahlstein.